what is car-t cell therapy?
a t-cell [so called because they develop in the thymus gland] is a type of white blood cell and it plays an important role in fighting cancer in the body, by looking for and destroying abnormal cells in the body.
t-cells can be taken out of a patient’s body and genetically modified to boost their ability to recognize and kill cancer cells. they are collected from the blood and then sent to a laboratory where they are genetically engineered to express chimeric antigen receptors [CAR] on their surface. CARs are a protein that allow t-cells to recognize targeted tumour cells. the genetically modified t-cells are expanded by growing cells in the laboratory until there are millions of them. the process of engineering and growing sufficient quantities of car t-cells can take a few days to a few weeks. these cells are then re-infused back into the patient and the new receptors enable them to recognize specific proteins on the cancer cells and kill them.
because car-t is a living therapy, they are able to circulate around the body just like any other blood cell. car-t reacts when it comes into contact with the target cancer cells. this allows the car t-cells to educate the immune system to recognize and kill cancer cells. research has shown that car t-cells can remain in the body and continue to be active for years.
this type of cancer therapy is a first in its kind and we are only just at the beginning of fully understanding how to utilize the immune system to fight off cancer. immuno-oncology has catalysed the way we think about and treat cancer and car t-cell therapy has revolutionized outcomes for blood cancer patients. but in order to fully utilize the potential of this therapy we also need to think about how the system needs to adapt and adopt as new breakthroughs and technologies will continue to disrupt our healthcare. we can’t bring these new innovations into an old framework. the appropriate and equitable implementation of car-t in canada will require that we rethink the way we do things, rethink how we fund therapies and especially how we collaborate as a community of stakeholders.
car t-cell therapies have had impressive results in patients with blood cancers- current car t-cell therapies are available for paediatric patients with acute lymphoblastic leukaemia [ALL] b-cell that is refractory or relapsed and for adult patients with relapsed or refractory diffuse large b-cell lymphoma [DLBCL].
a growing number of car t-cell therapies are being developed and tested in clinical studies for other blood cancers, including chronic lymphocytic leukemia [CLL] and multiple myeloma. research is being conducted to see if car t-cell therapies can be effective in solid tumours as well. [ more about available clinical trials ]
the canadian agency for drugs and technology in health [CADTH] reported that there will be somewhere between 30-50 new car-t therapies coming for review in the next five years in both the oncology and non-oncology space.
in september 2018, health canada approved the very first car-t cell therapy, tisagenlecleucel [kymriah] and is currently reviewing a second car-t cell therapy axicabtagene ciloleucel [yescarta] for the treatment of non-hodgkin’s lymphoma. this past january 2019, both the canadian agency for drugs and technology in health [CADTH] and the institut national d’excellence en santé et services sociaux [INESSS] published their recommendations for tisagenlecleucel, recommending that it be funded for canadian patients so long as the price is lowered and certain conditions around implementation are met.
as groundbreaking as car t-cell therapy is, it is also incredibly complex and expensive to deliver, forcing decision makers to think about how to delivery innovation into an old framework. it has also creating an opportunity for stakeholders within the cancer care continuum to work together in ways not done before. the implementation, delivery and adoption of car-t into the canadian landscape is an opportunity for canada to step up to the plate and delivery on its healthcare for everyone canadians are proud of and known for the world over.