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Archive for the ‘Immunotherapy’ Category

New studies link cell cycle proteins to immunosurveillance of premalignant cells

Curator: Stephen J. Williams, Ph.D.

The following is from a Perspectives article in the journal Science by Virinder Reen and Jesus Gil called “Clearing Stressed Cells: Cell cycle arrest produces a p21-dependent secretome that initaites immunosurveillance of premalignant cells”. This is a synopsis of the Sturmlechener et al. research article in the same issue (2).

Complex organisms repair stress-induced damage to limit the replication of faulty cells that could drive cancer. When repair is not possible, tissue homeostasis is maintained by the activation of stress response programs such as apoptosis, which eliminates the cells, or senescence, which arrests them (1). Cellular senescence causes the arrest of damaged cells through the induction of cyclin-dependent kinase inhibitors (CDKIs) such as p16 and p21 (2). Senescent cells also produce a bioactive secretome (the senescence-associated secretory phenotype, SASP) that places cells under immunosurveillance, which is key to avoiding the detrimental inflammatory effects caused by lingering senescent cells on surrounding tissues. On page 577 of this issue, Sturmlechner et al. (3) report that induction of p21 not only contributes to the arrest of senescent cells, but is also an early signal that primes stressed cells for immunosurveillance.Senescence is a complex program that is tightly regulated at the epigenetic and transcriptional levels. For example, exit from the cell cycle is controlled by the induction of p16 and p21, which inhibit phosphorylation of the retinoblastoma protein (RB), a transcriptional regulator and tumor suppressor. Hypophosphorylated RB represses transcription of E2F target genes, which are necessary for cell cycle progression. Conversely, production of the SASP is regulated by a complex program that involves super-enhancer (SE) remodeling and activation of transcriptional regulators such as nuclear factor κB (NF-κB) or CCAAT enhancer binding protein–β (C/EBPβ) (4).

Senescence is a complex program that is tightly regulated at the epigenetic and transcriptional levels. For example, exit from the cell cycle is controlled by the induction of p16 and p21, which inhibit phosphorylation of the retinoblastoma protein (RB), a transcriptional regulator and tumor suppressor. Hypophosphorylated RB represses transcription of E2F target genes, which are necessary for cell cycle progression. Conversely, production of the SASP is regulated by a complex program that involves super-enhancer (SE) remodeling and activation of transcriptional regulators such as nuclear factor κB (NF-κB) or CCAAT enhancer binding protein–β (C/EBPβ) (4).

Sturmlechner et al. found that activation of p21 following stress rapidly halted cell cycle progression and triggered an internal biological timer (of ∼4 days in hepatocytes), allowing time to repair and resolve damage (see the figure). In parallel, C-X-C motif chemokine 14 (CXCL14), a component of the PASP, attracted macrophages to surround and closely surveil these damaged cells. Stressed cells that recovered and normalized p21 expression suspended PASP production and circumvented immunosurveillance. However, if the p21-induced stress was unmanageable, the repair timer expired, and the immune cells transitioned from surveillance to clearance mode. Adjacent macrophages mounted a cytotoxic T lymphocyte response that destroyed damaged cells. Notably, the overexpression of p21 alone was sufficient to orchestrate immune killing of stressed cells, without the need of a senescence phenotype. Overexpression of other CDKIs, such as p16 and p27, did not trigger immunosurveillance, likely because they do not induce CXCL14 expression.In the context of cancer, senescent cell clearance was first observed following reactivation of the tumor suppressor p53 in liver cancer cells. Restoring p53 signaling induced senescence and triggered the elimination of senescent cells by the innate immune system, prompting tumor regression (5). Subsequent work has revealed that the SASP alerts the immune system to target preneoplastic senescent cells. Hepatocytes expressing the oncogenic mutant NRASG12V (Gly12→Val) become senescent and secrete chemokines and cytokines that trigger CD4+ T cell–mediated clearance (6). Despite the relevance for tumor suppression, relatively little is known about how immunosurveillance of oncogene-induced senescent cells is initiated and controlled.

Source of image: Reen, V. and Gil, J. Clearing Stressed Cells. Science Perspectives 2021;Vol 374(6567) p 534-535.

References

2. Sturmlechner I, Zhang C, Sine CC, van Deursen EJ, Jeganathan KB, Hamada N, Grasic J, Friedman D, Stutchman JT, Can I, Hamada M, Lim DY, Lee JH, Ordog T, Laberge RM, Shapiro V, Baker DJ, Li H, van Deursen JM. p21 produces a bioactive secretome that places stressed cells under immunosurveillance. Science. 2021 Oct 29;374(6567):eabb3420. doi: 10.1126/science.abb3420. Epub 2021 Oct 29. PMID: 34709885.

More Articles on Cancer, Senescence and the Immune System in this Open Access Online Scientific Journal Include

Bispecific and Trispecific Engagers: NK-T Cells and Cancer Therapy

Natural Killer Cell Response: Treatment of Cancer

Issues Need to be Resolved With ImmunoModulatory Therapies: NK cells, mAbs, and adoptive T cells

New insights in cancer, cancer immunogenesis and circulating cancer cells

Insight on Cell Senescence

Immune System Stimulants: Articles of Note @pharmaceuticalintelligence.com

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Yet another Success Story: Machine Learning to predict immunotherapy response

Curator and Reporter: Dr. Premalata Pati, Ph.D., Postdoc

Immune-checkpoint blockers (ICBs) immunotherapy appears promising for various cancer types, offering a durable therapeutic advantage. Only a number of cases with cancer respond to this therapy. Biomarkers are required to adequately predict the responses of patients. This article evaluates this issue utilizing a system method to characterize the immune response of the anti-tumor based on the entire tumor environment. Researchers build mechanical biomarkers and cancer-specific response models using interpretable machine learning that predict the response of patients to ICB.

The lymphatic and immunological systems help the body defend itself by combating. The immune system functions as the body’s own personal police force, hunting down and eliminating pathogenic baddies.

According to Federica Eduati, Department of Biomedical Engineering at TU/e, “The immune system of the body is quite adept at detecting abnormally behaving cells. Cells that potentially grow into tumors or cancer in the future are included in this category. Once identified, the immune system attacks and destroys the cells.”

Immunotherapy and machine learning are combining to assist the immune system solve one of its most vexing problems: detecting hidden tumorous cells in the human body.

It is the fundamental responsibility of our immune system to identify and remove alien invaders like bacteria or viruses, but also to identify risks within the body, such as cancer. However, cancer cells have sophisticated ways of escaping death by shutting off immune cells. Immunotherapy can reverse the process, but not for all patients and types of cancer. To unravel the mystery, Eindhoven University of Technology researchers used machine learning. They developed a model to predict whether immunotherapy will be effective for a patient using a simple trick. Even better, the model outperforms conventional clinical approaches.

The outcomes of this research are published on 30th June, 2021 in the journal Patterns in an article entitled “Interpretable systems biomarkers predict response to immune-checkpoint inhibitors”.

The Study

  • Characterization of the tumor microenvironment from RNAseq and prior knowledge
  • Multi-task machine-learning models for predicting antitumor immune responses
  • Identification of cancer-type-specific, interpretable biomarkers of immune responses
  • EaSIeR is a tool to predict biomarker-based immunotherapy response from RNA-seq

“Tumor also contains multiple types of immune and fibroblast cells which can play a role in favor of or anti-tumor, and communicates among themselves,” said Oscar Lapuente-Santana, a researcher doctoral student in the computational biology group. “We had to learn how complicated regulatory mechanisms in the micro-environment of the tumor affect the ICB response. We have used RNA sequencing datasets to depict numerous components of the Tumor Microenvironment (TME) in a high-level illustration.”

Using computational algorithms and datasets from previous clinical patient care, the researchers investigated the TME.

Eduati explained

While RNA-sequencing databases are publically available, information on which patients responded to ICB therapy is only available for a limited group of patients and cancer types. So, to tackle the data problem, we used a trick.

All 100 models learned in the randomized cross-validation were included in the EaSIeR tool. For each validation dataset, we used the corresponding cancer-type-specific model: SKCM for the melanoma Gide, Auslander, Riaz, and Liu cohorts; STAD for the gastric cancer Kim cohort; BLCA for the bladder cancer Mariathasan cohort; and GBM for the glioblastoma Cloughesy cohort. To make predictions for each job, the average of the 100 cancer-type-specific models was employed. The predictions of each dataset’s cancer-type-specific models were also compared to models generated for the remaining 17 cancer types.

From the same datasets, the researchers selected several surrogate immunological responses to be used as a measure of ICB effectiveness.

Lapuente-Santana stated

One of the most difficult aspects of our job was properly training the machine learning models. We were able to fix this by looking at alternative immune responses during the training process.

Some of the researchers employed the machine learning approach given in the paper to participate in the “Anti-PD1 Response Prediction DREAM Challenge.”

DREAM is an organization that carries out crowd-based tasks with biomedical algorithms. “We were the first to compete in one of the sub-challenges under the name cSysImmunoOnco team,” Eduati remarks.

The researchers noted,

We applied machine learning to seek for connections between the obtained system-based attributes and the immune response, estimated using 14 predictors (proxies) derived from previous publications. We treated these proxies as individual tasks to be predicted by our machine learning models, and we employed multi-task learning algorithms to jointly learn all tasks.

The researchers discovered that their machine learning model surpasses biomarkers that are already utilized in clinical settings to evaluate ICB therapies.

But why are Eduati, Lapuente-Santana, and their colleagues using mathematical models to tackle a medical treatment problem? Is this going to take the place of the doctor?

Eduati explains

Mathematical models can provide an overview of the interconnection between individual molecules and cells and at the same time predicting a particular patient’s tumor behavior. This implies that immunotherapy with ICB can be personalized in a patient’s clinical setting. The models can aid physicians with their decisions about optimum therapy, it is vital to note that they will not replace them.

Furthermore, the model aids in determining which biological mechanisms are relevant for the biological response.

The researchers noted

Another advantage of our concept is that it does not need a dataset with known patient responses to immunotherapy for model training.

Further testing is required before these findings may be implemented in clinical settings.

Main Source:

Lapuente-Santana, Ó., van Genderen, M., Hilbers, P. A., Finotello, F., & Eduati, F. (2021). Interpretable systems biomarkers predict response to immune-checkpoint inhibitorsPatterns, 100293. https://www.cell.com/patterns/pdfExtended/S2666-3899(21)00126-4

Other Related Articles published in this Open Access Online Scientific Journal include the following:

Inhibitory CD161 receptor recognized as a potential immunotherapy target in glioma-infiltrating T cells by single-cell analysis

Reporter: Dr. Premalata Pati, Ph.D., Postdoc

https://pharmaceuticalintelligence.com/2021/02/20/inhibitory-cd161-receptor-identified-in-glioma-infiltrating-t-cells-by-single-cell-analysis-2/

Immunotherapy may help in glioblastoma survival

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

https://pharmaceuticalintelligence.com/2019/03/16/immunotherapy-may-help-in-glioblastoma-survival/

Deep Learning for In-silico Drug Discovery and Drug Repurposing: Artificial Intelligence to search for molecules boosting response rates in Cancer Immunotherapy: Insilico Medicine @John Hopkins University

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2016/07/17/deep-learning-for-in-silico-drug-discovery-and-drug-repurposing-artificial-intelligence-to-search-for-molecules-boosting-response-rates-in-cancer-immunotherapy-insilico-medicine-john-hopkins-univer/

Machine Learning (ML) in cancer prognosis prediction helps the researcher to identify multiple known as well as candidate cancer diver genes

Curator and Reporter: Dr. Premalata Pati, Ph.D., Postdoc

https://pharmaceuticalintelligence.com/2021/05/04/machine-learning-ml-in-cancer-prognosis-prediction-helps-the-researcher-to-identify-multiple-known-as-well-as-candidate-cancer-diver-genes/

AI System Used to Detect Lung Cancer

Reporter: Irina Robu, PhD

https://pharmaceuticalintelligence.com/2019/06/28/ai-system-used-to-detect-lung-cancer/

Cancer detection and therapeutics

Curator: Larry H. Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2016/05/02/cancer-detection-and-therapeutics/

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Inhibitory CD161 receptor recognized as a potential immunotherapy target in glioma-infiltrating T cells by single-cell analysis

Reporter: Dr. Premalata Pati, Ph.D., Postdoc

 

Brain tumors, especially the diffused Gliomas are of the most devastating forms of cancer and have so-far been resistant to immunotherapy. It is comprehended that T cells can penetrate the glioma cells, but it still remains unknown why infiltrating cells miscarry to mount a resistant reaction or stop the tumor development.

Gliomas are brain tumors that begin from neuroglial begetter cells. The conventional therapeutic methods including, surgery, chemotherapy, and radiotherapy, have accomplished restricted changes inside glioma patients. Immunotherapy, a compliance in cancer treatment, has introduced a promising strategy with the capacity to penetrate the blood-brain barrier. This has been recognized since the spearheading revelation of lymphatics within the central nervous system. Glioma is not generally carcinogenic. As observed in a number of cases, the tumor cells viably reproduce and assault the adjoining tissues, by and large, gliomas are malignant in nature and tend to metastasize. There are four grades in glioma, and each grade has distinctive cell features and different treatment strategies. Glioblastoma is a grade IV glioma, which is the crucial aggravated form. This infers that all glioblastomas are gliomas, however, not all gliomas are glioblastomas.

Decades of investigations on infiltrating gliomas still take off vital questions with respect to the etiology, cellular lineage, and function of various cell types inside glial malignancies. In spite of the available treatment options such as surgical resection, radiotherapy, and chemotherapy, the average survival rate for high-grade glioma patients remains 1–3 years (1).

A recent in vitro study performed by the researchers of Dana-Farber Cancer Institute, Massachusetts General Hospital, and the Broad Institute of MIT and Harvard, USA, has recognized that CD161 is identified as a potential new target for immunotherapy of malignant brain tumors. The scientific team depicted their work in the Cell Journal, in a paper entitled, “Inhibitory CD161 receptor recognized in glioma-infiltrating T cells by single-cell analysis.” on 15th February 2021.

To further expand their research and findings, Dr. Kai Wucherpfennig, MD, PhD, Chief of the Center for Cancer Immunotherapy, at Dana-Farber stated that their research is additionally important in a number of other major human cancer types such as 

  • melanoma,
  • lung,
  • colon, and
  • liver cancer.

Dr. Wucherpfennig has praised the other authors of the report Mario Suva, MD, PhD, of Massachusetts Common Clinic; Aviv Regev, PhD, of the Klarman Cell Observatory at Broad Institute of MIT and Harvard, and David Reardon, MD, clinical executive of the Center for Neuro-Oncology at Dana-Farber.

Hence, this new study elaborates the effectiveness of the potential effectors of anti-tumor immunity in subsets of T cells that co-express cytotoxic programs and several natural killer (NK) cell genes.

The Study-

IMAGE SOURCE: Experimental Strategy (Mathewson et al., 2021)

 

The group utilized single-cell RNA sequencing (RNA-seq) to mull over gene expression and the clonal picture of tumor-infiltrating T cells. It involved the participation of 31 patients suffering from diffused gliomas and glioblastoma. Their work illustrated that the ligand molecule CLEC2D activates CD161, which is an immune cell surface receptor that restrains the development of cancer combating activity of immune T cells and tumor cells in the brain. The study reveals that the activation of CD161 weakens the T cell response against tumor cells.

Based on the study, the facts suggest that the analysis of clonally expanded tumor-infiltrating T cells further identifies the NK gene KLRB1 that codes for CD161 as a candidate inhibitory receptor. This was followed by the use of 

  • CRISPR/Cas9 gene-editing technology to inactivate the KLRB1 gene in T cells and showed that CD161 inhibits the tumor cell-killing function of T cells. Accordingly,
  • genetic inactivation of KLRB1 or
  • antibody-mediated CD161 blockade

enhances T cell-mediated killing of glioma cells in vitro and their anti-tumor function in vivo. KLRB1 and its associated transcriptional program are also expressed by substantial T cell populations in other forms of human cancers. The work provides an atlas of T cells in gliomas and highlights CD161 and other NK cell receptors as immune checkpoint targets.

Further, it has been identified that many cancer patients are being treated with immunotherapy drugs that disable their “immune checkpoints” and their molecular brakes are exploited by the cancer cells to suppress the body’s defensive response induced by T cells against tumors. Disabling these checkpoints lead the immune system to attack the cancer cells. One of the most frequently targeted checkpoints is PD-1. However, recent trials of drugs that target PD-1 in glioblastomas have failed to benefit the patients.

In the current study, the researchers found that fewer T cells from gliomas contained PD-1 than CD161. As a result, they said, “CD161 may represent an attractive target, as it is a cell surface molecule expressed by both CD8 and CD4 T cell subsets [the two types of T cells engaged in response against tumor cells] and a larger fraction of T cells express CD161 than the PD-1 protein.”

However, potential side effects of antibody-mediated blockade of the CLEC2D-CD161 pathway remain unknown and will need to be examined in a non-human primate model. The group hopes to use this finding in their future work by

utilizing their outline by expression of KLRB1 gene in tumor-infiltrating T cells in diffuse gliomas to make a remarkable contribution in therapeutics related to immunosuppression in brain tumors along with four other common human cancers ( Viz. melanoma, non-small cell lung cancer (NSCLC), hepatocellular carcinoma, and colorectal cancer) and how this may be manipulated for prevalent survival of the patients.

References

(1) Anders I. Persson, QiWen Fan, Joanna J. Phillips, William A. Weiss, 39 – Glioma, Editor(s): Sid Gilman, Neurobiology of Disease, Academic Press, 2007, Pages 433-444, ISBN 9780120885923, https://doi.org/10.1016/B978-012088592-3/50041-4.

Main Source

Mathewson ND, Ashenberg O, Tirosh I, Gritsch S, Perez EM, Marx S, et al. 2021. Inhibitory CD161 receptor identified in glioma-infiltrating T cells by single-cell analysis. Cell.https://www.cell.com/cell/fulltext/S0092-8674(21)00065-9?elqTrackId=c3dd8ff1d51f4aea87edd0153b4f2dc7

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19th Annual Koch Institute Summer Symposium on Cancer Immunotherapy, June 12, 2020 at MIT’s Kresge Auditorium

 

Other related articles published in this Open Access Online Scientific Journal include the following:

 

Single Cell Sequencing:

Part 4.1 in Genomics Volume 2

Latest in Genomics Methodologies for Therapeutics: Gene Editing, NGS & BioInformatics, Simulations and the Genome Ontology 

On Amazon.com since 12/28/2019

https://www.amazon.com/dp/B08385KF87

 

4.1.3   Single-cell Genomics: Directions in Computational and Systems Biology – Contributions of Prof. Aviv Regev @Broad Institute of MIT and Harvard, Cochair, the Human Cell Atlas Organizing Committee with Sarah Teichmann of the Wellcome Trust Sanger Institute

Curator: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2018/09/03/single-cell-genomics-directions-in-computational-and-systems-biology-contributions-of-ms-aviv-regev-phd-broad-institute-of-mit-and-harvard-cochair-the-human-cell-atlas-organizing-committee-wit/

 

4.1.4   Cellular Genetics

https://www.sanger.ac.uk/science/programmes/cellular-genetics

 

4.1.5   Cellular Genomics

https://www.garvan.org.au/research/cellular-genomics

 

4.1.6   SINGLE CELL GENOMICS 2019 – sometimes the sum of the parts is greater than the whole, September 24-26, 2019, Djurönäset, Stockholm, Sweden http://www.weizmann.ac.il/conferences/SCG2019/single-cell-genomics-2019

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2019/05/29/single-cell-genomics-2019-september-24-26-2019-djuronaset-stockholm-sweden/

 

4.1.7   Norwich Single-Cell Symposium 2019, Earlham Institute, single-cell genomics technologies and their application in microbial, plant, animal and human health and disease, October 16-17, 2019, 10AM-5PM

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2019/06/04/norwich-single-cell-symposium-2019-earlham-institute-single-cell-genomics-technologies-and-their-application-in-microbial-plant-animal-and-human-health-and-disease-october-16-17-2019-10am-5pm/

 

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https://pharmaceuticalintelligence.com/2019/05/23/newly-found-functions-of-b-cell/

 

4.1.9 RESEARCH HIGHLIGHTS: HUMAN CELL ATLAS

https://www.broadinstitute.org/research-highlights-human-cell-atlas

 

CRISPR – 200 articles in the Journal

 

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Immunotherapy may help in glioblastoma survival

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

https://pharmaceuticalintelligence.com/2019/03/16/immunotherapy-may-help-in-glioblastoma-survival/

 

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CAR T-CELL THERAPY MARKET: 2020 – 2027

G L O B A L  M A R K E T  A N A L Y S I S  A N D

I N D U S T R Y  F O R E C A S T

 

DISCLAIMER

LPBI Group’s decision to publish the Table of Contents of this Report does not imply endorsement of the Report

Aviva Lev-Ari, PhD, RN, Founder 1.0 & 2.0 LPBI Group

Guest Reporter: MIKE WOOD

Marketing Executive
BIOTECH FORECASTS

 

ABOUT BIOTECH FORECASTS

BIOTECH FORECASTS is a full-service market research and business- consulting firm primarily focusing on healthcare, pharmaceutical, and biotechnology industries. BIOTECH FORECASTS provides global as well as medium and small Pharmaceutical and Biotechnology businesses with unmatched quality of “Market Research Reports” and “Business Intelligence Solutions”. BIOTECH FORECASTS has a targeted view to provide business insights and consulting to assist its clients to make strategic business decisions, and achieve sustainable growth in their respective market domain.

UPDATED on 10/13/2020

CAR T-CELL THERAPY MARKET

Mike Wood

Mike Wood

Marketing Executive at Biotech Forecasts

CAR T-cell therapy as a part of adoptive cell therapy (ACT), has become one of the most rapidly growing and promising fields in the Immuno-oncology. As compared to the conventional cancer therapies, CAR T-cell therapy is the single-dose solution for the treatment of various cancers, significantly for some lethal forms of hematological malignancies.

CAR T-cell therapy mainly involves the use of engineered T-cells, the process starts with the extraction of T-cells through leukapheresis, either from the patient (autologous) or a healthy donor (allogeneic). After the expression of a synthetic receptor (Chimeric Antigen Receptor) in the lab, the altered T-cells are expanded to the right dose and administered into the patient’s body. where they target and attach to a specific antigen on the tumor surface, to kill the cancerous cells by igniting the apoptosis.

The global CAR T-cell therapy market was valued at $734 million in 2019 and is estimated to reach $4,078 million by 2027, registering a CAGR of 23.91% from 2020 to 2027.

Factors that drive the market growth involve, (1) Increased in funding for R&D activities pertaining to cell and gene therapy. By H1 2020 cell and gene therapy companies set new records in the fundraising despite the pandemic crisis. For Instance, by June 2020 totaled $1,452 Million raised in Five IPOs including, Legend Biotech ($487M), Passage Bio ($284M), Akouos ($244M), Generation Bio ($230M), and Beam Therapeutics ($207M), which is 2.5 times the total IPO of 2019.

Moreover, in 2019 cell therapy companies specifically have raised $560 million of venture capital, including Century Therapeutics ($250M), Achilles Therapeutics Ltd. ($121M in series B), NKarta Therapeutics Inc. ($114M), and Tmunity Therapeutics ($75M in Series B).

(2) Increased in No. of Approved Products, By July 2020, there are a total of 03 approved CAR T-cell therapy products, including KYMRIAH®, YESCARTA®, and the most recently approved TECARTUS™ (formerly KTE-X19). Furthermore, two CAR T-cell therapies BB2121, and JCAR017 are expected to get the market approval by the end of 2020 or in early 2021.

Other factors that boost the market growth involves; (3) increase in government support, (4) ethical acceptance of Cell and Gene therapy for cancer treatment, (5) rise in the prevalence of cancer, and (6) an increase in awareness regarding the CAR T-cell therapy.

However, high costs associated with the treatment (KYMRIAH® cost around $475,000, and YESCARTA® costs $373,000 per infusion), long production hours, obstacles in treating solid tumors, and unwanted immune responses & potential side effects might hamper the market growth.

The report also presents a detailed quantitative analysis of the current market trends and future estimations from 2020 to 2027.

The forecasts cover 2 Approach Types, 5 Antigen Types, 5 Application Types, Regions, and 14 Countries.

The report comes with an associated file covering quantitative data from all numeric forecasts presented in the report, as well as with a Clinical Trials Data File.

KEY FINDINGS

The report has the following key findings:

  • The global CAR T-cell therapy market accounted for $734 million in 2019 and is estimated to reach $4,078 million by 2027, registering a CAGR of 23.91% from 2020 to 2027.
  • By approach type the autologous segment was valued at $655.26 million in 2019 and is estimated to reach $ 3,324.52 million by 2027, registering a CAGR of 22.51% from 2020 to 2027.
  • By approach type, the allogeneic segment exhibits the highest CAGR of 32.63%.
  • Based on the Antigen segment CD19 was the largest contributor among the other segments in 2019.
  • The Acute lymphocytic leukemia (ALL) segment generated the highest revenue and is expected to continue its dominance in the future, followed by the Diffuse large B-cell lymphoma (DLBCL) segment.
  • North America dominated the global CAR T-cell therapy market in 2019 and is projected to continue its dominance in the future.
  • China is expected to grow the highest in the Asia-Pacific region during the forecast period.

TOPICS COVERED

The report covers the following topics:

  • Market Drivers, Restraints, and Opportunities
  • Porters Five Forces Analysis
  • CAR T-Cell Structure, Generations, Manufacturing, and Pricing Models
  • Top Winning Strategies, Top Investment Pockets
  • Analysis of by Approach Type, Antigen Type, Application, and Region
  • 51 Company Profiles, Product Portfolio, and Key Strategies
  • Approved Products Profiles, and list of Expected Approvals
  • COVID-19 Impact on the Cell and Gene Therapy Industry
  • CAR T-cell therapy clinical trials analysis from 1997 to 2019
  • Market analysis and forecasts from 2020 to 2027

FORECAST SEGMENTATION

By Approach Type

  • Autologous
  • Allogeneic

By Antigen Type

  • CD19
  • CD20
  • BCMA
  • MSLN
  • Others

By Application

  • Acute lymphoblastic leukemia (ALL)
  • Diffuse large B-Cell lymphoma (DLBCL)
  • Multiple Myeloma (MM)
  • Acute Myeloid Leukemia (AML)
  • Other Cancer Indications

By Region

  • North America: USA, Canada, Mexico
  • Europe: UK, Germany, France, Spain, Italy, Rest of Europe
  • Asia-Pacific: China, Japan, India, South Korea, Rest of Asia-Pacific
  • LAMEA: Brazil, South Africa, Rest of LAMEA

Contact at info@biotechforecasts.com for any Queries or Free Report Sample

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The global CAR T-cell therapy market was valued at $734 million in 2019 and is estimated to reach $4,078 million by 2027, registering a CAGR of 23.91% from 2020 to 2027. hashtagcelltherapy hashtaggenetherapy hashtagimmunotherapy hashtagcancertreatment hashtagcartcell hashtagregenerativemedicine hashtagbiotech hashtagcancer

 

Table of Contents

 

CHAPTER 1: INTRODUCTION

1.1 REPORT DESCRIPTION 17
1.2 TOPICS COVERED 19
1.3 KEY MARKET SEGMENTS 20
1.4 KEY BENEFITS 21
1.5 RESEARCH METHODOLOGY 21
1.6 TARGET AUDIENCE 22
1.7 COMPANIES MENTIONED 23

CHAPTER 2: EXECUTIVE SUMMARY

2.1 EXECUTIVE SUMMARY 26
2.2 CXO PROSPECTIVE 29

CHAPTER 3: MARKET OVERVIEW

3.1 MARKET DEFINITION AND SCOPE 30
3.2 KEY FINDINGS 31
3.3 TOP INVESTMENT POCKETS 32
3.4 TOP WINNING STRATEGIES 33
3.4.1.Top winning strategies, by year, 2017-2019* 34
3.4.2.Top winning strategies, by development, 2017-2019*(%) 34
3.4.3.Top winning strategies, by company, 2017-2019* 35
3.5 TOP PLAYER POSITIONING, BY PIPELINE VOLUME, 2019 38
3.6 PORTERS FIVE FORCES ANALYSIS 39
3.7 COVID19 IMPACT ON CELL AND GENE THERAPY (CGT) INDUSTRY 41
3.8 MARKET DYNAMICS 46
3.8.1    Drivers 46
3.8.1.1   Increase in funding for R&D activities of CAR T-cell therapy 46
3.8.1.2   The rise in the prevalence of cancer 47
3.8.1.3   Increase in awareness regarding CAR T-cell therapy 47

 

3.8.2    Restrains 48
3.8.2.1   The high cost of CAR T-cell therapy treatment 48
3.8.2.2   Unwanted immune responses and side effects 48
3.8.2.3   Long production time 48
3.8.2.4   Obstacles in treating solid tumors 49
3.8.3    Opportunities 49
3.8.3.1   Untapped potential for emerging markets 49

CHAPTER 4: CAR T-CELL THERAPY, A BRIEF INTRODUCTION

4.1 OVERVIEW 50
4.2 SIXTY YEARS HISTORY OF CAR T-CELL THERAPY 51
4.3 CAR T-CELL STRUCTURE AND GENERATIONS 53
4.4 CAR T-CELL MANUFACTURING PROCESSES 56
4.5 PRICING AND PAYMENT MODELS FOR CAR T-CELL THERAPIES 59

CHAPTER 5: CAR T-CELL THERAPY MARKET, BY APPROACH TYPE

5.1 OVERVIEW 61
5.1.1    Market size and forecast 62
5.2 AUTOLOGOUS 63
5.2.1    Key market trends 63
5.2.2    Key growth factors and opportunities 64
5.2.3    Market size and forecast 64
5.2.4    Market size and forecast by country 65
5.3 ALLOGENEIC 66
5.3.1    Key market trends 67
5.3.2    Key growth factors and opportunities 68
5.3.3    Market size and forecast 68
5.3.4    Market size and forecast by country 69

CHAPTER 6: CAR T-CELL THERAPY MARKET, BY ANTIGEN TYPE

6.1 OVERVIEW 70
6.1.1         Market size and forecast 71
6.2 CD19 72
6.2.1         Market size and forecast 73
6.2.2         Market size and forecast by country 74

 

6.3 CD20 75
6.3.1 Market size and forecast 76
6.3.2 Market size and forecast by country 77
6.4 BCMA 78
6.4.1 Market size and forecast 79
6.4.2 Market size and forecast by country 80
6.5 MSLN 81
6.5.1 Market size and forecast 82
6.5.2 Market size and forecast by country 83
6.6 OTHERS 84
6.6.1 Market size and forecast 85
6.6.2 Market size and forecast by country 86

CHAPTER 7: CAR T-CELL THERAPY MARKET, BY APPLICATION

7.1 OVERVIEW 87
7.1.1       Market size and forecast 88
7.2 ACUTE LYMPHOBLASTIC LEUKEMIA (ALL) 89
7.2.1       Market size and forecast 90
7.2.2       Market size and forecast by country 91
7.3 DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL) 92
7.3.1       Market size and forecast 93
7.3.2       Market size and forecast by country 94
7.4 MULTIPLE MYELOMA (MM) 95
7.4.1       Market size and forecast 96
7.4.2       Market size and forecast by country 97
7.5 ACUTE MYELOID LEUKEMIA (AML) 98
7.5.1       Market size and forecast 99
7.5.2       Market size and forecast by country 100
7.6 OTHERS 101
7.6.1       Market size and forecast 102
7.6.2       Market size and forecast by country 103

CHAPTER 8: CAR T-CELL THERAPY MARKET, BY REGION

8.1 OVERVIEW 104
8.1.1       Market size and forecast 104
8.2 NORTH AMERICA 105
8.2.1       Key market trends 105
8.2.2       Key growth factors and opportunities 105

 

8.2.3       Market size and forecast, by country 106
8.2.4       Market size and forecast, by approach type 106
8.2.5       Market size and forecast, by antigen type 107
8.2.6 Market size and forecast, by application 107
8.2.6.1 U.S. market size and forecast, by approach type 108
8.2.6.2 U.S. market size and forecast, by antigen type 108
8.2.6.3 U.S. market size and forecast, by application 109
8.2.6.4 Canada market size and forecast, by approach type 110
8.2.6.5 Canada market size and forecast, by antigen type 110
8.2.6.6 Canada market size and forecast, by application 111
8.2.6.7 Mexico market size and forecast, by approach type 112
8.2.6.8 Mexico market size and forecast, by antigen type 112
8.2.6.9 Mexico market size and forecast, by application 113
8.3 EUROPE 114
8.4.1 Key market trends 114
8.4.2 Key growth factors and opportunities 114
8.4.3 Market size and forecast, by country 115
8.4.4 Market size and forecast, by approach type 115
8.4.5 Market size and forecast, by antigen type 116
8.4.6 Market size and forecast, by application 116
8.3.6.1 UK market size and forecast, by approach type 117
8.3.6.2 UK market size and forecast, by antigen type 117
8.3.6.3 UK market size and forecast, by application 118
8.3.6.4 Germany market size and forecast, by approach type 119
8.3.6.5 Germany market size and forecast, by antigen type 119
8.3.6.6 Germany market size and forecast, by application 120
8.3.6.7 France market size and forecast, by approach type 121
8.3.6.8 France market size and forecast, by antigen type 121
8.3.6.9 France market size and forecast, by application 122
8.3.6.10 Spain market size and forecast, by approach type 123
8.3.6.11 Spain market size and forecast, by antigen type 123
8.3.6.12 Spain market size and forecast, by application 124
8.3.6.13 Italy market size and forecast, by approach type 125
8.3.6.14 Italy market size and forecast, by antigen type 125
8.3.6.15 Italy market size and forecast, by application 126
8.3.6.16 Rest of Europe market size and forecast, by approach type 127
8.3.6.17 Rest of Europe market size and forecast, by antigen type 127
8.3.6.18 Rest of Europe market size and forecast, by application 128
8.4 ASIA-PACIFIC 129
8.4.1 Key market trends 129
8.4.2 Key growth factors and opportunities 129
8.4.3 Market size and forecast, by country 130
8.4.4 Market size and forecast, by approach type 130

 

8.4.5       Market size and forecast, by antigen type 131
8.4.6 Market size and forecast, by application 131
8.4.6.1 China market size and forecast, by approach type 132
8.4.6.2 China market size and forecast, by antigen type 132
8.4.6.3 China market size and forecast, by application 133
8.4.6.4 Japan market size and forecast, by approach type 134
8.4.6.5 Japan market size and forecast by antigen type 134
8.4.6.6 Japan market size and forecast, by application 135
8.4.6.7 India market size and forecast, by approach type 136
8.4.6.8 India market size and forecast, by antigen type 136
8.4.6.9 India market size and forecast, by application 137
8.4.6.10 South Korea market size and forecast, by approach type 138
8.4.6.11 South Korea market size and forecast, by antigen type 138
8.4.6.12 South Korea market size and forecast, by application 139
8.4.6.13 Rest of Asia-Pacific market size and forecast, by approach type 140
8.4.6.14 Rest of Asia-Pacific market size and forecast, by antigen type 140
8.4.6.15 Rest of Asia-Pacific market size and forecast, by application 141
8.5 LAMEA 142
8.5.1 Key market trends 142
8.5.2 Key growth factors and opportunities 142
8.5.3 Market size and forecast, by country 143
8.5.4 Market size and forecast, by approach type 143
8.5.5 Market size and forecast, by antigen type 144
8.5.6 Market size and forecast, by application 144
8.5.6.1 Brazil market size and forecast by approach type 145
8.5.6.2 Brazil market size and forecast, by antigen type 145
8.5.6.3 Brazil market size and forecast, by application 146
8.5.6.4 South Africa market size and forecast, by approach type 147
8.5.6.5 South Africa market size and forecast, by antigen type 147
8.5.6.6 South Africa market size and forecast, by application 148
8.5.6.7 Rest of LAMEA market size and forecast by approach type 149
8.5.6.8 Rest of LAMEA market size and forecast, by antigen type 149
8.5.6.9 Rest of LAMEA market size and forecast, by application 150

CHAPTER 9: CLINICAL TRIALS ANALYSIS & PRODUCT PROFILES

9.1 OVERVIEW 151
9.1.1      No. of Clinical Trials from 1997 to 2019 151
9.1.2      Clinical Trials from 1997 to 2019: Based on Approach Type 152
9.1.3      Clinical Trials from 1997 to 2019: Based on Antigen Type 153
9.1.4      Clinical Trials from 1997 to 2019: Based on Application 154
9.1.5      Clinical Trials from 1997 to 2019: Based on Region 155

 

9.2 EXPECTED APPROVALS 156
9.3 APPROVED PRODUCTS PROFILES 157
9.3.1      KYMRIAH® 157
9.3.2      YESCARTA® 159
9.3.3      TECARTUS™ 161

CHAPTER 10: COMPANY PROFILES

10.1       Abbvie Inc. 162
10.2       Adaptimmune Therapeutics Plc 164
10.3 Allogene Therapeutics, Inc. 166
10.4 Amgen, Inc 168
10.5 Anixa Biosciences, Inc. 170
10.6 Arcellx, Inc. 172
10.7 Atara Biotherapeutics, Inc. 173
10.8 Autolus Therapeutics Plc. 175
10.9 Beam Therapeutics, Inc. 177
10.10 Bellicum Pharmaceuticals, Inc. 179
10.11 BioNtech SE 181
10.12 Bluebird Bio, Inc. 183
10.13 Carsgen Therapeutics, Ltd 185
10.14 Cartesian Therapeutics, Inc. 187
10.15 Cartherics Pty Ltd. 188
10.16 Celgene Corporation 189
10.17 Cellectis SA 191
10.18 Cellular Biomedicine Group, Inc. 193
10.19 Celularity, Inc. 195
10.20 Celyad SA 196
10.21 CRISPR Therapeutics AG 198
10.22 Eureka Therapeutics, Inc. 200
10.23 Fate Therapeutics, Inc. 201
10.24 Fortress Biotech, Inc 203
10.25 Gilead Sciences, Inc. 205
10.26 Gracell Biotechnology Ltd 207
10.27 icell Gene Therapeutics 208
10.28 Johnson & Johnson 209
10.29 Juventas Cell Therapy Ltd. 211
10.30 Kuur Therapeutics 212
10.31 Legend Biotech Corp. 213
10.32 Leucid Bio Ltd. 214
10.33 Minerva Biotechnologies Corp. 215

 

10.34     Molecular Medicine SPA (Molmed) 216
10.35     Nanjing Bioheng Biotech Co., Ltd. 218
10.36     Noile-Immune Biotech Inc. 219
10.37     Novartis AG 220
10.38     Oxford Biomedica PLC 222
10.39     Persongen Biotherapeutics (Suzhou) Co., Ltd. 224
10.40     Poseida Therapeutics, Inc. 226
10.41     Precigen, Inc. 227
10.42     Precision Biosciences, Inc. 229
10.43     Sorrento Therapeutics, Inc. 231
10.44     Takara Bio Inc. 233
10.45     Takeda Pharmaceutical Company Ltd. 235
10.46     TC Biopharm Ltd. 237
10.47     Tessa Therapeutics Pte Ltd. 238
10.48     Tmunity Therapeutics, Inc. 239
10.49     Unum Therapeutics Inc. 240
10.50     Xyphos Inc. 242
10.51     Ziopharm Oncology, Inc. 243

CHAPTER 11: CONCLUSION & STRATEGIC RECOMMENTATIONS

11.1     STRATEGIC RECOMMENDATIONS 245
11.2     CONCLUSION 247

 

CONTACT

info@biotechforecasts.com

MIKE WOOD

Marketing Executive

BIOTECH FORECASTS

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Prime Editing as a New CRISPR Tool to Enhance Precision and Versatility

 

Reporter: Stephen J. Williams, PhD

 

CRISPR has become a powerful molecular for the editing of genomes tool in research, drug discovery, and the clinic

(see posts and ebook on this site below)

 

however, as discussed on this site

(see posts below)

there have been many instances of off-target effects where genes, other than the selected target, are edited out.  This ‘off-target’ issue has hampered much of the utility of CRISPR in gene-therapy and CART therapy

see posts

 

However, an article in Science by Jon Cohen explains a Nature paper’s finding of a new tool in the CRISPR arsenal called prime editing, meant to increase CRISPR specificity and precision editing capabilities.

PRIME EDITING PROMISES TO BE A CUT ABOVE CRISPR

By Jon Cohen | Oct 25th, 2019

Prime editing promises to be a cut above CRISPR Jon Cohen CRISPR, an extraordinarily powerful genome-editing tool invented in 2012, can still be clumsy. … Prime editing steers around shortcomings of both techniques by heavily modifying the Cas9 protein and the guide RNA. … ” Prime editing “well may become the way that disease-causing mutations are repaired,” he says.

Science Vol. 366, No. 6464; DOI: 10.1126/science.366.6464.406

The effort, led by Drs. David Liu and Andrew Anzalone at the Broad Institute (Cambridge, MA), relies on the modification of the Cas9 protein and guide RNA, so that there is only a nick in a single strand of the double helix.  The canonical Cas9 cuts both strands of DNA, and so relies on an efficient gap repair activity of the cell.  The second part, a new type of guide RNA called a pegRNA, contains an RNA template for a new DNA sequence to be added at the target location.  This pegRNA-directed synthesis of the new template requires the attachment of a reverse transcriptase enzymes to the Cas9.  So far Liu and his colleagues have tested the technology on over 175 human and rodent cell lines with great success.  In addition, they had also corrected mutations which cause Tay Sachs disease, which previous CRISPR systems could not do.  Liu claims that this technology could correct over 89% of pathogenic variants in human diseases.

A company Prime Medicine has been formed out of this effort.

Source: https://science.sciencemag.org/content/366/6464/406.abstract

 

Read an article on Dr. Liu, prime editing, and the companies that Dr. Liu has initiated including Editas Medicine, Beam Therapeutics, and Prime Medicine at https://www.statnews.com/2019/11/06/questions-david-liu-crispr-prime-editing-answers/

(interview by StatNews  SHARON BEGLEY @sxbegle)

As was announced, prime editing for human therapeutics will be jointly developed by both Prime Medicine and Beam Therapeutics, each focusing on different types of edits and distinct disease targets, which will help avoid redundancy and allow us to cover more disease territory overall. The companies will also share knowledge in prime editing as well as in accompanying technologies, such as delivery and manufacturing.

Reader of StatNews.: Can you please compare the pros and cons of prime editing versus base editing?

The first difference between base editing and prime editing is that base editing has been widely used for the past 3 1/2 years in organisms ranging from bacteria to plants to mice to primates. Addgene tells me that the DNA blueprints for base editors from our laboratory have been distributed more than 7,500 times to more than 1,000 researchers around the world, and more than 100 research papers from many different laboratories have been published using base editors to achieve desired gene edits for a wide variety of applications. While we are very excited about prime editing, it’s brand-new and there has only been one paper published thus far. So there’s much to do before we can know if prime editing will prove to be as general and robust as base editing has proven to be.

We directly compared prime editors and base editors in our study, and found that current base editors can offer higher editing efficiency and fewer indel byproducts than prime editors, while prime editors offer more targeting flexibility and greater editing precision. So when the desired edit is a transition point mutation (C to T, T to C, A to G, or G to A), and the target base is well-positioned for base editing (that is, a PAM sequence exists approximately 15 bases from the target site), then base editing can result in higher editing efficiencies and fewer byproducts. When the target base is not well-positioned for base editing, or when other “bystander” C or A bases are nearby that must not be edited, then prime editing offers major advantages since it does not require a precisely positioned PAM sequence and is a true “search-and-replace” editing capability, with no possibility of unwanted bystander editing at neighboring bases.

Of course, for classes of mutations other than the four types of point mutations that base editors can make, such as insertions, deletions, and the eight other kinds of point mutations, to our knowledge prime editing is currently the only approach that can make these mutations in human cells without requiring double-stranded DNA cuts or separate DNA templates.

Nucleases (such as the zinc-finger nucleases, TALE nucleases, and the original CRISPR-Cas9), base editors, and prime editors each have complementary strengths and weaknesses, just as scissors, pencils, and word processors each have unique and useful roles. All three classes of editing agents already have or will have roles in basic research and in applications such as human therapeutics and agriculture.

Nature Paper on Prime Editing CRISPR

Search-and-replace genome editing without double-strand breaks or donor DNA (6)

 

Andrew V. Anzalone,  Peyton B. Randolph, Jessie R. Davis, Alexander A. Sousa,

Luke W. Koblan, Jonathan M. Levy, Peter J. Chen, Christopher Wilson,

Gregory A. Newby, Aditya Raguram & David R. Liu

 

Nature volume 576, pages149–157(2019)

 

Abstract

Most genetic variants that contribute to disease1 are challenging to correct efficiently and without excess byproducts2,3,4,5. Here we describe prime editing, a versatile and precise genome editing method that directly writes new genetic information into a specified DNA site using a catalytically impaired Cas9 endonuclease fused to an engineered reverse transcriptase, programmed with a prime editing guide RNA (pegRNA) that both specifies the target site and encodes the desired edit. We performed more than 175 edits in human cells, including targeted insertions, deletions, and all 12 types of point mutation, without requiring double-strand breaks or donor DNA templates. We used prime editing in human cells to correct, efficiently and with few byproducts, the primary genetic causes of sickle cell disease (requiring a transversion in HBB) and Tay–Sachs disease (requiring a deletion in HEXA); to install a protective transversion in PRNP; and to insert various tags and epitopes precisely into target loci. Four human cell lines and primary post-mitotic mouse cortical neurons support prime editing with varying efficiencies. Prime editing shows higher or similar efficiency and fewer byproducts than homology-directed repair, has complementary strengths and weaknesses compared to base editing, and induces much lower off-target editing than Cas9 nuclease at known Cas9 off-target sites. Prime editing substantially expands the scope and capabilities of genome editing, and in principle could correct up to 89% of known genetic variants associated with human diseases.

 

 

From Anzolone et al. Nature 2019 Figure 1.

Prime editing strategy

Cas9 targets DNA using a guide RNA containing a spacer sequence that hybridizes to the target DNA site. We envisioned the generation of guide RNAs that both specify the DNA target and contain new genetic information that replaces target DNA nucleotides. To transfer information from these engineered guide RNAs to target DNA, we proposed that genomic DNA, nicked at the target site to expose a 3′-hydroxyl group, could be used to prime the reverse transcription of an edit-encoding extension on the engineered guide RNA (the pegRNA) directly into the target site (Fig. 1b, cSupplementary Discussion).

These initial steps result in a branched intermediate with two redundant single-stranded DNA flaps: a 5′ flap that contains the unedited DNA sequence and a 3′ flap that contains the edited sequence copied from the pegRNA (Fig. 1c). Although hybridization of the perfectly complementary 5′ flap to the unedited strand is likely to be thermodynamically favoured, 5′ flaps are the preferred substrate for structure-specific endonucleases such as FEN122, which excises 5′ flaps generated during lagging-strand DNA synthesis and long-patch base excision repair. The redundant unedited DNA may also be removed by 5′ exonucleases such as EXO123.

  • The authors reasoned that preferential 5′ flap excision and 3′ flap ligation could drive the incorporation of the edited DNA strand, creating heteroduplex DNA containing one edited strand and one unedited strand (Fig. 1c).
  • DNA repair to resolve the heteroduplex by copying the information in the edited strand to the complementary strand would permanently install the edit (Fig. 1c).
  • They had hypothesized that nicking the non-edited DNA strand might bias DNA repair to preferentially replace the non-edited strand.

Results

  • The authors evaluated the eukaryotic cell DNA repair outcomes of 3′ flaps produced by pegRNA-programmed reverse transcription in vitro, and performed in vitro prime editing on reporter plasmids, then transformed the reaction products into yeast cells (Extended Data Fig. 2).
  • Reporter plasmids encoding EGFP and mCherry separated by a linker containing an in-frame stop codon, +1 frameshift, or −1 frameshift were constructed and when plasmids were edited in vitro with Cas9 nickase, RT, and 3′-extended pegRNAs encoding a transversion that corrects the premature stop codon, 37% of yeast transformants expressed both GFP and mCherry (Fig. 1f, Extended Data Fig. 2).
  • They fused a variant of M—MLV-RT (reverse transcriptase) to Cas9 with an extended linker and this M-MLV RT fused to the C terminus of Cas9(H840A) nickase was designated as PE1. This strategy allowed the authors to generate a cell line containing all the required components of the primer editing system. They constructed 19 variants of PE1 containing a variety of RT mutations to evaluate their editing efficiency in human cells
  • Generated a pentamutant RT incorporated into PE1 (Cas9(H840A)–M-MLV RT(D200N/L603W/T330P/T306K/W313F)) is hereafter referred to as prime editor 2 (PE2).  These were more thermostable versions of RT with higher efficiency.
  • Optimized the guide (pegRNA) using a series of permutations and  recommend starting with about 10–16 nt and testing shorter and longer RT templates during pegRNA optimization.
  • In the previous attempts (PE1 and PE2 systems), mismatch repair resolves the heteroduplex to give either edited or non-edited products. So they next developed an optimal editing system (PE3) to produce optimal nickase activity and found nicks positioned 3′ of the edit about 40–90 bp from the pegRNA-induced nick generally increased editing efficiency (averaging 41%) without excess indel formation (6.8% average indels for the sgRNA with the highest editing efficiency) (Fig. 3b).
  • The cell line used to finalize and validate the system was predominantly HEK293T immortalized cell line
  • Together, their findings establish that PE3 systems improve editing efficiencies about threefold compared with PE2, albeit with a higher range of indels than PE2. When it is possible to nick the non-edited strand with an sgRNA that requires editing before nicking, the PE3b system offers PE3-like editing levels while greatly reducing indel formation.
  • Off Target Effects: Strikingly, PE3 or PE2 with the same 16 pegRNAs containing these four target spacers resulted in detectable off-target editing at only 3 out of 16 off-target sites, with only 1 of 16 showing an off-target editing efficiency of 1% or more (Extended Data Fig. 6h). Average off-target prime editing for pegRNAs targeting HEK3HEK4EMX1, and FANCFat the top four known Cas9 off-target sites for each protospacer was <0.1%, <2.2 ± 5.2%, <0.1%, and <0.13 ± 0.11%, respectively (Extended Data Fig. 6h).
  • The PE3 system was very efficient at editing the most common mutation that causes Tay-Sachs disease, a 4-bp insertion in HEXA(HEXA1278+TATC).

References

  1. Landrum, M. J. et al. ClinVar: public archive of interpretations of clinically relevant variants. Nucleic Acids Res44, D862–D868 (2016).
  2. Jinek, M. et al. A programmable dual-RNA-guided DNA endonuclease in adaptive bacterial immunity. Science337, 816–821 (2012).
  3. Cong, L. et al. Multiplex genome engineering using CRISPR/Cas systems. Science339, 819–823 (2013).

 

  1. Mali, P. et al. RNA-guided human genome engineering via Cas9. Science339, 823–826 (2013).
  2. Kosicki, M., Tomberg, K. & Bradley, A. Repair of double-strand breaks induced by CRISPR–Cas9 leads to large deletions and complex rearrangements.  Biotechnol. 36, 765–771 (2018).
  3. Anzalone, A.V., Randolph, P.B., Davis, J.R. et al.Search-and-replace genome editing without double-strand breaks or donor DNA. Nature576, 149–157 (2019). https://doi.org/10.1038/s41586-019-1711-4

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Did FDA Reverse Course on Convalescent Plasma Therapy for COVID-19?

Reporter: Stephen J. Williams, PhD

 

Starting with a timeline of recent announcements by the FDA on convalescent plasma therapy

April 16, 2020

FDA STATEMENT

Coronavirus (COVID-19) Update: FDA Encourages Recovered Patients to Donate Plasma for Development of Blood-Related Therapies

 

As part of the all-of-America approach to fighting the COVID-19 pandemic, the U.S. Food and Drug Administration has been working with partners across the U.S. government, academia and industry to expedite the development and availability of critical medical products to treat this novel virus. Today, we are providing an update on one potential treatment called convalescent plasma and encouraging those who have recovered from COVID-19 to donate plasma to help others fight this disease.

Convalescent plasma is an antibody-rich product made from blood donated by people who have recovered from the disease caused by the virus. Prior experience with respiratory viruses and limited data that have emerged from China suggest that convalescent plasma has the potential to lessen the severity or shorten the length of illness caused by COVID-19. It is important that we evaluate this potential therapy in the context of clinical trials, through expanded access, as well as facilitate emergency access for individual patients, as appropriate.

The response to the agency’s recently announced national efforts to facilitate the development of and access to convalescent plasma has been tremendous. More than 1,040 sites and 950 physician investigators nationwide have signed on to participate in the Mayo Clinic-led expanded access protocol. A number of clinical trials are also taking place to evaluate the safety and efficacy of convalescent plasma and the FDA has granted numerous single patient emergency investigational new drug (eIND) applications as well.

Source: https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-encourages-recovered-patients-donate-plasma-development-blood

August 23, 2020

 

Recommendations for Investigational COVID-19 Convalescent Plasma

 

  • FDA issues guidelines on clinical trials and obtaining emergency enrollment concerning convalescent plasma

FDA has issued guidance to provide recommendations to health care providers and investigators on the administration and study of investigational convalescent plasma collected from individuals who have recovered from COVID-19 (COVID-19 convalescent plasma) during the public health emergency.

The guidance provides recommendations on the following:

Because COVID-19 convalescent plasma has not yet been approved for use by FDA, it is regulated as an investigational product.  A health care provider must participate in one of the pathways described below.  FDA does not collect COVID-19 convalescent plasma or provide COVID-19 convalescent plasma.  Health care providers or acute care facilities should instead obtain COVID-19 convalescent plasma from an FDA-registered blood establishment.

Excerpts from the guidance document are provided below.

Background

The Food and Drug Administration (FDA or Agency) plays a critical role in protecting the United States (U.S.) from threats including emerging infectious diseases, such as the Coronavirus Disease 2019 (COVID-19) pandemic.  FDA is committed to providing timely guidance to support response efforts to this pandemic.

One investigational treatment being explored for COVID-19 is the use of convalescent plasma collected from individuals who have recovered from COVID-19.  Convalescent plasma that contains antibodies to severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2 (the virus that causes COVID-19) is being studied for administration to patients with COVID-19. Use of convalescent plasma has been studied in outbreaks of other respiratory infections, including the 2003 SARS-CoV-1 epidemic, the 2009-2010 H1N1 influenza virus pandemic, and the 2012 MERS-CoV epidemic.

Although promising, convalescent plasma has not yet been shown to be safe and effective as a treatment for COVID-19. Therefore, it is important to study the safety and efficacy of COVID-19 convalescent plasma in clinical trials.

Pathways for Use of Investigational COVID-19 Convalescent Plasma

The following pathways are available for administering or studying the use of COVID-19 convalescent plasma:

  1. Clinical Trials

Investigators wishing to study the use of convalescent plasma in a clinical trial should submit requests to FDA for investigational use under the traditional IND regulatory pathway (21 CFR Part 312). CBER’s Office of Blood Research and Review is committed to engaging with sponsors and reviewing such requests expeditiously. During the COVID-19 pandemic, INDs may be submitted via email to CBERDCC_eMailSub@fda.hhs.gov.

  1. Expanded Access

An IND application for expanded access is an alternative for use of COVID-19 convalescent plasma for patients with serious or immediately life-threatening COVID-19 disease who are not eligible or who are unable to participate in randomized clinical trials (21 CFR 312.305). FDA has worked with multiple federal partners and academia to open an expanded access protocol to facilitate access to COVID-19 convalescent plasma across the nation. Access to this investigational product may be available through participation of acute care facilities in an investigational expanded access protocol under an IND that is already in place.

Currently, the following protocol is in place: National Expanded Access Treatment Protocol

  1. Single Patient Emergency IND

Although participation in clinical trials or an expanded access program are ways for patients to obtain access to convalescent plasma, for various reasons these may not be readily available to all patients in potential need. Therefore, given the public health emergency that the COVID-19 pandemic presents, and while clinical trials are being conducted and a national expanded access protocol is available, FDA also is facilitating access to COVID-19 convalescent plasma for use in patients with serious or immediately life-threatening COVID-19 infections through the process of the patient’s physician requesting a single patient emergency IND (eIND) for the individual patient under 21 CFR 312.310. This process allows the use of an investigational drug for the treatment of an individual patient by a licensed physician upon FDA authorization, if the applicable regulatory criteria are met.  Note, in such case, a licensed physician seeking to administer COVID-19 convalescent plasma to an individual patient must request the eIND (see 21 CFR 312.310(b)).

To Obtain a Single Patient Emergency IND  

The requesting physician may contact FDA by completing Form FDA 3926 (https://www.fda.gov/media/98616/download) and submitting the form by email to CBER_eIND_Covid-19@FDA.HHS.gov.

FACT SHEET FOR PATIENTS AND PARENTS/CAREGIVERS EMERGENCY USE AUTHORIZATION (EUA) OF COVID-19 CONVALESCENT PLASMA FOR TREATMENT OF COVID-19 IN HOSPITALIZED PATIENTS

  • FDA issues fact sheet for patients on donating plasma

August 23, 2020

 

FDA Issues Emergency Use Authorization for Convalescent Plasma as Potential Promising COVID–19 Treatment, Another Achievement in Administration’s Fight Against Pandemic

 

Today, the U.S. Food and Drug Administration issued an emergency use authorization (EUA) for investigational convalescent plasma for the treatment of COVID-19 in hospitalized patients as part of the agency’s ongoing efforts to fight COVID-19. Based on scientific evidence available, the FDA concluded, as outlined in its decision memorandum, this product may be effective in treating COVID-19 and that the known and potential benefits of the product outweigh the known and potential risks of the product.

Today’s action follows the FDA’s extensive review of the science and data generated over the past several months stemming from efforts to facilitate emergency access to convalescent plasma for patients as clinical trials to definitively demonstrate safety and efficacy remain ongoing.

The EUA authorizes the distribution of COVID-19 convalescent plasma in the U.S. and its administration by health care providers, as appropriate, to treat suspected or laboratory-confirmed COVID-19 in hospitalized patients with COVID-19.

Alex Azar, Health and Human Services Secretary:
“The FDA’s emergency authorization for convalescent plasma is a milestone achievement in President Trump’s efforts to save lives from COVID-19,” said Secretary Azar. “The Trump Administration recognized the potential of convalescent plasma early on. Months ago, the FDA, BARDA, and private partners began work on making this product available across the country while continuing to evaluate data through clinical trials. Our work on convalescent plasma has delivered broader access to the product than is available in any other country and reached more than 70,000 American patients so far. We are deeply grateful to Americans who have already donated and encourage individuals who have recovered from COVID-19 to consider donating convalescent plasma.”

Stephen M. Hahn, M.D., FDA Commissioner:
“I am committed to releasing safe and potentially helpful treatments for COVID-19 as quickly as possible in order to save lives. We’re encouraged by the early promising data that we’ve seen about convalescent plasma. The data from studies conducted this year shows that plasma from patients who’ve recovered from COVID-19 has the potential to help treat those who are suffering from the effects of getting this terrible virus,” said Dr. Hahn. “At the same time, we will continue to work with researchers to continue randomized clinical trials to study the safety and effectiveness of convalescent plasma in treating patients infected with the novel coronavirus.”

Scientific Evidence on Convalescent Plasma

Based on an evaluation of the EUA criteria and the totality of the available scientific evidence, the FDA’s Center for Biologics Evaluation and Research determined that the statutory criteria for issuing an EUA criteria were met.

The FDA determined that it is reasonable to believe that COVID-19 convalescent plasma may be effective in lessening the severity or shortening the length of COVID-19 illness in some hospitalized patients. The agency also determined that the known and potential benefits of the product, when used to treat COVID-19, outweigh the known and potential risks of the product and that that there are no adequate, approved, and available alternative treatments.

 

August 24, 2020

Donate COVID-19 Plasma

 

  • FDA posts video and blog about how to donate plasms if you had been infected with COVID

 

https://youtu.be/PlX15rWdBbY

 

 

Please go to https://www.fda.gov/emergency-preparedness-and-response/coronavirus-disease-2019-covid-19/donate-covid-19-plasma

to read more from FDA

 

 

August 25, 2020

 

CLINICAL MEMORANDUM From: , OBRR/DBCD/CRS To: , OBRR Through: , OBRR/DBCD , OBRR/DBCD , OBRR/DBCD/CRS Re: EUA 26382: Emergency Use Authorization (EUA) Request (original request 8/12/20; amended request 8/23/20) Product: COVID-19 Convalescent Plasma Items reviewed: EUA request Fact Sheet for Health Care Providers Fact Sheet for Recipients Sponsor: Robert Kadlec, M.D. Assistant Secretary for Preparedness and Response (ASPR) Office of Assistant Secretary for Preparedness and Response (ASPR) U.S. Department of Health and Human Services (HHS) EXECUTIVE SUMMARY COVID-19 Convalescent Plasma (CCP), an unapproved biological product, is proposed for use under an Emergency Use Authorization (EUA) under section 564 of the Federal Food, Drug, and Cosmetic Act (the Act),(21 USC 360bbb-3) as a passive immune therapy for the treatment of hospitalized patients with COVID-19, a serious or life-threatening disease. There currently is no adequate, approved, and available alternative to CCP for treating COVID-19. The sponsor has pointed to four lines of evidence to support that CCP may be effective in the treatment of hospitalized patients with COVID-19: 1) History of convalescent plasma for respiratory coronaviruses; 2) Evidence of preclinical safety and efficacy in animal models; 3) Published studies of the safety and efficacy of CCP; and 4) Data on safety and efficacy from the National Expanded Access Treatment Protocol (EAP) sponsored by the Mayo Clinic. Considering the totality of the scientific evidence presented in the EUA, I conclude that current data for the use of CCP in adult hospitalized patients with COVID-19 supports the conclusion that CCP meets the “may be effective” criterion for issuance of an EUA from section 564(c)(2)(A) of the Act. It is reasonable to conclude that the known and potential benefits of CCP outweigh the known and potential risks of CCP for the proposed EUA. Current data suggest the largest clinical benefit is associated with high-titer units of CCP administered early course of the disease.

Source: https://www.fda.gov/media/141480/download

 

And Today August 26, 2020

  • A letter, from Senator Warren, to Commissioner Hahn from Senate Committee asking for documentation for any communication between FDA and White House

August 25, 2020 Dr. Stephen M. Hahn, M.D. Commissioner of Food and Drugs U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 Dear Commissioner Hahn: We write regarding the U.S. Food and Drug Administration’s (FDA) troubling decision earlier this week to issue an Emergency Use Authorization (EUA) for convalescent plasma as a treatment for coronavirus disease 2019 (COVID-19).1 Reports suggests that the FDA granted the EUA amid intense political pressure from President Trump and other Administration officials, despite limited evidence of convalescent plasma’s effectiveness as a COVID-19 treatment.2 To help us better understand whether the issuance of the blood plasma EUA was motivated by politics, we request copies of any and all communications between FDA and White House officials regarding the blood plasma EUA.

Source: https://www.warren.senate.gov/imo/media/doc/2020.08.25%20Letter%20to%20FDA%20re%20Blood%20Plasma%20EUA.pdf

…….. which may have been a response to this article

FDA chief walks back comments on effectiveness of coronavirus plasma treatment

 

From CNBC: https://www.cnbc.com/2020/08/25/fda-chief-walks-back-comments-on-effectiveness-of-coronavirus-plasma-treatment.html

PUBLISHED TUE, AUG 25 202010:45 AM EDTUPDATED TUE, AUG 25 20204:12 PM EDT

Berkeley Lovelace Jr.@BERKELEYJR

Will Feuer@WILLFOIA

KEY POINTS

  • The authorization will allow health-care providers in the U.S. to use the plasma to treat hospitalized patients with Covid-19.
  • The FDA’s emergency use authorization came a day after President Trump accused the agency of delaying enrollment in clinical trials for vaccines or therapeutics.
  • The criticism from Trump and action from the FDA led some scientists to believe the authorization, which came on the eve of the GOP national convention, was politically motivated.

FDA Commissioner Dr. Stephen Hahn is walking back comments on the benefits of convalescent plasma, saying he could have done a better job of explaining the data on its effectiveness against the coronavirus after authorizing it for emergency use over the weekend.

Commisioners responses over Twitter

https://twitter.com/SteveFDA/status/1298071603675373569?s=20

https://twitter.com/SteveFDA/status/1298071619236245504?s=20

August 26, 2020

In an interview with Bloomberg’s , FDA Commissioner Hahn reiterates that his decision was based on hard evidence and scientific fact, not political pressure.  The whole interview is at the link below:

https://www.bloomberg.com/news/articles/2020-08-25/fda-s-hahn-vows-to-stick-to-the-science-amid-vaccine-pressure?sref=yLCixKPR

Some key points:

  • Dr. Hahn corrected his initial statement about 35% of people would be cured by convalescent plasma. In the interview he stated:

I was trying to do what I do with patients, because patients often understand things in absolute terms versus relative terms. And I should’ve been more careful, there’s no question about it. What I was trying to get to is that if you look at a hundred patients who receive high titre, and a hundred patients who received low titre, the difference between those two particular subset of patients who had these specific criteria was a 35% reduction in mortality. So I frankly did not do a good job of explaining that.

  • FDA colleagues had frank discussion after the statement was made.  He is not asking for other people in HHS to retract their statements, only is concerned that FDA has correct information for physicians and patients
  • Hahn is worried that people will not enroll due to chance they may be given placebo
  • He gave no opinion when asked if FDA should be an independent agency

 

For more articles on COVID19 please go to our Coronavirus Portal at

https://pharmaceuticalintelligence.com/coronavirus-portal/

 

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RNA from the SARS-CoV-2 virus taking over the cells it infects: Virulence – Pathogen’s ability to infect a Resistant Host: The Imbalance between Controlling Virus Replication versus Activation of the Adaptive Immune Response

Curator: Aviva Lev-Ari, PhD, RN – I added colors and bold face

 

UPDATED on 9/8/2020

What bats can teach us about developing immunity to Covid-19 | Free to read

Clive Cookson, Anna Gross and Ian Bott, London

https://www.ft.com/content/743ce7a0-60eb-482d-b1f4-d4de11182fa9?utm_source=Nature+Briefing&utm_campaign=af64422080-briefing-dy-20200908&utm_medium=email&utm_term=0_c9dfd39373-af64422080-43323101

 

UPDATED on 6/29/2020

Another duality and paradox in the Treatment of COVID-19 Patients in ICUs was expressed by Mike Yoffe, MD, PhD, David H. Koch Professor of Biology and Biological Engineering, Massachusetts Institute of Technology. Dr. Yaffe has a joint appointment in Acute Care Surgery, Trauma, and Surgical Critical Care, and in Surgical Oncology @BIDMC

on 6/29 at SOLUTIONS with/in/sight at Koch Institute @MIT

How Are Cancer Researchers Fighting COVID-19? (Part II)” Jun 29, 2020 11:30 AM EST

Mike Yoffe, MD, PhD 

In COVID-19 patients: two life threatening conditions are seen in ICUs:

  • Blood Clotting – Hypercoagulability or Thrombophilia
  • Cytokine Storm – immuno-inflammatory response
  • The coexistence of 1 and 2 – HINDERS the ability to use effectively tPA as an anti-clotting agent while the cytokine storm is present.

Mike Yoffe’s related domain of expertise:

Signaling pathways and networks that control cytokine responses and inflammation

Misregulation of cytokine feedback loops, along with inappropriate activation of the blood clotting cascade causes dysregulation of cell signaling pathways in innate immune cells (neutrophils and macrophages), resulting in tissue damage and multiple organ failure following trauma or sepsis. Our research is focused on understanding the role of the p38-MK2 pathway in cytokine control and innate immune function, and on cross-talk between cytokines, clotting factors, and neutrophil NADPH oxidase-derived ROS in tissue damage, coagulopathy, and inflammation, using biochemistry, cell biology, and mouse knock-out/knock-in models.  We recently discovered a particularly important link between abnormal blood clotting and the complement pathway cytokine C5a which causes excessive production of extracellular ROS and organ damage by neutrophils after traumatic injury.

SOURCE

https://www.bidmc.org/research/research-by-department/surgery/acute-care-surgery-trauma-and-surgical-critical-care/michael-b-yaffe

 

See

The Genome Structure of CORONAVIRUS, SARS-CoV-2

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2020/05/04/the-genome-structure-of-coronavirus-sars-cov-2-i-awaited-for-this-article-for-60-days/

 

Imbalanced Host Response to SARS-CoV-2 Drives Development of COVID-19

Open Access Published:May 15, 2020DOI:https://doi.org/10.1016/j.cell.2020.04.026

Highlights

  • SARS-CoV-2 infection induces low IFN-I and -III levels with a moderate ISG response
  • Strong chemokine expression is consistent across in vitroex vivo, and in vivo models
  • Low innate antiviral defenses and high pro-inflammatory cues contribute to COVID-19

Summary

Viral pandemics, such as the one caused by SARS-CoV-2, pose an imminent threat to humanity. Because of its recent emergence, there is a paucity of information regarding viral behavior and host response following SARS-CoV-2 infection. Here we offer an in-depth analysis of the transcriptional response to SARS-CoV-2 compared with other respiratory viruses. Cell and animal models of SARS-CoV-2 infection, in addition to transcriptional and serum profiling of COVID-19 patients, consistently revealed a unique and inappropriate inflammatory response. This response is defined by low levels of type I and III interferons juxtaposed to elevated chemokines and high expression of IL-6. We propose that reduced innate antiviral defenses coupled with exuberant inflammatory cytokine production are the defining and driving features of COVID-19.

Graphical Abstract

Keywords

Results

Defining the Transcriptional Response to SARS-CoV-2 Relative to Other Respiratory Viruses

To compare the transcriptional response of SARS-CoV-2 with other respiratory viruses, including MERS-CoV, SARS-CoV-1, human parainfluenza virus 3 (HPIV3), respiratory syncytial virus (RSV), and IAV, we first chose to focus on infection in a variety of respiratory cell lines (Figure 1). To this end, we collected poly(A) RNA from infected cells and performed RNA sequencing (RNA-seq) to estimate viral load. These data show that virus infection levels ranged from 0.1% to more than 50% of total RNA reads (Figure 1A).

Discussion

In the present study, we focus on defining the host response to SARS-CoV-2 and other human respiratory viruses in cell lines, primary cell cultures, ferrets, and COVID-19 patients. In general, our data show that the overall transcriptional footprint of SARS-CoV-2 infection was distinct in comparison with other highly pathogenic coronaviruses and common respiratory viruses such as IAV, HPIV3, and RSV. It is noteworthy that, despite a reduced IFN-I and -III response to SARS-CoV-2, we observed a consistent chemokine signature. One exception to this observation is the response to high-MOI infection in A549-ACE2 and Calu-3 cells, where replication was robust and an IFN-I and -III signature could be observed. In both of these examples, cells were infected at a rate to theoretically deliver two functional virions per cell in addition to any defective interfering particles within the virus stock that were not accounted for by plaque assays. Under these conditions, the threshold for PAMP may be achieved prior to the ability of the virus to evade detection through production of a viral antagonist. Alternatively, addition of multiple genomes to a single cell may disrupt the stoichiometry of viral components, which, in turn, may itself generate PAMPs that would not form otherwise. These ideas are supported by the fact that, at a low-MOI infection in A549-ACE2 cells, high levels of replication could also be achieved, but in the absence of IFN-I and -III induction. Taken together, these data suggest that, at low MOIs, the virus is not a strong inducer of the IFN-I and -III system, as opposed to conditions where the MOI is high.
Taken together, the data presented here suggest that the response to SARS-CoV-2 is imbalanced with regard to controlling virus replication versus activation of the adaptive immune response. Given this dynamic, treatments for COVID-19 have less to do with the IFN response and more to do with controlling inflammation. Because our data suggest that numerous chemokines and ILs are elevated in COVID-19 patients, future efforts should focus on U.S. Food and Drug Administration (FDA)-approved drugs that can be rapidly deployed and have immunomodulating properties.

SOURCE

https://www.cell.com/cell/fulltext/S0092-8674(20)30489-X

SARS-CoV-2 ORF3b is a potent interferon antagonist whose activity is further increased by a naturally occurring elongation variant

Yoriyuki KonnoIzumi KimuraKeiya UriuMasaya FukushiTakashi IrieYoshio KoyanagiSo NakagawaKei Sato

Abstract

One of the features distinguishing SARS-CoV-2 from its more pathogenic counterpart SARS-CoV is the presence of premature stop codons in its ORF3b gene. Here, we show that SARS-CoV-2 ORF3b is a potent interferon antagonist, suppressing the induction of type I interferon more efficiently than its SARS-CoV ortholog. Phylogenetic analyses and functional assays revealed that SARS-CoV-2-related viruses from bats and pangolins also encode truncated ORF3b gene products with strong anti-interferon activity. Furthermore, analyses of more than 15,000 SARS-CoV-2 sequences identified a natural variant, in which a longer ORF3b reading frame was reconstituted. This variant was isolated from two patients with severe disease and further increased the ability of ORF3b to suppress interferon induction. Thus, our findings not only help to explain the poor interferon response in COVID-19 patients, but also describe a possibility of the emergence of natural SARS-CoV-2 quasi-species with extended ORF3b that may exacerbate COVID-19 symptoms.

Highlights

  • ORF3b of SARS-CoV-2 and related bat and pangolin viruses is a potent IFN antagonist

  • SARS-CoV-2 ORF3b suppresses IFN induction more efficiently than SARS-CoV ortholog

  • The anti-IFN activity of ORF3b depends on the length of its C-terminus

  • An ORF3b with increased IFN antagonism was isolated from two severe COVID-19 cases

Competing Interest Statement

The authors have declared no competing interest.

Paper in collection COVID-19 SARS-CoV-2 preprints from medRxiv and bioRxiv

 

SOURCE

https://www.biorxiv.org/content/10.1101/2020.05.11.088179v1

 

 

A deep dive into how the new coronavirus infects cells has found that it orchestrates a hostile takeover of their genes unlike any other known viruses do, producing what one leading scientist calls “unique” and “aberrant” changes.Recent studies show that in seizing control of genes in the human cells it invades, the virus changes how segments of DNA are read, doing so in a way that might explain why the elderly are more likely to die of Covid-19 and why antiviral drugs might not only save sick patients’ lives but also prevent severe disease if taken before infection.“It’s something I have never seen in my 20 years of” studying viruses, said virologist Benjamin tenOever of the Icahn School of Medicine at Mount Sinai, referring to how SARS-CoV-2, the virus that causes Covid-19, hijacks cells’ genomes.The “something” he and his colleagues saw is how SARS-CoV-2 blocks one virus-fighting set of genes but allows another set to launch, a pattern never seen with other viruses. Influenza and the original SARS virus (in the early 2000s), for instance, interfere with both arms of the body’s immune response — what tenOever dubs “call to arms” genes and “call for reinforcement” genes.The first group of genes produces interferons. These proteins, which infected cells release, are biological semaphores, signaling to neighboring cells to activate some 500 of their own genes that will slow down the virus’ ability to make millions of copies of itself if it invades them. This lasts seven to 10 days, tenOever said, controlling virus replication and thereby buying time for the second group of genes to act.This second set of genes produce their own secreted proteins, called chemokines, that emit a biochemical “come here!” alarm. When far-flung antibody-making B cells and virus-killing T cells sense the alarm, they race to its source. If all goes well, the first set of genes holds the virus at bay long enough for the lethal professional killers to arrive and start eradicating viruses.

“Most other viruses interfere with some aspect of both the call to arms and the call for reinforcements,” tenOever said. “If they didn’t, no one would ever get a viral illness”: The one-two punch would pummel any incipient infection into submission.

SARS-CoV-2, however, uniquely blocks one cellular defense but activates the other, he and his colleagues reported in a study published last week in Cell. They studied healthy human lung cells growing in lab dishes, ferrets (which the virus infects easily), and lung cells from Covid-19 patients. In all three, they found that within three days of infection, the virus induces cells’ call-for-reinforcement genes to produce cytokines. But it blocks their call-to-arms genes — the interferons that dampen the virus’ replication.

The result is essentially no brakes on the virus’s replication, but a storm of inflammatory molecules in the lungs, which is what tenOever calls an “unique” and “aberrant” consequence of how SARS-CoV-2 manipulates the genome of its target.

In another new study, scientists in Japan last week identified how SARS-CoV-2 accomplishes that genetic manipulation. Its ORF3b gene produces a protein called a transcription factor that has “strong anti-interferon activity,” Kei Sato of the University of Tokyo and colleagues found — stronger than the original SARS virus or influenza viruses. The protein basically blocks the cell from recognizing that a virus is present, in a way that prevents interferon genes from being expressed.

In fact, the Icahn School team found no interferons in the lung cells of Covid-19 patients. Without interferons, tenOever said, “there is nothing to stop the virus from replicating and festering in the lungs forever.”

That causes lung cells to emit even more “call-for-reinforcement” genes, summoning more and more immune cells. Now the lungs have macrophages and neutrophils and other immune cells “everywhere,” tenOever said, causing such runaway inflammation “that you start having inflammation that induces more inflammation.”

At the same time, unchecked viral replication kills lung cells involved in oxygen exchange. “And suddenly you’re in the hospital in severe respiratory distress,” he said.

In elderly people, as well as those with diabetes, heart disease, and other underlying conditions, the call-to-arms part of the immune system is weaker than in younger, healthier people, even before the coronavirus arrives. That reduces even further the cells’ ability to knock down virus replication with interferons, and imbalances the immune system toward the dangerous inflammatory response.

The discovery that SARS-CoV-2 strongly suppresses infected cells’ production of interferons has raised an intriguing possibility: that taking interferons might prevent severe Covid-19 or even prevent it in the first place, said Vineet Menachery of the University of Texas Medical Branch.

In a study of human cells growing in lab dishes, described in a preprint (not peer-reviewed or published in a journal yet), he and his colleagues also found that SARS-CoV-2 “prevents the vast amount” of interferon genes from turning on. But when cells growing in lab dishes received the interferon IFN-1 before exposure to the coronavirus, “the virus has a difficult time replicating.”

After a few days, the amount of virus in infected but interferon-treated cells was 1,000- to 10,000-fold lower than in infected cells not pre-treated with interferon. (The original SARS virus, in contrast, is insensitive to interferon.)

Ending the pandemic and preventing its return is assumed to require an effective vaccine to prevent infectionand antiviral drugs such as remdesivir to treat the very sick, but the genetic studies suggest a third strategy: preventive drugs.

It’s possible that treatment with so-called type-1 interferon “could stop the virus before it could get established,” Menachery said.

Giving drugs to healthy people is always a dicey proposition, since all drugs have side effects — something considered less acceptable than when a drug is used to treat an illness. “Interferon treatment is rife with complications,” Menachery warned. The various interferons, which are prescribed for hepatitis, cancers, and many other diseases, can cause flu-like symptoms.

But the risk-benefit equation might shift, both for individuals and for society, if interferons or antivirals or other medications are shown to reduce the risk of developing serious Covid-19 or even make any infection nearly asymptomatic.

Interferon “would be warning the cells the virus is coming,” Menachery said, so such pretreatment might “allow treated cells to fend off the virus better and limit its spread.” Determining that will of course require clinical trials, which are underway.

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A Series of Recently Published Papers Report the Development of SARS-CoV2 Neutralizing Antibodies and Passive Immunity toward COVID19

Curator: Stephen J. Williams, Ph.D.

 

Passive Immunity and Treatment of Infectious Diseases

The ability of one person to pass on immunity to another person (passive immunity) is one of the chief methods we develop immunity to many antigens.  For instance, maternal antibodies are passed to the offspring in the neonatal setting as well as in a mother’s milk during breast feeding.  In the clinical setting this is achieved by transferring antibodies from one patient who has been exposed to an antigen (like a virus) to the another individual.   However, the process of purifying the most efficacious antibody as well as its mass production is limiting due to its complexity and cost and can be prohibitively long delay during a pandemic outbreak, when therapies are few and needed immediately.  Regardless, the benefits of developing neutralizing antibodies to confer passive immunity versus development of a vaccine are evident, as the former takes considerable less time than development of a safe and effective vaccine.  For a good review on the development and use of neutralizing antibodies and the use of passive immunity to treat infectious diseases please read the following review:

Margaret A. Keller1,* and E. Richard Stiehm. Passive Immunity in Prevention and Treatment of Infectious Diseases. Clin Microbiol Rev. 2000 Oct; 13(4): 602–614. doi: 10.1128/cmr.13.4.602-614.2000

ABSTRACT

Antibodies have been used for over a century in the prevention and treatment of infectious disease. They are used most commonly for the prevention of measles, hepatitis A, hepatitis B, tetanus, varicella, rabies, and vaccinia. Although their use in the treatment of bacterial infection has largely been supplanted by antibiotics, antibodies remain a critical component of the treatment of diptheria, tetanus, and botulism. High-dose intravenous immunoglobulin can be used to treat certain viral infections in immunocompromised patients (e.g., cytomegalovirus, parvovirus B19, and enterovirus infections). Antibodies may also be of value in toxic shock syndrome, Ebola virus, and refractory staphylococcal infections. Palivizumab, the first monoclonal antibody licensed (in 1998) for an infectious disease, can prevent respiratory syncytial virus infection in high-risk infants. The development and use of additional monoclonal antibodies to key epitopes of microbial pathogens may further define protective humoral responses and lead to new approaches for the prevention and treatment of infectious diseases.

TABLE 1

Summary of the efficacy of antibody in the prevention and treatment of infectious diseases

Infection
Bacterial infections
 Respiratory infections (streptococcus, Streptococcus pneumoniaeNeisseria meningitisHaemophilus influenzae)
 Diphtheria
 Pertussis
 Tetanus
 Other clostridial infections
  C. botulinum
  C. difficile
 Staphylococcal infections
  Toxic shock syndrome
  Antibiotic resistance
  S. epidermidis in newborns
 Invasive streptococcal disease (toxic shock syndrome)
 High-risk newborns
 Shock, intensive care, and trauma
Pseudomonas infection
  Cystic Fibrosis
  Burns
Viral diseases
 Hepatitis A
 Hepatitis B
 Hepatitis C
 HIV infection
 RSV infection
 Herpesvirus infections
  CMV
  EBV
  HSV
  VZV
 Parvovirus infection
 Enterovirus infection
  In newborns
 Ebola
 Rabies
 Measles
 Rubella
 Mumps
 Tick-borne encephalitis
 Vaccinia

Go to:

A Great Explanation of Active versus Passive Immunity by Dr. John Campbell, one of the pioneers in the field of immunology:Antibodies have been used for over a century in the prevention and treatment of infectious disease. They are used most commonly for the prevention of measles, hepatitis A, hepatitis B, tetanus, varicella, rabies, and vaccinia. Although their use in the treatment of bacterial infection has largely been supplanted by antibiotics, antibodies remain a critical component of the treatment of diptheria, tetanus, and botulism. High-dose intravenous immunoglobulin can be used to treat certain viral infections in immunocompromised patients (e.g., cytomegalovirus, parvovirus B19, and enterovirus infections). Antibodies may also be of value in toxic shock syndrome, Ebola virus, and refractory staphylococcal infections. Palivizumab, the first monoclonal antibody licensed (in 1998) for an infectious disease, can prevent respiratory syncytial virus infection in high-risk infants. The development and use of additional monoclonal antibodies to key epitopes of microbial pathogens may further define protective humoral responses and lead to new approaches for the prevention and treatment of infectious diseases.

 

However, developing successful neutralizing antibodies can still be difficult but with the latest monoclonal antibody technology, as highlighted by the following papers, this process has made much more efficient.  In addition, it is not feasable to isolate antibodies from the plasma of covalescent patients in a scale that is needed for a worldwide outbreak.

A good explanation of the need can be found is Dr. Irina Robu’s post Race to develop antibody drugs for COVID-19 where:

When fighting off foreign invaders, our bodies make antibodies precisely produced for the task. The reason vaccines offer such long-lasting protection is they train the immune system to identify a pathogen, so immune cells remember and are ready to attack the virus when it appears. Monoclonal antibodies for coronavirus would take the place of the ones our bodies might produce to fight the disease. The manufactured antibodies would be infused into the body to either tamp down an existing infection, or to protect someone who has been exposed to the virus. However, these drugs are synthetic versions of the convalescent plasma treatments that rely on antibodies from people who have recovered from infection. But the engineered versions are easier to scale because they’re manufactured in rats, rather than from plasma donors.

The following papers represent the latest published work on development of therapeutic and prophylactic neutralizing antibodies to the coronavirus SARS-CoV2

1.  Cross-neutralization of SARS-CoV-2 by a human monoclonal SARS-CoV antibody.

Pinto, D., Park, Y., Beltramello, M. et al. Cross-neutralization of SARS-CoV-2 by a human monoclonal SARS-CoV antibody. Nature (2020).                                                                            https://doi.org/10.1038/s41586-020-2349-y

Abstract

SARS-CoV-2 is a newly emerged coronavirus responsible for the current COVID-19 pandemic that has resulted in more than 3.7 million infections and 260,000 deaths as of 6 May 20201,2. Vaccine and therapeutic discovery efforts are paramount to curb the pandemic spread of this zoonotic virus. The SARS-CoV-2 spike (S) glycoprotein promotes entry into host cells and is the main target of neutralizing antibodies. Here we describe multiple monoclonal antibodies targeting SARS-CoV-2 S identified from memory B cells of an individual who was infected with SARS-CoV in 2003. One antibody, named S309, potently neutralizes SARS-CoV-2 and SARS-CoV pseudoviruses as well as authentic SARS-CoV-2 by engaging the S receptor-binding domain. Using cryo-electron microscopy and binding assays, we show that S309 recognizes a glycan-containing epitope that is conserved within the sarbecovirus subgenus, without competing with receptor attachment. Antibody cocktails including S309 along with other antibodies identified here further enhanced SARS-CoV-2 neutralization and may limit the emergence of neutralization-escape mutants. These results pave the way for using S309- and S309-containing antibody cocktails for prophylaxis in individuals at high risk of exposure or as a post-exposure therapy to limit or treat severe disease.

 

2.  Potent neutralizing antibodies against SARS-CoV-2 identified by high-throughput single-cell sequencing of convalescent patients’ B cells

Yunlong Cao et al.  Potent neutralizing antibodies against SARS-CoV-2 identified by high-throughput single-cell sequencing of convalescent patients’ B cells. Cell (2020).

https://doi.org/10.1016/j.cell.2020.05.025

Summary

The COVID-19 pandemic urgently needs therapeutic and prophylactic interventions. Here we report the rapid identification of SARS-CoV-2 neutralizing antibodies by high-throughput single-cell RNA and VDJ sequencing of antigen-enriched B cells from 60 convalescent patients. From 8,558 antigen-binding IgG1+ clonotypes, 14 potent neutralizing antibodies were identified with the most potent one, BD-368-2, exhibiting an IC50 of 1.2 ng/mL and 15 ng/mL against pseudotyped and authentic SARS-CoV-2, respectively. BD-368-2 also displayed strong therapeutic and prophylactic efficacy in SARS-CoV-2-infected hACE2-transgenic mice. Additionally, the 3.8Å Cryo-EM structure of a neutralizing antibody in complex with the spike-ectodomain trimer revealed the antibody’s epitope overlaps with the ACE2 binding site. Moreover, we demonstrated that SARS-CoV-2 neutralizing antibodies could be directly selected based on similarities of their predicted CDR3H structures to those of SARS-CoV neutralizing antibodies. Altogether, we showed that human neutralizing antibodies could be efficiently discovered by high-throughput single B-cell sequencing in response to pandemic infectious diseases.

3. A human monoclonal antibody blocking SARS-CoV-2 infection

Wang, C., Li, W., Drabek, D. et al. A human monoclonal antibody blocking SARS-CoV-2 infection. Nat Commun 11, 2251 (2020). https://doi.org/10.1038/s41467-020-16256-y

Abstract

The emergence of the novel human coronavirus SARS-CoV-2 in Wuhan, China has caused a worldwide epidemic of respiratory disease (COVID-19). Vaccines and targeted therapeutics for treatment of this disease are currently lacking. Here we report a human monoclonal antibody that neutralizes SARS-CoV-2 (and SARS-CoV) in cell culture. This cross-neutralizing antibody targets a communal epitope on these viruses and may offer potential for prevention and treatment of COVID-19.

Extra References on Development of Neutralizing antibodies for COVID19 {Sars-CoV2} published this year (2020)  [1-4]

  1. Fan P, Chi X, Liu G, Zhang G, Chen Z, Liu Y, Fang T, Li J, Banadyga L, He S et al: Potent neutralizing monoclonal antibodies against Ebola virus isolated from vaccinated donors. mAbs 2020, 12(1):1742457.
  2. Dussupt V, Sankhala RS, Gromowski GD, Donofrio G, De La Barrera RA, Larocca RA, Zaky W, Mendez-Rivera L, Choe M, Davidson E et al: Potent Zika and dengue cross-neutralizing antibodies induced by Zika vaccination in a dengue-experienced donor. Nature medicine 2020, 26(2):228-235.
  3. Young CL, Lyons AC, Hsu WW, Vanlandingham DL, Park SL, Bilyeu AN, Ayers VB, Hettenbach SM, Zelenka AM, Cool KR et al: Protection of swine by potent neutralizing anti-Japanese encephalitis virus monoclonal antibodies derived from vaccination. Antiviral research 2020, 174:104675.
  4. Sautto GA, Kirchenbaum GA, Abreu RB, Ecker JW, Pierce SR, Kleanthous H, Ross TM: A Computationally Optimized Broadly Reactive Antigen Subtype-Specific Influenza Vaccine Strategy Elicits Unique Potent Broadly Neutralizing Antibodies against Hemagglutinin. J Immunol 2020, 204(2):375-385.

 

For More Articles on COVID-19 Please see Our Coronavirus Portal on this Open Access Scientific Journal at:

https://pharmaceuticalintelligence.com/coronavirus-portal/

and the following Articles on  Immunity at

Race to develop antibody drugs for COVID-19
Bispecific and Trispecific Engagers: NK-T Cells and Cancer Therapy
Issues Need to be Resolved With ImmunoModulatory Therapies: NK cells, mAbs, and adoptive T cells
Antibody-bound Viral Antigens

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Live Notes, Real Time Conference Coverage 2020 AACR Virtual Meeting April 28, 2020 Symposium: New Drugs on the Horizon Part 3 12:30-1:25 PM

Reporter: Stephen J. Williams, PhD

New Drugs on the Horizon: Part 3
Introduction

Andrew J. Phillips, C4 Therapeutics

  • symposium brought by AACR CICR and had about 30 proposals for talks and chose three talks
  • unfortunately the networking event is not possible but hope to see you soon in good health

ABBV-184: A novel survivin specific T cell receptor/CD3 bispecific therapeutic that targets both solid tumor and hematological malignancies

Edward B Reilly
AbbVie Inc. @abbvie

  • T-cell receptors (TCR) can recognize the intracellular targets whereas antibodies only recognize the 25% of potential extracellular targets
  • survivin is expressed in multiple cancers and correlates with poor survival and prognosis
  • CD3 bispecific TCR to survivn (Ab to CD3 on T- cells and TCR to survivin on cancer cells presented in MHC Class A3)
  • ABBV184  effective in vivo in lung cancer models as single agent;
  • in humanized mouse tumor models CD3/survivin bispecific can recruit T cells into solid tumors; multiple immune cells CD4 and CD8 positive T cells were found to infiltrate into tumor
  • therapeutic window as measured by cytokine release assays in tumor vs. normal cells very wide (>25 fold)
  • ABBV184 does not bind platelets and has good in vivo safety profile
  • First- in human dose determination trial: used in vitro cancer cell assays to determine 1st human dose
  • looking at AML and lung cancer indications
  • phase 1 trial is underway for safety and efficacy and determine phase 2 dose
  • survivin has very few mutations so they are not worried about a changing epitope of their target TCR peptide of choice

The discovery of TNO155: A first in class SHP2 inhibitor

Matthew J. LaMarche
Novartis @Novartis

  • SHP2 is an intracellular phosphatase that is upstream of MEK ERK pathway; has an SH2 domain and PTP domain
  • knockdown of SHP2 inhibits tumor growth and colony formation in soft agar
  • 55 TKIs there are very little phosphatase inhibitors; difficult to target the active catalytic site; inhibitors can be oxidized at the active site; so they tried to target the two domains and developed an allosteric inhibitor at binding site where three domains come together and stabilize it
  • they produced a number of chemical scaffolds that would bind and stabilize this allosteric site
  • block the redox reaction by blocking the cysteine in the binding site
  • lead compound had phototoxicity; used SAR analysis to improve affinity and reduce phototox effects
  • was very difficult to balance efficacy, binding properties, and tox by adjusting stuctures
  • TNO155 is their lead into trials
  • SHP2 expressed in T cells and they find good combo with I/O with uptick of CD8 cells
  • TNO155 is very selective no SHP1 inhibition; SHP2 can autoinhibit itself when three domains come together and stabilize; no cross reactivity with other phosphatases
  • they screened 1.5 million compounds and got low hit rate so that is why they needed to chemically engineer and improve on the classes they found as near hits

Closing Remarks

 

Xiaojing Wang
Genentech, Inc. @genentech

Follow on Twitter at:

@pharma_BI

@AACR

@CureCancerNow

@pharmanews

@BiotechWorld

@HopkinsMedicine

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Live Notes, Real Time Conference Coverage 2020 AACR Virtual Meeting April 27, 2020 Minisymposium on Drugging Undrugged Cancer Targets 1:30 pm – 5:00 pm

SESSION VMS.ET01.01 – Drugging Undrugged Cancer Targets

April 27, 2020, 1:30 PM – 3:30 PM
Virtual Meeting: All Session Times Are U.S. EDT

Session Type
Virtual Minisymposium
Track(s)
Experimental and Molecular Therapeutics,Drug Development
18 Presentations
1:30 PM – 1:30 PM
– ChairpersonPeter C. Lucas. University of Pittsburgh School of Medicine, Pittsburgh, PA

1:30 PM – 1:30 PM
– ChairpersonJohn S. Lazo. University of Virginia, Charlottesville, VA

1:30 PM – 1:35 PM
– IntroductionPeter C. Lucas. University of Pittsburgh School of Medicine, Pittsburgh, PA

1:35 PM – 1:45 PM
3398 – PTPN22 is a systemic target for augmenting antitumor immunityWon Jin Ho, Jianping Lin, Ludmila Danilova, Zaw Phyo, Soren Charmsaz, Aditya Mohan, Todd Armstrong, Ben H. Park, Elana J. Fertig, Zhong-Yin Zhang, Elizabeth M. Jaffee. Johns Hopkins Sidney Kimmel Comp. Cancer Center, Baltimore, MD, Purdue University, Baltimore, MD, Johns Hopkins Sidney Kimmel Comp. Cancer Center, Baltimore, MD, Vanderbilt University Medical Center, Baltimore, MD

Abstract: Remarkable progress in cancer immunology has revolutionized cancer therapy. The majority of patients, however, do not respond to immunotherapeutic options, warranting the ongoing search for better strategies. Leveraging the established role of protein tyrosine phosphatase non-receptor type 22 (PTPN22) in autoimmune diseases, we hypothesized that PTPN22 is a novel target for cancer immunotherapy. PTPN22 is a physiologic regulator of T cell receptor (TCR) signaling acting by dephosphorylating activating tyrosine residues in Lck and Zap70. We first confirmed the relevance of PTPN22 expression by exploring its expression in multiple human cancer types using The Cancer Genome Atlas (TCGA). PTPN22 expression positively correlated with T cell and M1 macrophage gene signatures and immune regulatory genes, especially inflamed tumor types. Next, we directly investigated the role of PTPN22 in antitumor immunity by comparing in vivo tumor characteristics in wild-type (WT) and PTPN22 knockout (KO) mice. Consistent with our hypothesis, PTPN22 KO mice resisted MC38 and EG7 tumors significantly compared with WT. Mass cytometry (CyTOF) profiling of the immune tumor microenvironment demonstrated that MC38 tumors in PTPN22 KO mice were infiltrated with greater numbers of T cells, particularly CD8+ T cells expressing granzyme B and PD1. To further delineate the effects of PTPN22 KO on TCR signaling, we established an optimized CyTOF panel of 9 phosphorylation sites involved in the TCR signaling pathway, including two enzymatic substrates of PTPN22 (Lck Y394 and Zap70 Y493) and 15 immune subtyping markers. CyTOF phospho-profiling of CD8 T cells from tumor-bearing mouse spleens and the peripheral blood of immunotherapy-naïve cancer patients showed that the phosphorylated state of Zap70 Y493 correlated strongly with granzyme B expression. Furthermore, phospho-profiling of tumor-infiltrating CD8+ T cells (a measure of T cell activation) revealed the highest TCR-pathway phosphorylation levels in memory CD8+ T cells that express PD1. The difference in phosphorylation levels between WT and PTPN22 KO was most pronounced for Lck Y394. Based on these findings, we then hypothesized that PD1 inhibition will further enhance the antitumor immune responses promoted by the lack of PTPN22. Indeed, PTPN22 KO mice bearing MC38 and EG7 tumors responded more significantly to anti-PD1 therapy when compared with tumor-bearing WT mice. Finally, we treated WT tumor bearing mice with two different small molecule inhibitors of PTPN22, one previously published compound, LTV1, and one novel compound, L1 (discovered through structure based synthesis). While both inhibitors phenocopied the PTPN22 KO mice in resisting MC38 tumor growth, L1 treatment gave an immune profile that resembled what was observed in tumor-bearing PTPN22 KO mice. Taken together, our results demonstrate that PTPN22 is a novel systemic target for augmenting antitumor immunity.

  • can they leverage autoimmune data to look at new targets for checkpoint inhibition; we have a long way to go in immunooncology as only less than 30-40% of cancer types respond
  • using Cancer Genome Atlas PTPN22 is associated with autoimmune disorders
  • PTPN22 KO increases many immune cells; macrophages t-cells and when KO in tumors get more t cell infiltrate
  • PTP KO enhances t cell response, and may be driving t cells to exhaustion
  • made a inhibitor or PTPN22; antitumor phenotype when given inhibitor was like KO mice; a PDL1 inhibitor worked in KO mice
  • PTPN22 only in select hematopoetic cells

1:45 PM – 1:50 PM
– Discussion

1:50 PM – 2:00 PM
3399 – Preclinical evaluation of eFT226, a potent and selective eIF4A inhibitor with anti-tumor activity in FGFR1,2 and HER2 driven cancers. Peggy A. Thompson, Nathan P. Young, Adina Gerson-Gurwitz, Boreth Eam, Vikas Goel, Craig R. Stumpf, Joan Chen, Gregory S. Parker, Sarah Fish, Maria Barrera, Eric Sung, Jocelyn Staunton, Gary G. Chiang, Kevin R. Webster. eFFECTOR Therapeutics, San Diego, CA @RuggeroDavide

Abstract: Mutations or amplifications affecting receptor tyrosine kinases (RTKs) activate the RAS/MAPK and PI3K/AKT signaling pathways thereby promoting cancer cell proliferation and survival. Oncoprotein expression is tightly controlled at the level of mRNA translation and is regulated by the eukaryotic translation initiation factor 4F (eIF4F) complex consisting of eIF4A, eIF4E, and eIF4G. eIF4A functions to catalyze the unwinding of secondary structure in the 5’-untranslated region (5’-UTR) of mRNA facilitating ribosome scanning and translation initiation. The activation of oncogenic signaling pathways, including RAS and PI3K, facilitate formation of eIF4F and enhance eIF4A activity promoting the translation of oncogenes with highly structured 5’-UTRs that are required for tumor cell proliferation, survival and metastasis. eFT226 is a selective eIF4A inhibitor that converts eIF4A into a sequence specific translational repressor by increasing the affinity between eIF4A and 5’-UTR polypurine motifs leading to selective downregulation of mRNA translation. The polypurine element is highly enriched in the 5’-UTR of eFT226 target genes, many of which are known oncogenic drivers, including FGFR1,2 and HER2, enabling eFT226 to selectively inhibit dysregulated oncogene expression. Formation of a ternary complex [eIF4A-eFT226-mRNA] blocks ribosome scanning along the 5’-UTR leading to dose dependent inhibition of RTK protein expression. The 5’-UTR sequence dependency of eFT226 translational inhibition was evaluated in cell-based reporter assays demonstrating 10-45-fold greater sensitivity for reporter constructs containing an RTK 5’-UTR compared to a control. In solid tumor cell lines driven by alterations in FGFR1, FGFR2 or HER2, downregulation of RTK expression by eFT226 resulted in decreased MAPK and AKT signaling, potent inhibition of cell proliferation and an induction of apoptosis suggesting that eFT226 could be effective in treating tumor types dependent on these oncogenic drivers. Solid tumor xenograft models harboring FGFR1,2 or HER2 amplifications treated with eFT226 resulted in significant in vivo tumor growth inhibition and regression at well tolerated doses in breast, non-small cell lung and colorectal cancer models. Treatment with eFT226 also decreased RTK protein levels supporting the potential to use these eFT226 target genes as pharmacodynamic markers of target engagement. Further evaluation of predictive markers of sensitivity or resistance showed that RTK tumor models with mTOR mediated activation of eIF4A are most sensitive to eFT226. The association of eFT226 activity in RTK tumor models with mTOR pathway activation provides a means to further enrich for sensitive patient subsets during clinical development. Clinical trials with eFT226 in patients with solid tumor malignancies have initiated.
  • ternary complex formed blocks transcription selectively downregulating RTKs
  • drug binds in 5′ UTR and inhibits translation
  • RTKs activate eIF4 and are also transcribed through them so inhibition destroys this loop;  also with KRAS too
  • main antitumor activity are by an apoptotic mechanisms; refractory tumors are not sensitive to drug induced apoptosis
  • drug inhibits FGFR2 in colorectal cancer
  • drug also effective in HER2+ tumors
  • mTOR mediated eIF4 inhibited by drug
  • they get prolonged antitumor activity after washout of drug because forms this tight terniary complex

2:00 PM – 2:05 PM
– Discussion

2:05 PM – 2:15 PM
3400 – Adenosine receptor antagonists exhibit potent and selective off-target killing of FOXA1-high cancers: Steven M. Corsello, Ryan D. Spangler, Ranad Humeidi, Caitlin N. Harrington, Rohith T. Nagari, Ritu Singh, Vickie Wang, Mustafa Kocak, Jordan Rossen, Amael Madec, Nancy Dumont, Todd R. Golub. Dana-Farber Cancer Institute, Boston, MA, Broad Institute of MIT and Harvard, Cambridge, MA @corsellos

Abstract: Drugs targeting adenosine receptors were originally developed for the treatment of Parkinson’s disease and are now being tested in immuno-oncology clinical trials in combination with checkpoint inhibitors. We recently reported the killing activity of 4,518 drugs against 578 diverse cancer cell lines determined using the PRISM molecular barcoding approach. Surprisingly, three established adenosine receptor antagonists (CGS-15943, MRS-1220, and SCH-58261) showed potent and selective killing of FOXA1-high cancer cell lines without the need for immune cells. FOXA1 is a lineage-restricted transcription factor in luminal breast cancer, hepatocellular carcinoma, and prostate cancer without known small molecule inhibitors. We find that cytotoxic activity is limited to adenosine antagonists with a three-member aromatic core bound to a furan group, thus indicating a potential off-target mechanism of action. To identify genomic modulators of drug response, we performed genome-wide CRISPR/Cas9 knockout modifier screens. Killing by CGS-15943 and MRS-1220 was rescued by knockout of the aryl hydrocarbon receptor (AHR) and its nuclear partner ARNT. In confirmatory studies, knockout of AHR completely rescued killing by CGS-15943 in multiple cell types. Co-treatment with an AHR small molecule antagonist also rescued cell viability. Knockout of adenosine receptors did not alter drug response. Given that AHR is a known transcriptional regulator, we performed global mRNA sequencing to assess transcriptional changes induced by CGS-15943. The top two genes induced were the p450 enzymes CYP1A1 and CYP1B1. To determine sufficiency, we overexpressed CYP1A1 in a resistant cell line. Ectopic CYP1A1 expression sensitized to CGS-15943-mediated killing. Mass spectrometry revealed covalent trapping of a reactive metabolite by glutathione and potassium cyanide following in vitro incubation with liver microsomes. In addition, treatment of breast cancer cells with CGS-15943 for 24 hours resulted in increased γ-H2AX phosphorylation by western blot, indicative of DNA double stranded breaks. In summary, we identified off-target anti-cancer activity of multiple established adenosine receptor antagonists mediated by activation of AHR. Future studies will evaluate the functional contribution of FOXA1 and activity in vivo. Starting from a phenotypic screening hit, we leverage functional genomics to unlock the underlying mechanism of action. This project will pave the way for developing more effective therapies for biomarker-selected cancers, with potential to improve the care of patients with liver, breast, and prostate cancer.

  • developed a chemical library of over 6000 compounds (QC’d) to determine drugs that have antitumor effects
  • used a PRISM barcoded library to make cell lines to screen genotype-phenotype screens
  • for nononcology drugs fourteen drugs had activity in the PRISM assay
  • FOXA1 transcription factor high cancer cells seemed to be inhibited best with adenosine receptor inhibitor found in PRISM assay

2:15 PM – 2:20 PM
– Discussion

2:20 PM – 2:30 PM
3401 – Targeting lysosomal homeostasis in ovarian cancer through drug repurposing: Stefano Marastoni, Aleksandra Pesic, Sree Narayanan Nair, Zhu Juan Li, Ali Madani, Benjamin Haibe-Kains, Bradly G. Wouters, Anthony Joshua. University Health Network, Toronto, ON, Canada, Janssen Inc, Toronto, ON, Canada, The Kinghorn Cancer Centre, Sydney, Australia

Background: Drug repurposing has become increasingly attractive as it avoids the long processes and costs associated with drug discovery. Itraconazole (Itra) is a broad-spectrum anti-fungal agent which has an established broad spectrum of activity in human cell lines including cholesterol antagonism and inhibition of Hedgehog and mTOR pathways. Many in vitro, in vivo and clinical studies have suggested anti-proliferative activity both alone and in combination with other chemotherapeutic agents, in particular in ovarian cancer. This study is aimed at supporting the therapeutic potential of Itra and discovering and repurposing new drugs that can increase Itra anticancer activity as well as identifying new targets in the treatment of ovarian cancer.
Methods: We tested a panel of 32 ovarian cancer cell lines with different doses of Itra and identified a subset of cells which showed significant sensitivity to the drug. To identify genetic vulnerabilities and find new therapeutic targets to combine with Itra, we performed a whole genome sensitivity CRISPR screen in 2 cell lines (TOV1946 and OVCAR5) treated with non-toxic (IC10) concentrations of Itra.
Results: Pathway analysis on the top hits from both the screens showed a significant involvement of lysosomal compartments, and in particular dynamics between trans Golgi network and late endosomes/lysosomes, pathways that are affected by the autophagy inhibitor Chloroquine (CQ). We subsequently demonstrated that the combination of Itra and CQ had a synergistic effect in many ovarian cancer cell lines, even in those resistant to Itra. Further, genetic and pharmacological manipulation of autophagy indicated that upstream inhibition of autophagy is not a key mediator of the Itra/CQ mechanism of action. However, combination of Itra with other lysosomotropic agents (Concanamycin A, Bafilomycin A and Tamoxifen) displayed overlapping activity with Itra/CQ, supporting the lysosomal involvement in sensitizing cells to Itra resulted from the CRISPR screens. Analysis of lysosomal pattern and function showed a combined effect of Itra and CQ in targeting lysosomes and neutralizing their activity.
Conclusion: We identified two FDA approved drugs – CQ and Tamoxifen – that can be used in combination with Itra and exert a potent anti-tumor effect in ovarian cancer by affecting lyosomal function and suggesting a likely dependency of these cells on lysosomal biology. Further studies are in progress.

  • repurposing itraconozole in ovarian cancer potential mechanism of action is pleitropic
  • increasing doses of chloroquine caused OVCA cell death by accumulating in Golgi

2:30 PM – 2:35 PM
– Discussion

2:35 PM – 2:45 PM
3402 – BCAT1 as a druggable target in immuno-oncologyAdonia E. Papathanassiu, Francesca Lodi, Hagar Elkafrawy, Michelangelo Certo, Hong Vu, Jeong Hun Ko, Jacques Behmoaras, Claudio Mauro, Diether Lambrechts. Ergon Pharmaceuticals, Washington, DC, VIB Cancer Centre-KULeuven, Leuven, Belgium, Alexandria University, Alexandria, Egypt, University of Birmingham, Birmingham, United Kingdom, Ergon Pharmaceuticals, Washington, DC, Imperial College London, London, United Kingdom

2:45 PM – 2:50 PM
– Discussion

2:50 PM – 3:00 PM
3403 – Drugging the undruggable: Lessons learned from protein phosphatase 2A: Derek Taylor, Goutham Narla. Case Western Reserve University, Cleveland, OH, University of Michigan, Ann Arbor, MI @gouthamnarla

Abstract: Protein phosphatase 2A (PP2A) is a key tumor suppressor responsible for the dephosphorylation of many oncogenic signaling pathways. The PP2A holoenzyme is comprised of a scaffolding subunit (A), which serves as the structural platform for the catalytic subunit (C) and for an array of regulatory subunits (B) to assemble. Impairment of PP2A is essential for the pathogenesis of many diseases including cancer. In cancer, PP2A is inactivated through a variety of mechanisms including somatic mutation of the Aαsubunit. Our studies show that the most recurrent Aαmutation, P179R, results in an altered protein conformation which prevents the catalytic subunit from binding. Additionally, correcting this mutation, by expressing wild type PP2A Aαin cell lines harboring the P179R mutation, causes a reduction in tumor growth and metastasis. Given its central role in human disease pathogenesis, many strategies have been developed to therapeutically target PP2A.Our lab developed a series of small molecules activators of protein phosphatase 2A. One of our more advanced analogs in this series, DT-061, drives dephosphorylation and degradation of select pathogenic substrates of PP2A such as c-MYC in cellular and in vivo systems. Additionally, we have demonstrated the phosphomimetics of MYC that prevent PP2A mediated dephosphorylation and degradation markedly reduce the anti-tumorigenic activity of this series of PP2A activators further validating the target-substrate specificity of this approach. Specific mutations in the site of drug interaction or overexpression of the DNA tumor virus small T antigen which has been shown to specifically bind to and inactivate PP2A abrogate the in vivo activity of this small molecule series further validating the PP2A specificity of this approach. Importantly, treatment with DT-061 results in tumor growth inhibition in an array of in vivocancer models and marked regressions in combination with MEKi and PARPi.To further define the mechanism of action of this small molecule series, we have used cryo-electron microscopy (cryo-EM) to visualize directly theinteraction between DT-061 and a PP2A heterotrimeric complex. We have identified molecular interactions between DT-061 and all three PP2A subunits that prevent dissociation of the active enzyme through the marked prolongation of the kOFF of the native complex. Furthermore, we demonstrate that DT-061 specifically stabilizes the B56α-PP2A holoenzyme in a fully assembled, active state to dephosphorylate oncogenic targets such as c-MYC in both cellular and in vivo systems. This 3.6 Å structure identifies dynamic molecular interactions between the three distinct PP2A subunits and highlight the inherent mechanisms of PP2A complex assembly and disassembly in both cell free and cellular systems. Thus, our findings provide fundamental insights into PP2A complex assembly and regulation, identify a unique interfacial stabilizing mode of action for the therapeutic targeting of previously undruggable proteins, and aid in the development of phosphatase-based therapeutics tailored against disease specific phosphor-protein targets. The marriage of multidisciplinary scientific practices has allowed us to present here a previously unrecognized therapeutic strategy of complex stabilization for the activation of endogenous disease combating enzymes.

  • Reactivating PP2A; dephosphorylation of proteins (serine/threonine phosphatases); regulates multiple processes in the cell
  • SV40T has an antigen that inactivates PP2A; recurrent mutations in high grade endometrial cancers
  • P179R mutation promotes uterine tumor formation (also in a distal tubule ligation model)
  • project started in a phenotypic screen that tricyclic antidepressants could have an off target which was phosphatase activators (uncoupling GPCR from anticancer activity)
  • small T antigen block the activity of these small molecule activators;
  • acts as a molecular glue to bring the activators with a heterotrimer of phosphatases
  • so their small molecule activators effective in triple negative breast cancers;  one of targets of PP2A is MYC
  • question: have not yet seen resistance to these compounds but are currently looking at this

 

3:00 PM – 3:05 PM
– Discussion

3:05 PM – 3:15 PM
3404 – Inhibition of BCL10-MALT1 interaction to treat diffuse large B-cell lymphomaH: eejae Kang, Dong Hu, Marcelo Murai, Ahmed Mady, Bill Chen, Zaneta Nikolovska-Coleska, Linda M. McAllister-Lucas, Peter C. Lucas. University of Pittsburgh School of Medicine, Pittsburgh, PA, Merck, Kenilworth, NJ, University of Michigan School of Medicine, Ann Arbor, MI, University of Pittsburgh School of Medicine, Pittsburgh, PA, University of Michigan School of Medicine, Ann Arbor, MI, UPMC Children’s Hospital, Pittsburgh, PA

Abstract: The CARMA1/BCL10/MALT1 (CBM) signaling complex mediates antigen receptor-induced activation of NF-kB in lymphocytes to support normal adaptive immunity. As the effector protein of the complex, MALT1 exhibits two activities: protease and scaffolding activities. Gain-of-function mutations in the CARMA1 moiety or its upstream regulators trigger antigen-independent assembly of oligomeric CBM complexes, leading to constitutive activation of MALT1, unregulated NF-kB activity, and development of Activated B-Cell subtype of Diffuse Large B-Cell Lymphoma (ABC-DLBCL). Existing MALT1 inhibitors block only MALT1 protease activity, causing incomplete and unbalanced inhibition of MALT1, and have the potential for inducing autoimmune side effects. Since MALT1 is recruited to the CBM complex via its interaction with BCL10, we sought to identify inhibitors of BCL10-MALT1 interaction in order to target both the protease and scaffolding activities of MALT1 to treat ABC-DLBCL.
Our previous work suggested that an antibody-epitope-like interface governs the interaction between BCL10 and MALT1, so that a therapeutic opportunity exists for developing a small molecule inhibitor of the interaction to terminate inappropriate CBM activity. Using co-immunoprecipitation studies, a mammalian two-hybrid system, and surface plasmon resonance (SPR), we confirmed that BCL10 residues 107-119 and the tandem Ig-like domains of MALT1 are critical for this interaction. We then performed a structure-guided in silico screen of 3 million compounds, based on a computational model of the BCL10-MALT1 interaction interface, to identify compounds with potential for disrupting the interaction.
Compound 1 from the initial screening hits showed dose-responsive inhibition of BCL10-MALT1 interaction in both SPR and ELISA-based assays. Functionally, Compound 1 inhibits both MALT1 protease and scaffolding activities in Jurkat T cells, as demonstrated by its inhibition of CD3/CD28-induced RelB and N4BP1 cleavage, and inhibition of IKK phosphorylation, respectively. Compound 1 also blocks IL-2 transcription and IL-2 secretion by PMA/ionomycin-treated Jurkat T cells, as well as constitutive CBM-dependent secretion of IL-6 and IL-10 by ABC-DLBCL cells. Accordingly, Compound 1 selectively suppresses the growth of ABC-DLBCL cell lines, but does not affect the growth of MALT1-independent GCB-DLBCL cell lines.
In conclusion, we have identified an early-stage small molecule compound that inhibits the BCL10-MALT1 interaction, MALT1 protease and scaffolding activities, downstream CBM-dependent signaling, and ABC-DLBCL cell growth. Structure-guided modification of this lead compound is underway to further develop a new class of protein-protein interaction inhibitors that could provide more efficacious blockade of MALT1, while offering protection from undesirable autoimmune side effects in the treatment of this aggressive form of lymphoma.

3:15 PM – 3:20 PM
– Discussion

3:20 PM – 3:30 PM
– Closing RemarksJohn S. Lazo. University of Virginia, Charlottesville, VA

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