FDA Grants Breakthrough Therapy Designation to Genentech’s Inavolisib for Advanced Hormone Receptor-Positive, HER2-Negative Breast Cancer with a PIK3CA Mutation

Genentech, a member of the Roche Group (SIX: RO, ROG; OTCQX: RHHBY), announced today that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation for inavolisib, an investigational oral therapy, in combination with palbociclib (Ibrance) and fulvestrant, for the treatment of adult patients with PIK3CA-mutated, hormone receptor-positive, human epidermal growth factor receptor 2-negative, locally advanced or metastatic breast cancer, following recurrence on or within 12 months of completing adjuvant endocrine treatment.

“We are pleased that the FDA granted Breakthrough Therapy Designation for inavolisib in recognition of the substantial clinical benefit observed with this regimen,” said Levi Garraway, M.D., Ph.D., Genentech’s chief medical officer and head of Global Product Development. “This promising inavolisib-based regimen could transform the PI3K inhibitor class, potentially becoming the standard of care for this patient population in the first-line setting.”

Breakthrough Therapy Designation is designed to accelerate the development and regulatory review of medicines intended to treat serious or life-threatening conditions where preliminary clinical evidence has indicated they may demonstrate substantial improvement over existing therapies.

The FDA’s decision is based on positive Phase III INAVO120 results, which showed the inavolisib-based regimen reduced the risk of disease worsening or death (progression-free survival) by 57% compared to palbociclib and fulvestrant alone (15.0 months vs. 7.3 months; hazard ratio [HR]=0.43, 95% CI: 0.32-0.59, p<0.0001). Overall survival (OS) data were immature at this time, but a clear positive trend has been observed (stratified HR=0.64, 95% CI: 0.43-0.97, p=0.0338 (boundary of 0.0098). Follow-up for OS will continue to the next analysis. These data reinforce the potential for this inavolisib-based regimen to benefit patients with PIK3CA-mutated locally advanced or metastatic breast cancer.

PIK3CA is one of the most commonly mutated genes in advanced or metastatic breast cancer. Despite the prevalence of PIK3CA mutations, many patients are not tested until later in their treatment journey. Early testing for PIK3CA prior to initiating first-line treatment helps clinicians make a personalized treatment decision.

Data from INAVO120 are also being submitted to other global health authorities, including the European Medicines Agency.

Inavolisib is currently being investigated in three company-sponsored Phase III clinical studies (INAVO120, INAVO121, INAVO122) in PIK3CA-mutated locally advanced or metastatic breast cancer in various combinations. We continue to evaluate potential clinical development program expansion opportunities to address patient unmet needs in various tumor types across oncology.