NEW YORK – The US Food and Drug Administration has accepted and granted priority review to Genentech's new drug application (NDA) seeking approval for its PI3Kα inhibitor inavolisib as a treatment in PIK3CA-mutated, hormone receptor (HR)-positive, HER2-negative breast cancer after adjuvant endocrine therapy.
On Tuesday, Genentech said its NDA contained results from the Phase III INAVO120 trial, which demonstrated that patients receiving a regimen comprising inavolisib, Pfizer's CDK4/6 inhibitor Ibrance (palbociclib), and fulvestrant had a median progression-free survival of 15 months compared to 7.3 months for those on just Ibrance and fulvestrant. Overall survival results were not mature at the time of the analysis but showed a trend favoring the inavolisib combination.
"The addition of inavolisib to standard of care treatment significantly delayed disease progression in the first-line setting and has the potential to extend survival for people with metastatic breast cancers that harbor PIK3CA mutations," Levi Garraway, chief medical officer and head of global product development at Genentech, said in a statement.
Approximately 40 percent of HR-positive metastatic breast cancers have a PIK3CA mutation. Currently, Novartis' Piqray (alpelisib) is the only PI3Kα inhibitor approved in this setting. Genentech, a Roche subsidiary, is one of a handful of companies hoping to challenge Piqray's market position by developing a mutant PI3Kα inhibitor with a more favorable safety profile, particularly with respect to hyperglycemia, a common side effect that limits the use of these drugs.
The FDA expects to decide on Genentech's inavolisib NDA by Nov. 27. Genentech is submitting data from the INAVO120 trial to other global health authorities, including the European Medicines Agency.