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Archive for the ‘ISO 14155’ Category

Imaging-guided cancer treatment


Imaging-guided cancer treatment

Writer & reporter: Dror Nir, PhD

It is estimated that the medical imaging market will exceed $30 billion in 2014 (FierceMedicalImaging). To put this amount in perspective; the global pharmaceutical market size for the same year is expected to be ~$1 trillion (IMS) while the global health care spending as a percentage of Gross Domestic Product (GDP) will average 10.5% globally in 2014 (Deloitte); it will reach ~$3 trillion in the USA.

Recent technology-advances, mainly miniaturization and improvement in electronic-processing components is driving increased introduction of innovative medical-imaging devices into critical nodes of major-diseases’ management pathways. Consequently, in contrast to it’s very small contribution to global health costs, medical imaging bears outstanding potential to reduce the future growth in spending on major segments in this market mainly: Drugs development and regulation (e.g. companion diagnostics and imaging surrogate markers); Disease management (e.g. non-invasive diagnosis, guided treatment and non-invasive follow-ups); and Monitoring aging-population (e.g. Imaging-based domestic sensors).

In; The Role of Medical Imaging in Personalized Medicine I discussed in length the role medical imaging assumes in drugs development.  Integrating imaging into drug development processes, specifically at the early stages of drug discovery, as well as for monitoring drug delivery and the response of targeted processes to the therapy is a growing trend. A nice (and short) review highlighting the processes, opportunities, and challenges of medical imaging in new drug development is: Medical imaging in new drug clinical development.

The following is dedicated to the role of imaging in guiding treatment.

Precise treatment is a major pillar of modern medicine. An important aspect to enable accurate administration of treatment is complementing the accurate identification of the organ location that needs to be treated with a system and methods that ensure application of treatment only, or mainly to, that location. Imaging is off-course, a major component in such composite systems. Amongst the available solution, functional-imaging modalities are gaining traction. Specifically, molecular imaging (e.g. PET, MRS) allows the visual representation, characterization, and quantification of biological processes at the cellular and subcellular levels within intact living organisms. In oncology, it can be used to depict the abnormal molecules as well as the aberrant interactions of altered molecules on which cancers depend. Being able to detect such fundamental finger-prints of cancer is key to improved matching between drugs-based treatment and disease. Moreover, imaging-based quantified monitoring of changes in tumor metabolism and its microenvironment could provide real-time non-invasive tool to predict the evolution and progression of primary tumors, as well as the development of tumor metastases.

A recent review-paper: Image-guided interventional therapy for cancer with radiotherapeutic nanoparticles nicely illustrates the role of imaging in treatment guidance through a comprehensive discussion of; Image-guided radiotherapeutic using intravenous nanoparticles for the delivery of localized radiation to solid cancer tumors.

 Graphical abstract

 Abstract

One of the major limitations of current cancer therapy is the inability to deliver tumoricidal agents throughout the entire tumor mass using traditional intravenous administration. Nanoparticles carrying beta-emitting therapeutic radionuclides [DN: radioactive isotops that emits electrons as part of the decay process a list of β-emitting radionuclides used in radiotherapeutic nanoparticle preparation is given in table1 of this paper.) that are delivered using advanced image-guidance have significant potential to improve solid tumor therapy. The use of image-guidance in combination with nanoparticle carriers can improve the delivery of localized radiation to tumors. Nanoparticles labeled with certain beta-emitting radionuclides are intrinsically theranostic agents that can provide information regarding distribution and regional dosimetry within the tumor and the body. Image-guided thermal therapy results in increased uptake of intravenous nanoparticles within tumors, improving therapy. In addition, nanoparticles are ideal carriers for direct intratumoral infusion of beta-emitting radionuclides by convection enhanced delivery, permitting the delivery of localized therapeutic radiation without the requirement of the radionuclide exiting from the nanoparticle. With this approach, very high doses of radiation can be delivered to solid tumors while sparing normal organs. Recent technological developments in image-guidance, convection enhanced delivery and newly developed nanoparticles carrying beta-emitting radionuclides will be reviewed. Examples will be shown describing how this new approach has promise for the treatment of brain, head and neck, and other types of solid tumors.

The challenges this review discusses

  • intravenously administered drugs are inhibited in their intratumoral penetration by high interstitial pressures which prevent diffusion of drugs from the blood circulation into the tumor tissue [1–5].
  • relatively rapid clearance of intravenously administered drugs from the blood circulation by kidneys and liver.
  • drugs that do reach the solid tumor by diffusion are inhomogeneously distributed at the micro-scale – This cannot be overcome by simply administering larger systemic doses as toxicity to normal organs is generally the dose limiting factor.
  • even nanoparticulate drugs have poor penetration from the vascular compartment into the tumor and the nanoparticles that do penetrate are most often heterogeneously distributed

How imaging could mitigate the above mentioned challenges

  • The inclusion of an imaging probe during drug development can aid in determining the clearance kinetics and tissue distribution of the drug non-invasively. Such probe can also be used to determine the likelihood of the drug reaching the tumor and to what extent.

Note: Drugs that have increased accumulation within the targeted site are likely to be more effective as compared with others. In that respect, Nanoparticle-based drugs have an additional advantage over free drugs with their potential to be multifunctional carriers capable of carrying both therapeutic and diagnostic imaging probes (theranostic) in the same nanocarrier. These multifunctional nanoparticles can serve as theranostic agents and facilitate personalized treatment planning.

  • Imaging can also be used for localization of the tumor to improve the placement of a catheter or external device within tumors to cause cell death through thermal ablation or oxidative stress secondary to reactive oxygen species.

See the example of Vintfolide in The Role of Medical Imaging in Personalized Medicine

vinta

Note: Image guided thermal ablation methods include radiofrequency (RF) ablation, microwave ablation or high intensity focused ultrasound (HIFU). Photodynamic therapy methods using external light devices to activate photosensitizing agents can also be used to treat superficial tumors or deeper tumors when used with endoscopic catheters.

  • Quality control during and post treatment

For example: The use of high intensity focused ultrasound (HIFU) combined with nanoparticle therapeutics: HIFU is applied to improve drug delivery and to trigger drug release from nanoparticles. Gas-bubbles are playing the role of the drug’s nano-carrier. These are used both to increase the drug transport into the cell and as ultrasound-imaging contrast material. The ultrasound is also used for processes of drug-release and ablation.

 HIFU

Additional example; Multifunctional nanoparticles for tracking CED (convection enhanced delivery)  distribution within tumors: Nanoparticle that could serve as a carrier not only for the therapeutic radionuclides but simultaneously also for a therapeutic drug and 4 different types of imaging contrast agents including an MRI contrast agent, PET and SPECT nuclear diagnostic imaging agents and optical contrast agents as shown below. The ability to perform multiple types of imaging on the same nanoparticles will allow studies investigating the distribution and retention of nanoparticles initially in vivo using non-invasive imaging and later at the histological level using optical imaging.

 multi

Conclusions

Image-guided radiotherapeutic nanoparticles have significant potential for solid tumor cancer therapy. The current success of this therapy in animals is most likely due to the improved accumulation, retention and dispersion of nanoparticles within solid tumor following image-guided therapies as well as the micro-field of the β-particle which reduces the requirement of perfectly homogeneous tumor coverage. It is also possible that the intratumoral distribution of nanoparticles may benefit from their uptake by intratumoral macrophages although more research is required to determine the importance of this aspect of intratumoral radionuclide nanoparticle therapy. This new approach to cancer therapy is a fertile ground for many new technological developments as well as for new understandings in the basic biology of cancer therapy. The clinical success of this approach will depend on progress in many areas of interdisciplinary research including imaging technology, nanoparticle technology, computer and robot assisted image-guided application of therapies, radiation physics and oncology. Close collaboration of a wide variety of scientists and physicians including chemists, nanotechnologists, drug delivery experts, radiation physicists, robotics and software experts, toxicologists, surgeons, imaging physicians, and oncologists will best facilitate the implementation of this novel approach to the treatment of cancer in the clinical environment. Image-guided nanoparticle therapies including those with β-emission radionuclide nanoparticles have excellent promise to significantly impact clinical cancer therapy and advance the field of drug delivery.

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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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Reverse Medical Corporation, a privately held medical device company focused on expanding the management of vascular disease acquired by Covidien

Reporter: Aviva Lev-Ari, PhD, RN

 

Covidien Acquires Reverse Medical Corporation

Fri, 08/22/2014 – 9:12am

Business Wire

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Generates Opportunity to Leverage Existing Vascular Technologies and Customer Relationships to Drive Increased Market Penetration

Covidien plc has announced it has acquired Reverse Medical Corporation, a privately held medical device company focused on expanding the management of vascular disease. Financial terms of the transaction were not disclosed.

“Covidien is focused on technologies that deliver improved patient care through clinically relevant and economically valuable solutions,” said Brett Wall, president, Neurovascular, Covidien. “The acquisition of Reverse Medical is complementary to our existing portfolio and will allow us to leverage existing vascular technologies to compete in the worldwide vascular embolization market, which is growing at a double digit rate.”

Covidien will report the Reverse Medical business as part of its Neurovascular product line in the Medical Devices segment. Annualized dilution is not expected to be material.

Reverse Medical is currently commercializing its vascular embolization plugs, MVP Micro Vascular Plug System and UNO™ Neurovascular Embolization System. MVP and UNO are self-expanding vessel occlusion devices, which close blood vessels for vascular embolization. A number of clinical applications require occlusion of the vasculature to rapidly, effectively and safely provide blood flow cessation.

Other Reverse Medical products include ReVerse Microcatheter for device delivery and Barrel™ Vascular Reconstruction Device (VRD), a self-expandable bifurcation aneurysm bridging device. All the devices have received CE Mark approval and are commercially available in Europe. Additionally, MVP-3 and MVP-5 are 510(k) cleared in the U.S.

 SOURCE

http://www.mdtmag.com/news/2014/08/covidien-acquires-reverse-medical-corporation?et_cid=4113388&et_rid=461755519&type=cta

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