Puma Biotech files for approval of neratinib in USA

Shares of Puma Biotechnology (NYSE: PBYI) were up 21.7% at $34.52 in extended trading on Thursday, following the release of encouraging interim five-year invasive disease free survival results from the company's Phase III trial of PB272 (neratinib) and the announcement of a regulatory filing.

Puma said it has submitted a New Drug Application to the US Food and Drug Administration for its lead product candidate neratinib for the extended adjuvant treatment of patients with early stage HER2-overexpressed/amplified breast cancer who have received prior adjuvant trastuzumab (Herceptin)-based therapy. Last month, Puma filed for approval of neratinib with the European Medicines Agency.

“We are very pleased to announce this important regulatory milestone,” said Alan Auerbach, chief executive and President of Puma. “Although the use of trastuzumab in the adjuvant setting has led to a reduction in disease recurrence in patients with early stage HER2-positive breast cancer, there remains an unmet clinical need to further reduce the risk of recurrence and improve outcome following trastuzumab therapy. We believe that neratinib may be able to provide this type of improvement to further help patients with this disease. We look forward to working with the FDA during their review of this submission,” he added.

The submission is supported by the results of the ExteNET Phase III study, in which treatment with neratinib resulted in a 33% reduction of risk of invasive disease recurrence or death versus placebo (hazard ratio = 0.67, p = 0.009). The two-year invasive disease free survival (DFS) rate for the neratinib arm was 93.9% and the two-year invasive DFS rate for the placebo arm was 91.6%. For the pre-defined subgroup of patients with hormone receptor positive disease, the results of the trial demonstrated that treatment with neratinib resulted in a 49% reduction of risk of invasive disease recurrence or death versus placebo (hazard ratio = 0.51, p = 0.001). For the patients with hormone receptor positive disease, the two-year invasive DFS rate for the neratinib arm was 95.4% and the two-year invasive DFS rate for the placebo arm was 91.2%.