First gene therapy to treat deadly cancer approved in US

Washington: US drug regulators have approved a first-of-its-kind cancer therapy that involves genetically modifying a patient's own immune cells to treat the deadly disease when other treatments fail.

It is the first gene therapy available in the US, ushering in a new approach to the treatment of cancer and other serious and life-threatening diseases, the US Food and Drug Administration (FDA) said.

The therapy called Kymriah (tisagenlecleucel) by Novartis has been approved for certain paediatric and young adult patients with a form of acute lymphoblastic leukemia (ALL).

"We are entering a new frontier in medical innovation with the ability to reprogramme a patient's own cells to attack a deadly cancer," said FDA Commissioner Scott Gottlieb.

"New technologies such as gene and cell therapies hold out the potential to transform medicine and create an inflection point in our ability to treat and even cure many intractable illnesses," said Gottlieb.

Kymriah, a cell-based gene therapy, is approved in the US for the treatment of patients up to 25 years of age with B- cell precursor ALL that is refractory or in second or later relapse, FDA said.

Each dose of Kymriah is a customised treatment created using an individual patient's own T-cells, a type of white blood cell known as a lymphocyte.

The patient's T-cells are collected and sent to a manufacturing centre where they are genetically modified to include a new gene that contains a specific protein (a chimeric antigen receptor or CAR) that directs the T-cells to target and kill leukaemia cells that have a specific antigen (CD19) on the surface.

Once the cells are modified, they are infused back into the patient to kill the cancer cells.

ALL is a cancer of the bone marrow and blood, in which the body makes abnormal lymphocytes. The disease progresses quickly and is the most common childhood cancer in the US.

Kymriah is approved for use in paediatric and young adult patients with B-cell ALL and is intended for patients whose cancer has not responded to or has returned after initial treatment, which occurs in an estimated 15-20 per cent of patients.

"Kymriah is a first-of-its-kind treatment approach that fills an important unmet need for children and young adults with this serious disease," said Peter Marks, director of the FDA's Center for Biologics Evaluation and Research (CBER).

"Not only does Kymriah provide these patients with a new treatment option where very limited options existed, but a treatment option that has shown promising remission and survival rates in clinical trials," said Marks.

The safety and efficacy of Kymriah were demonstrated in one multicenter clinical trial of 63 paediatric and young adult patients with relapsed or refractory B-cell precursor ALL. The overall remission rate within three months of treatment was 83 per cent.

Treatment with Kymriah has the potential to cause severe side effects. It carries a boxed warning for cytokine release syndrome (CRS), which is a systemic response to the activation and proliferation of CAR T-cells causing high fever and flu-like symptoms, and for neurological events.

Both CRS and neurological events can be life-threatening. Other severe side effects of Kymriah include serious infections, low blood pressure (hypotension), acute kidney injury, fever, and decreased oxygen.