Tuesday, September 22, 2015

Cell-based immunotherapy: Will the new “magic bullets” against cancer reach the patients?

By Fabio D'Agostino

Over the last four years we have witnessed an increasing number of promising studies and clinical trials aimed to harness the innate potential of T-cells to fight cancer. These cells can be engineered to get around the natural protection mechanisms and target tumour cells either via a chimeric antigen receptor (CAR) or by affinity-enhanced T-cell receptor (TCR).The former have proven to be more effective for haematological malignancies as they can mainly target antigen on the cell surface. The latter have the potential to target also intracellular antigens and this makes them, potentially, a more suitable candidate for solid tumours. Other than Novartis, which is developing a CAR-T cell therapy (known as CTL019) with an exclusive agreement with the University of Pennsylvania, successful companies in this field include Bluebird Bio, Juno Therapeutics and Kite Pharma. Adaptimmune, which partnered with GSK last year, is, on the other hand, more focused on TCR based therapies for a number of solid tumours. Unfortunately, as target antigens are also expressed by heathy cells in vital organs, the risk of potentially lethal side effects is not negligible. While research groups try to create low-affinity CAR-T cells or other approach to reduce side effects, developers and investors wonder:

Will the industry be able to deliver and cope with the manufacturing demand?

Although one might argue that promising clinical data are the real drive, these new “living drugs” might not even reach the patients on large scale if they come with an astronomical price tag and investors might walk away from a technology that requires huge investment to be made commercially viable. Moreover, in the optimistic scenario where all the T-cell based immunotherapies currently in development will prove clinical effective, only who managed to engineer down costs, while maintain safety and effectiveness, will win the race. As T-based immunotherapies are mainly patient-specific drugs, where 1 batch is equal to 1 patient, manufacturing costs are currently very high. Other than cost-effectiveness, there are also a number of challenges which still need to be overcome, as shown in the following diagram.

An increasing number of companies worldwide are betting on closed and automated system to tackle many of these challenges. Dr Andrew Kaiser shared his vision in a recent paper1. He explains how a “device-based manufacturing” could enable to scale out production of patient specific cellular products while considerably reducing costs in terms of labour and facility. Devices like the CliniMACS Prodigy (Miltenyi Biotec), which are capable of performing automatically all steps of a conventional manufacturing process for gene-modified T-cell product, could be run in a room where an operator could oversee several units at the same time. Another interesting platform is the one developed by Octane (Canada). Octane’s automation platform consists of Cocoon, which acts as the control system, and a disposable pre-sterilized cassette, where the cell manipulations occur. Each cassette can be easily customized to the unit operations of the manufacturing process. As the process parameters are monitored and controlled, each Cocoon is able to react accordingly to sensors’ feedback to accommodate natural variation in starting cellular material from each patient. Lonza recently announced an exclusive technology evaluation of the Octane Cocoon™ cell production platform with the goal of a global deployment of this groundbreaking innovation. Dr Nuala Trainor (Director of Biological Programs at Octane Medical Group) explained how their “GMP-in-a-box” production system could solve many of the issues linked to the manufacturing of patient-specific cell-products by enabling production within the clinical facility. She even envisions a “franchising model” where the manufacturer of the automation system would be responsible for providing all elements of support required for routine implementation and all operational supplies2.

                Will automated manufacturing directly in the clinical facility be really the answer?

According to Dr Robert Preti (President of PCT and CSO at Neostem), the only way to successfully achieve scalability and sustainability for patient specific cell therapies at commercial scale is an industry-wide effort of innovation and engineering to rebuilt unit operations and move processes from a cleanroom focus towards production spaces more suited to “high-volume” production3. Perhaps this will drive the development of the new system for commercial-scale manufacturing that Neostem aims to develop with Invetech.  The push towards new facility design for cell therapy products at commercial stage is also echoed by GE Healthcare which is working towards a closed, digitally integrated, automated ecosystem capable of manufacturing patient-specific cell therapy products and distribute them worldwide in a regulatory complainant manner. New generation GMP facilities will have to be designed.

                How will a Future Factory for commercial cell-based products manufacturing look like?

In the meantime, CDMOs worldwide continue to increase their capacity to cope with the increasing manufacturing demand. Examples are Wuxi App Tec (US), MEDINET (Japan), Nikon (Japan), PharmaBIO (Japan). While automated platforms might be developed by customizing and importing technology already available; more knowledge of the “living” drug product is needed to develop analytics, potency assays and release testing for T-cell based therapies.  There is also who, to the troubles that come with patient-specific products, prefers striving to develop a universal “off-the-shelf” T-cells therapy where the cells are modified to avoid immune rejection in the recipient patient. It is the French company Cellectis which announced a strategic alliance with MD Anderson Cancer Center on clinical development of their allogeneic CART cell therapies.

After the clinical wave, a manufacturing wave of promising enabling technologies might be on its way for cell-based immunotherapy.

Fabio D’Agostino is a passionate life sciences professional with experience in both the medical device and biopharmaceutical industry. An active member of the PDA Cell and Gene Task Force, he has contributed to a number of conferences in the cell and gene therapy industries. He was also instrumental in the launch of the new journal: Cell and Gene Therapy Insights.
After graduating with Honours from the Polytechnic University of Turin (Italy) with a BSc and a Master’s in Biomedical Engineering, he started his career at LivaNova (formerly Sorin Group) before moving to Newcastle University to take an Engineering Doctorate in Biopharmaceutical Process Development. He currently holds a research position at the Institute of Genetic Medicine (Newcastle University) where he is responsible for the development of an innovative platform for modular tissue engineering.


References


[1] “Towards a commercial process for the manufacture of genetically modified T cells for therapy”, A D Kaiser, M Assenmacher, B Schröder, M Meyer, R Orentas, U Bethke and B Dropulic. Cancer Gene Therapy (2015) 22, 72–78

[2] “Rethinking clinical delivery of adult stem cell therapies”, Nuala Trainor, Alexis Pietak, Tim Smith, Nature Biotechnology 32, 729–735 (2014)            

[3] “Guest Commentary: Building a problem or a solution?”,Robert Preti, DDNews , September 2015, VOL. 11, NO. 9



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