Prophylactic Breast Cancer Drug Receives FDA Nod

Yesterday, the FDA approved neratinib (Nerlynx) for the extended adjuvant treatment of patients with early HER2-positive breast cancer. The newly-approved kinase inhibitor is indicated to follow therapy with trastuzumab (Herceptin), according to a press release.

The approval was based on the ExteNET clinical trial, which included 2840 women with early-stage HER2-positive breast cancer who were treated with adjuvant trastuzumab within the previous 2 years. Patients were randomized to receive neratinib (n=1420) or placebo (n=1420) for 1 year.

The primary efficacy outcome was invasive disease-free survival (iDFS), which is the time between baseline to the first occurrence of invasive recurrence, distant recurrence, or death within 2 years and 28 days of follow-up, according to the FDA.

At 2 years, the investigators found that iDFS was 94.2% in patients treated with neratinib compared with 91.9% in patients treated with placebo, according to the study.

Common adverse reactions included diarrhea, nausea, abdominal pain, fatigue, vomiting, rash, stomatitis, decreased appetite, muscle spasms, dyspepsia, AST or ALT increase, nail disorder, dry skin, abdominal distention, weight loss, and urinary tract infection, the FDA reported.

Approximately 16.8% of patients treated with neratinib discontinued treatment due to diarrhea, while hepatotoxicity or increases in liver transaminases led to discontinuation in only 1.7% of the patients. The FDA advises that patients who experience these adverse events stop treatment.

The FDA approved nertanib 240 mg once daily with food for 1 year. Antidiarrheal prophylaxis should be started with the first dose and continued during the first 2 cycles of treatment, but can be taken as needed, according to the release.

Breast cancer is the most common form of the disease, with more than 250,000 women receiving a diagnosis each year, according to the National Cancer Institute. Approximately 15% of patients have HER2-positive disease.

“HER2-positive breast cancers are aggressive tumors and can spread to other parts of the body, making adjuvant therapy an important part of the treatment plan,” said Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Now, these patients have an option after initial treatment that may help keep the cancer from coming back.”