FDA approves treatment for severe neutropenia in cancer patients

Issue: September 25, 2012

The FDA today approved a product designed to reduce severe neutropenia in cancer patients who undergo chemotherapy.

Perspective from Maryam B. Lustberg, MD, MPH

Tbo-filgrastim (Sicor Biotech) is approved for use in adults who malignancies other than blood or bone marrow cancers.

Chemotherapy drugs often cause neutropenia, a significant decrease in the production of infection-fighting white blood cells called neutrophils. The condition can increase risk for fever or infection.

Tbo-filgrastim — which is administered via injection starting 24 hours after chemotherapy — stimulates the bone marrow to increase production of neutrophils, according to an FDA press release.

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

The FDA based its approval on results of a study in which 348 adults with advanced breast cancer received treatment with the chemotherapy drugs docetaxel and doxorubicin.

Researchers randomly assigned the patients to receive tbo-filgrastim, a placebo or a non-approved product that also stimulates bone marrow to increase neutrophil production.

Patients assigned to tbo-filgrastim recovered from severe neutropenia within 1.1 days, compared with 3.8 days for patients who were assigned to placebo, according to the FDA release.

The FDA evaluated tbo-filgrastim’s safety based on results of three studies that included a combined 680 adults with breast cancer, lung cancer or non-Hodgkin’s lymphoma. All patients received high-dose chemotherapy, which reduced bone marrow cells.

In those studies, the most common side effect reported by patients who received tbo-filgrastim was bone pain, according to the FDA.

Perspective

Maryam B. Lustberg, MD, MPH

Patients receiving certain types of chemotherapy regimens are at risk for neutropenia, or a low number of neutrophils. Neutrophils are white blood cells that are the body’s main defense against infections by fighting bacteria in the blood. Patients with neutropenia are at risk of infections that may become life threatening. Neutropenia also can cause delays in chemotherapy administration or reduce dose intensity of a given regimen. A therapy that shortens the duration and severity of neutropenia can potentially reduce incidence of febrile neutropenia, and can lead to reduction of life-threatening infections and hospitalizations. It also can help reduce dose delays in chemotherapy schedules due to neutropenia.

Granulocyte colony-stimulating factor (G-CSF) is a naturally occurring hormone that stimulates production of neutrophils. A recombinant form of G-CSF is used to treat cancer patients with neutropenia in order to stimulate the bone marrow to produce neutrophils. Tbo-filgrastrim is one such drug that is a short-acting injection to stimulate the bone marrow to increase neutrophil production. Tbo-filgrastim joins two other FDA-approved GSCF stimulating agents, filgrastim and peg-filgrastim, that are currently on the market. All of these agents serve to shorten period of neutropenia during chemotherapy and help reduce delays in chemotherapy administration. All have similar toxicity of bone pain after injection.

Maryam B. Lustberg, MD, MPH

Breast medical oncologist

The Ohio State University Comprehensive Cancer Center — Arthur G. James Cancer Hospital and Richard J. Solove Research Institute

Disclosures: Dr. Lustberg reports no relevant financial disclosures.