The FDA recently approved Sicor Biotech’s tbo-filgrastim (Neutroval) to reduce the time certain patients receiving chemotherapy experience severe neutropenia.
The new drug is a short-acting recombinant granulocyte colony-stimulating factor (G-CSF) agent. It is marketed as Tevagrastim in Europe, where tbo-filgrastim is classified as biosimilar to Amgen’s G-CSF product, Neupogen. Tbo-filgrastim was approved in the United States through the standard process for new drugs and some biological agents. The biosimilar approval process has yet to be finalized by FDA.
Tbo-filgrastim is intended for use in adults who have nonmyeloid malignancies and are taking chemotherapy drugs that cause a substantial decrease in the production of neutrophils in the bone marrow. This reduction in neutrophils may lead to febrile neutropenia.
Tbo-filgrastim stimulates the bone marrow to increase the production of neutrophils. It is administered as an injection beginning 24 hours after chemotherapy treatment.
“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.
Study Design
Tbo-filgrastim was evaluated in a clinical study of 348 adult patients with advanced breast cancer receiving treatment with doxorubicin and docetaxel. Patients were randomly assigned to receive tbo-filgrastim, a placebo, or a non–U.S.-approved filgrastim product, a drug that also stimulates neutrophil production by the bone marrow. The effectiveness of tbo-filgrastim was determined based on study results that showed that patients receiving tbo-filgrastim recovered from severe neutropenia in 1.1 days compared with 3.8 days in those receiving the placebo.
Tbo-filgrastim’s safety was evaluated in three clinical studies composed of 680 adults with breast cancer, lung cancer, or non-Hodgkin lymphoma who received high-dose myeloablative chemotherapy. The most common side effect observed in those receiving tbo-filgrastim was bone pain.
The manufacturer, Teva Pharmaceuticals, Ltd, announced that it does not expect to market tbo-filgrastim until November 2013 at the earliest. ■
