Puma Biotechnology Inc (NASDAQ: PBYI) enjoyed a strong reading on the markets Tuesday, after the company reported the FDA approval of NERLYNX (neratinib) for the extended adjuvant treatment of HER2-positive early stage breast cancer.
Puma expects neratinib to become commercially available in September and to be marketed as NERLYNX.
FDA approval was based on the Phase III ExteNET trial, a multicenter, randomized, double-blind, placebo-controlled trial of neratinib following adjuvant trastuzumab treatment. Women (n=2,840) with early-stage HER2-positive breast cancer and within two years of completing adjuvant trastuzumab were randomized to receive either neratinib or placebo for one year.
The most common adverse reactions were 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 most common adverse reaction leading to discontinuation was diarrhea, which was observed in 16.8% of neratinib-treated patients. Hepatotoxicity or increases in liver transaminases led to drug discontinuation in 1.7% of neratinib-treated patients.
Approximately 20% to 25% of breast cancer tumors over-express the HER2 protein. HER2-positive breast cancer is often more aggressive than other types of breast cancer, increasing the risk of disease progression and death. Although research has shown that trastuzumab can reduce the risk of early stage HER2-positive breast cancer returning after surgery, up to 25% of patients treated with trastuzumab experience recurrence.
Stock in Puma sprang to life, gaining $7.35, or 8.5%, to $93.45, by Tuesday’s closing bell.
