T-Cell Immunotherapies: A New Paradigm in Cancer Treatment

 Cancer is one of the leading causes of mortality, accounting for 0.6 million deaths in 2021, in the US alone. As per the International Agency for Research on Cancer (IARC), by 2040, there are likely to be 27.5 million new cases and 16.3 million deaths related to cancer, annually. Although cancer therapeutics continue to be one of the most active areas, in terms of drug development, there is still a significant unmet need in this domain.

In fact, conventional cancer treatments, such as chemotherapy, surgery and radiation therapy, have demonstrated very limited efficacy in late-stage cancers. Specifically, chemotherapy and radiation therapy are also associated with several side effects. In addition, their non-specific nature can have severe and detrimental effects on a patient’s quality of life. Cancer immunotherapy is currently classified among the four pillars of modern cancer therapies as given below:

Amidst the current initiatives to develop more targeted anti-cancer therapies, T-cell immunotherapy has emerged as a highly potent option to selectively eliminate tumor cells with minimal side effects. Global Cart T-cell immunotherapies essentially make use of the body’s own immune system, or its components, to fight cancer. Overall, this highly specific and promising form of T-cell therapy treatment, which harnesses the versatile effector machinery of the human immune system, has revolutionized cancer treatment, globally.

Given the consistent increase in the number of cell therapies being developed and launched, this upcoming therapeutic segment is on its way to becoming one of the highest valued markets within the biopharmaceutical industry.

A number of chimeric antigen receptor T-cell (CAR-T) therapies have so far been evaluated and approved for several hematological malignancies, including KYMRIAH® (Novartis), YESCARTA® (Gilead Sciences), TECARTUS™ (Gilead Sciences), Breyanzi® (Bristol Myers Squibb), Abecma™ (Bristol Myers Squibb) and CARVYKTI™ (Janssen Biotech / Legend Biotech). It is worth mentioning that, recently, KIMMTRAK® (Immunocore) became the first T-cell receptor (TCR) therapy to receive approval from the USFDA.

Advances in molecular research and genetic manipulation techniques have led to the development of several platforms that can be used to harness the underlying potentials of T-cells and direct their functionality to offer therapeutic benefit. Various strategies that are used to redirect T-cells in order to elicit the desired immune response are given below:

The process of T-cell therapy manufacturing begins with the collection of leukocytes from the patient’s blood by leukapheresis. The collected leukocytes are further enriched by using counterflow centrifugal elutriation or subsets selection. The genetic information of the enriched leukocytes is then manipulated by culturing them with bead-based artificial APCs, followed by addition of viral vectors.

For several days, the culture is expanded in the bioreactor. Post amplification engineered T-cells are washed and concentrated. Samples are taken from this bulk product to conduct quality control testing. The final product is cryopreserved and is shipped to distant infusion sites, where the product bag is thawed and infused back to the patient. Generally, production of T-cell therapies takes 5 to 10 days. The general process of manufacturing T-cell therapies illustrated is given below:

Conclusion:

Over the past few years, T-cell immunotherapy has been successful in carving out a significant niche in the pharmaceutical market. A number of such targeted therapies have already been approved whilst a robust development pipeline indicates that the T-cell immunotherapy market is likely to grow at a steady pace in the foreseen future.

Moreover, the ongoing research activity in this field has led to the discovery of several novel molecular targets, further strengthening the research pipelines of companies engaged in this market. Currently, several industry and non-industry players are focused on the development of technologies that are capable of overcoming the existing roadblocks in the production / adoption of T-cell therapies.

Driven by the availability of innovative technology platforms, lucrative funding and encouraging clinical trial results, the T-cell immunotherapies market is poised to grow in the long-run, as multiple product candidates are expected to receive marketing approval in the coming decade.