Gilead's Yescarta – recently acquired through its purchase of Kite Pharma -has become the second gene therapy to be approved by the US Food and Drug Administration, offering a new treatment approach for patients with certain types of large B-cell lymphoma.
CAR-T offers a new treatment approach in that it is specifically manufactured for each individual patient. During the process, T cells are drawn from a patient's blood and reprogrammed in the lab to create T cells that are genetically coded to hunt the patient's cancer cells.
The regulator is allowing use of Yescarta (axicabtagene ciloleucel) in patients who have not responded to or who have relapsed after at least two other kinds of treatment.
The decision rides on the back of safety and efficacy trials involving more than 100 adults with refractory or relapsed large B-cell lymphoma, which showed a complete remission rate after treatment with Yescarta of 51 percent.
However, the drug has been approved with a risk evaluation and mitigation strategy (REMS), as it carries a boxed warning for cytokine release syndrome (CRS) – a systemic response to the activation and proliferation of CAR-T cells causing high fever and flu-like symptoms – and for neurologic toxicities, both of which can be fatal or life-threatening.
To further evaluate the long-term safety, the FDA is also requiring the manufacturer to conduct a post-marketing observational study involving patients treated with Yescarta.
The approval “marks another milestone in the development of a whole new scientific paradigm for the treatment of serious diseases,” noted FDA commissioner Scott Gottlieb. “In just several decades, gene therapy has gone from being a promising concept to a practical solution to deadly and largely untreatable forms of cancer”.
It also demonstrates “the continued momentum of this promising new area of medicine and we’re committed to supporting and helping expedite the development of these products,” he added.
As such, the regulator intends to soon release a comprehensive policy to address how it will support the development of cell-based regenerative medicine, and also clarify how we it will apply its expedited programs to breakthrough products that use CAR-T cells and other gene therapies.
Novartis’ Kymriah (tisagenlecleucel; CTL019) was the first CAR-T therapy to win clearance in the US at the end of August, for the treatment of patients up to 25 years of age with B-cell precursor acute lymphoblastic leukaemia (ALL) that is refractory or in second or later relapse.