FDA Approves New Drug for Severe Neutropenia in Cancer Patients

The US Food and Drug Administration (FDA) has approved tbo-filgrastim, a granulocyte colony-stimulating factor that reduces the time that cancer patients with non-myeloid malignancies experience severe chemo-related neutropenia.

Tbo-filgrastim, which is administered as an injection 24 hours after the patient receives chemotherapy, is intended for use in adults with non-myeloid malignancies on a regimen that can lead to severe neutropenia or febrile neutropenia. The new drug works by stimulating the bone marrow to increase the production of neutrophils, which fight off infections.

“Supportive care products, such as tbo-filgrastim, reduce or allow for more rapid recovery from side effects of cancer treatments,” said Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, in a press release.

Tbo-filgrastim, previously known as XM02, was evaluated in a clinical study of 348 adult breast cancer patients with advanced disease who were treated with doxorubicin and docetaxel. The trial was made up of three arms-140 patients received tbo-filgrastim, 136 received filgrastim (Neupogen), and 72 patients received a placebo. Patients were randomized to treatment with daily subcutaneous injections of 5 μg/kg/day for at least 5 days and a maximum of 14 days in each cycle.

The primary endpoint was the duration of severe neutropenia in the first cycle. The study results showed that patients receiving tbo-filgrastim recovered from severe neutropenia in 1.1 days, compared with 3.8 days for those in the placebo arm. Tbo-filgrastim, which contains a related drug substance to the previously licensed biological product filgrastim, was found to be similar in efficacy.

The safety of tbo-filgrastim was evaluated in three clinical studies that included 680 adults receiving high-dose myeloablative chemotherapy. Participants of the trials had either breast cancer, lung cancer, or non-Hodgkin lymphoma. The most common adverse event associated with tbo-filgrastim was bone pain.

Tbo-filgrastim, which is manufactured by Sicor Biotech UAB (a member of Teva Corporation), was approved in an original biologics license application. The FDA has not approved the drug as a biosimilar to filgrastim.