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Posts Tagged ‘Alliance for Clinical Trials in Oncology’


NIH Considers Guidelines for CAR-T therapy: Report from Recombinant DNA Advisory Committee

Reporter: Stephen J. Williams, Ph.D.

In the mid to late 1970’s a public debate (and related hysteria) had emerged surrounding two emerging advances in recombinant DNA technology;

  1. the development of vectors useful for cloning pieces of DNA (the first vector named pBR322) and
  2. the discovery of bacterial strains useful in propagating such vectors

As discussed by D. S, Fredrickson of NIH’s Dept. of Education and Welfare in his historical review” A HISTORY OF THE RECOMBINANT DNA GUIDELINES IN THE UNITED STATES” this international concern of the biological safety issues of this new molecular biology tool led the National Institute of Health to coordinate a committee (the NIH Recombinant DNA Advisory Committee) to develop guidelines for the ethical use, safe development, and safe handling of such vectors and host bacterium. The first conversations started in 1974 and, by 1978, initial guidelines had been developed. In fact, as Dr. Fredrickson notes, public relief was voiced even by religious organizations (who had the greatest ethical concerns)

On December 16, 1978, a telegram purporting to be from the Vatican was hand delivered to the office of Joseph A. Califano, Jr., Secretary of Health, Education,

and Welfare. “Habemus regimen recombinatum,” it proclaimed, in celebration of the

end of a long struggle to revise the NIH Guidelines for Research Involving

Recombinant DNA Molecules

The overall Committee resulted in guidelines (2013 version) which assured the worldwide community that

  • organisms used in such procedures would have limited pathogenicity in humans
  • vectors would be developed in a manner which would eliminate their ability to replicate in humans and have defined antibiotic sensitivity

So great was the success and acceptance of this committee and guidelines, the NIH felt the Recombinant DNA Advisory Committee should meet regularly to discuss and develop ethical guidelines and clinical regulations concerning DNA-based therapeutics and technologies.

A PowerPoint Slideshow: Introduction to NIH OBA and the History of Recombinant DNA Oversight can be viewed at the following link:

http://www.powershow.com/view1/e1703-ZDc1Z/Introduction_to_NIH_OBA_and_the_History_of_Recombinant_DNA_Oversight_powerpoint_ppt_presentation

Please see the following link for a video discussion between Dr. Paul Berg, who pioneered DNA recombinant technology, and Dr. James Watson (Commemorating 50 Years of DNA Science):

http://media.hhmi.org/interviews/berg_watson.html

The Recombinant DNA Advisory Committee has met numerous times to discuss new DNA-based technologies and their biosafety and clinical implication including:

A recent Symposium was held in the summer of 2010 to discuss ethical and safety concerns and discuss potential clinical guidelines for use of an emerging immunotherapy technology, the Chimeric Antigen Receptor T-Cells (CART), which at that time had just been started to be used in clinical trials.

Considerations for the Clinical Application of Chimeric Antigen Receptor T Cells: Observations from a Recombinant DNA Advisory Committee Symposium Held June 15, 2010[1]

Contributors to the Symposium discussing opinions regarding CAR-T protocol design included some of the prominent members in the field including:

Drs. Hildegund C.J. Ertl, John Zaia, Steven A. Rosenberg, Carl H. June, Gianpietro Dotti, Jeffrey Kahn, Laurence J. N. Cooper, Jacqueline Corrigan-Curay, And Scott E. Strome.

The discussions from the Symposium, reported in Cancer Research[1]. were presented in three parts:

  1. Summary of the Evolution of the CAR therapy
  2. Points for Future Consideration including adverse event reporting
  3. Considerations for Design and Implementation of Trials including mitigating toxicities and risks

1. Evolution of Chimeric Antigen Receptors

Early evidence had suggested that adoptive transfer of tumor-infiltrating lymphocytes, after depletion of circulating lymphocytes, could result in a clinical response in some tumor patients however developments showed autologous T-cells (obtained from same patient) could be engineered to express tumor-associated antigens (TAA) and replace the TILS in the clinical setting.

However there were some problems noticed.

  • Problem: HLA restriction of T-cells. Solution: genetically engineer T-cells to redirect T-cell specificity to surface TAAs
  • Problem: 1st generation vectors designed to engineer T-cells to recognize surface epitopes but engineered cells had limited survival in patients.   Solution: development of 2nd generation vectors with co-stimulatory molecules such as CD28, CD19 to improve survival and proliferation in patients

A summary table of limitations of the two types of genetically-modified T-cell therapies were given and given (in modified form) below

                                                                                                Type of Gene-modified T-Cell

Limitations aβ TCR CAR
Affected by loss or decrease of HLA on tumor cells yes no
Affected by altered tumor cell antigen processing? yes no
Need to have defined tumor target antigen? no yes
Vector recombination with endogenous TCR yes no

A brief history of construction of 2nd and 3rd generation CAR-T cells given by cancer.gov:

http://www.cancer.gov/cancertopics/research-updates/2013/CAR-T-Cells

cartdiagrampic

Differences between  second- and third-generation chimeric antigen receptor T cells. (Adapted by permission from the American Association for Cancer Research: Lee, DW et al. The Future Is Now: Chimeric Antigen Receptors as New Targeted Therapies for Childhood Cancer. Clin Cancer Res; 2012;18(10); 2780–90. doi:10.1158/1078-0432.CCR-11-1920)

Constructing a CAR T Cell (from cancer.gov)

The first efforts to engineer T cells to be used as a cancer treatment began in the early 1990s. Since then, researchers have learned how to produce T cells that express chimeric antigen receptors (CARs) that recognize specific targets on cancer cells.

The T cells are genetically modified to produce these receptors. To do this, researchers use viral vectors that are stripped of their ability to cause illness but that retain the capacity to integrate into cells’ DNA to deliver the genetic material needed to produce the T-cell receptors.

The second- and third-generation CARs typically consist of a piece of monoclonal antibody, called a single-chain variable fragment (scFv), that resides on the outside of the T-cell membrane and is linked to stimulatory molecules (Co-stim 1 and Co-stim 2) inside the T cell. The scFv portion guides the cell to its target antigen. Once the T cell binds to its target antigen, the stimulatory molecules provide the necessary signals for the T cell to become fully active. In this fully active state, the T cells can more effectively proliferate and attack cancer cells.

2. Adverse Event Reporting and Protocol Considerations

The symposium had been organized mainly in response to two reported deaths of patients enrolled in a CART trial, so that clinical investigators could discuss and formulate best practices for the proper conduct and analysis of such trials. One issue raised was lack of pharmacovigilence procedures (adverse event reporting). Although no pharmacovigilence procedures (either intra or inter-institutional) were devised from meeting proceedings, it was stressed that each institution should address this issue as well as better clinical outcome reporting.

Case Report of a Serious Adverse Event Following the Administration of T Cells Transduced With a Chimeric Antigen Receptor Recognizing ERBB2[2] had reported the death of a patient on trial.

In A phase I clinical trial of adoptive transfer of folate receptor-alpha redirected autologous T cells for recurrent ovarian cancer[3] authors: Lana E Kandalaft*, Daniel J Powell and George Coukos from University of Pennsylvania recorded adverse events in pilot studies using a CART modified to recognize the folate receptor, so it appears any adverse event reporting system is at the discretion of the primary investigator.

Other protocol considerations suggested by the symposium attendants included:

  • Plan for translational clinical lab for routine blood analysis
  • Subject screening for pulmonary and cardiac events
  • Determine possibility of insertional mutagenesis
  • Informed consent
  • Analysis of non T and T-cell subsets, e.g. natural killer cells and CD*8 cells

3. Consideration for Design of Trials and Mitigating Toxicities

  • Early Toxic effectsCytokine Release Syndrome– The effectiveness of CART therapy has been manifested by release of high levels of cytokines resulting in fever and inflammatory sequelae. One such cytokine, interleukin 6, has been attributed to this side effect and investigators have successfully used an IL6 receptor antagonist, tocilizumab (Acterma™), to alleviate symptoms of cytokine release syndrome (see review Adoptive T-cell therapy: adverse events and safety switches by Siok-Keen Tey).

 

Below is a video form Dr. Renier Brentjens, M.D., Ph.D. for Memorial Sloan Kettering concerning the finding he made that the adverse event from cytokine release syndrome may be a function of the tumor cell load, and if they treat the patient with CAR-T right after salvage chemotherapy the adverse events are alleviated..

Please see video below:

http link: https://www.youtube.com/watch?v=4Gg6elUMIVE

  • Early Toxic effects – Over-activation of CAR T-cells; mitigation by dose escalation strategy (as authors in reference [3] proposed). Most trials give billions of genetically modified cells to a patient.
  • Late Toxic Effectslong-term depletion of B-cells . For example CART directing against CD19 or CD20 on B cells may deplete the normal population of CD19 or CD20 B-cells over time; possibly managed by IgG supplementation

 Please look for a Followup Post concerning “Developing a Pharmacovigilence Framework for Engineered T-Cell Therapies”

References

  1. Ertl HC, Zaia J, Rosenberg SA, June CH, Dotti G, Kahn J, Cooper LJ, Corrigan-Curay J, Strome SE: Considerations for the clinical application of chimeric antigen receptor T cells: observations from a recombinant DNA Advisory Committee Symposium held June 15, 2010. Cancer research 2011, 71(9):3175-3181.
  2. Morgan RA, Yang JC, Kitano M, Dudley ME, Laurencot CM, Rosenberg SA: Case report of a serious adverse event following the administration of T cells transduced with a chimeric antigen receptor recognizing ERBB2. Molecular therapy : the journal of the American Society of Gene Therapy 2010, 18(4):843-851.
  3. Kandalaft LE, Powell DJ, Jr., Coukos G: A phase I clinical trial of adoptive transfer of folate receptor-alpha redirected autologous T cells for recurrent ovarian cancer. Journal of translational medicine 2012, 10:157.

Other posts on this site on Immunotherapy and Cancer include

Report on Cancer Immunotherapy Market & Clinical Pipeline Insight

New Immunotherapy Could Fight a Range of Cancers

Combined anti-CTLA4 and anti-PD1 immunotherapy shows promising results against advanced melanoma

Molecular Profiling in Cancer Immunotherapy: Debraj GuhaThakurta, PhD

Pancreatic Cancer: Genetics, Genomics and Immunotherapy

$20 million Novartis deal with ‘University of Pennsylvania’ to develop Ultra-Personalized Cancer Immunotherapy

Upcoming Meetings on Cancer Immunogenetics

Tang Prize for 2014: Immunity and Cancer

ipilimumab, a Drug that blocks CTLA-4 Freeing T cells to Attack Tumors @DM Anderson Cancer Center

Juno’s approach eradicated cancer cells in 10 of 12 leukemia patients, indicating potential to transform the standard of care in oncology

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Reporter: Prabodh Kandala, PhD

Data from the first large U.S. study assessing the effectiveness of long-term “maintenance” therapy with lenalidomide for patients with multiple myeloma show that the drug significantly improves the time to progression and overall survival for patients with this often-deadly hematologic cancer. In a paper published May 10 in the New England Journal of Medicine, Roswell Park Cancer Institute (RPCI) Professor of Oncology Philip L. McCarthy, MD, and co-authors report that lenalidomide (Revlimid), following induction therapy and hematopoietic stem-cell transplant, reduced patients’ risk of disease progression to 20%, compared to 44% disease progression in the placebo arm.

Dr. McCarthy, who is also Director of RPCI’s Blood & Marrow Transplant Program, was the Principal Investigator of the study, Cancer and Leukemia Group B (CALGB) 100104, a phase III randomized, double-blind, placebo-controlled clinical trial that opened in April 2005 and enrolled patients from 47 U.S. transplant centers.

Among 460 patients aged 18 to 70 (median age 59), 321 were randomly assigned to the lenalidomide arm, and 229 to the placebo group. All participants had received prior autologous hematopoietic stem-cell transplantation and had stable (non-progressing) disease. The participants’ assignments and responses to date were unblinded in December 2009 when the primary endpoint of the study (time to disease progression) showed a statistically significant difference between the two study groups. After January 2010, 86 of 128 eligible patients crossed over from the placebo arm to the active arm.

The researchers found that the therapy extended the time to disease progression by 19 months overall, even with the majority of placebo patients without progression crossing over to lenalidomide. The treatment was fairly well-tolerated — particularly as compared to other treatments for multiple myeloma, such as thalidomide. There was more hematologic toxicity, particularly neutropenia, in the lenalidomide group. When the study data was analyzed again in October 2011, at a median follow-up of 34 months, 37% of participants receiving lenalidomide had disease progression or had died, compared to 58% of those in the placebo group.

“These findings fill a gap that existed previously in terms of data on whether maintenance therapy with lenalidomide prolongs the time to disease progression after initial therapy. We now have evidence that it does, in this and the two other lenalidomide studies that are presented in this issue of the Journal,” said Dr. McCarthy. “This shows that patients with multiple myeloma now have options for prolonging the response to initial therapy. The next steps will be trying to improve on these responses by adding new agents that may prove even more effective in combination with lenalidomide following transplant.”

A benefit in overall survival was also seen in this study. At a median follow-up of 34 months, a total of 15% of patients who received lenalidomide and 23% of the patients receiving placebo had died. “The median overall survival among patients who required therapy before 1996 was approximately 3 years. In the era of new agents and autologous hematopoietic stem-cell transplantation, the median overall survival after transplantation is close to 8 years,” Dr. McCarthy and colleagues write in the paper, “Lenalidomide after Stem-Cell Transplantation for Multiple Myeloma.”

There was an increase in second primary cancers among the lenalidomide-arm patients. When looking at both study groups, the cumulative incidence of a second primary cancer was higher among patients in the lenalidomide group than among patients in the placebo group, and the cumulative incidence of progressive disease and death were higher among patients in the placebo group than among patients in the lenalidomide group.

The team’s research was funded by a grant (NCT00114101/CCSG No. 016056) from the National Cancer Institute (NCI) and conducted by the Alliance for Clinical Trials in Oncology (formerly Cancer and Leukemia Group B, or CALGB).

“The results of CALGB 100104 ultimately show that the long-term administration of lenalidomide is feasible,” said Monica M. Bertagnolli, MD, Chief of the Division of Surgical Oncology at Brigham and Women’s Hospital, Professor of Surgery at Harvard Medical School, and Group Chair of the Alliance for Clinical Trials in Oncology. “This positive outcome brings us closer to providing better treatment for patients with multiple myeloma. Additionally, this trial demonstrates the benefits of cooperative group research where patients participating in clinical trials help lead the way to important discoveries.”

http://www.sciencedaily.com/releases/2012/05/120509175807.htm

 

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