IP trend evaluation – CAR T-cell therapy

Chimeric antigen receptor (CAR) T-cell therapy is transforming the way that cancer is treated. It is an innovative immunotherapy treatment which uses patients’ immune cells to target tumours. Chemotherapy and radiation therapy have long been the major non-invasive treatments for cancer. However, if a patient’s cancer returns even after extensive chemotherapy, curative options are limited. CAR T-cell therapy is one such option for people suffering from acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma.

IP filings in this domain have increased significantly since 2015, with the United States and China supplying the bulk of inventions. In August 2017 the US Food and Drug Administration (FDA) announced the first approval in an expected wave of novel and highly personalised therapies that target cancer and other deadly diseases in an entirely new way: by modifying patients' cells. Two CAR T-cell therapies – tisagenlecleucel (Kymriah) and axicabtagene ciloleucel (Yescarta) – have been FDA approved for treating ALL and non-Hodgkin lymphoma.

These developments and the potential efficacy of these therapies have encouraged many major pharmaceutical players into the industry – a trend which is supported by these companies’ patent filing rates and M&A activities. For example, Gilead Science recently acquired Kite Pharma and gained a leading-edge cell therapy technology and a new oncology drug (Kymriah); and Juno therapeutics acquired Abvitro for its immune sequencing method and to develop its technology.

Many new companies are investing in CAR T-cell therapy, including:

• Shanghai Unicar Therapy Bio Medicine Technology;
• Nantcell (part of Nantworks Llc); and
• Aleta Biotherapeutics.

However, despite considerable R&D in this area, its technology remains nascent and must overcome a number of challenges for its adoption as a conventional cancer therapy – for example, its many side effects, including:

• cytokine-release syndrome;
• neurologic toxicities;
• B-cell aplasia; and
• tumour lysis syndrome.

IP filings in this domain are expected to boom when companies develop successful products that mitigate these side effects.

IP landscaping has determined that CAR T-cell therapy depends on many important factors – the most important being the identification of relevant antigens, which are targeted by T cells. Filing trends and success rates support the effectiveness of the well-researched CD19 antigen for treating ALL and chronic lymphocytic leukemia (CLL).

In recent years, R&D has begun to focus on other antigens such as CD20, CD22, GD2, CD33 and mesothelin, possibly because most companies develop therapies which target additional diseases, including acute myeloid leukemia (AML) and multiple myeloma. Recent IP trends confirm that identifying antigens that are highly expressed by tumour cells, but have limited or no expression in normal cells is an important factor in developing CAR T-cell therapies.

Among the most active players in the domain are:

• Novartis;
• Cellectis;
• Juno Therapeutics; and
• Kite Pharma.

At present, only Novartis and Kite have FDA-approved CAR T-cell therapies: Kymriah and Yescarta, respectively. Technology major Cellectics has taken a different approach, using allogeneic or donor cells rather than patients’ T-cells.

As with any nascent technology, the application potential of CAR T-cell therapy remains unknown. In addition to treating diseases other than cancer, research is underway to discover whether this therapy may be used for:

• targeting multiple antigens simultaneously, thereby mitigating the off-target toxicities of CAR T-cells;
• developing off-the-shelf CAR T-cell therapies (ie, using allogeneic T-cells); and
• reducing therapy costs.