• Phase III (INAVO120) results show that inavolisib in combination with palbociclib and fulvestrant significantly improved progression-free survival in the first-line setting
• PIK3CA mutations, found in approximately 40% of HR-positive breast cancers, are linked to tumour growth, disease progression, and treatment resistance^1,2
• Data will be shared with health authorities and presented at an upcoming medical meeting

The study met its primary endpoint of progression-free survival (PFS), demonstrating a statistically significant and clinically meaningful improvement compared to palbociclib and fulvestrant alone. Overall survival data were immature at this time, but a clear positive trend has been observed. Follow-up will continue to the next analysis.

"These pivotal study results for this inavolisib combination could represent a transformative medical advance for people with PIK3CA-mutated HR-positive breast cancer," said Levi Garraway, M.D., Ph.D., Roche’s Chief Medical Officer and Head of Global Product Development. "We look forward to expanding our portfolio of breast cancer medicines into the HR-positive space and bringing this potentially best-in-class new treatment option to patients as quickly as possible."

The inavolisib combination was well tolerated and adverse events were consistent with the known safety profiles of the individual study treatments, with no new safety signals observed.

Inavolisib is an oral therapy with high in vitro potency and selectivity for PI3Kα inhibition and the ability to specifically trigger the breakdown of mutant PI3Kα protein. With this unique dual mechanism of action, inavolisib may provide well-tolerated, durable disease control and potentially improved outcomes for people with HR-positive/HER2-negative, PIK3CA-mutated advanced breast cancer. PIK3CA mutations can lead to mutated PI3Kα protein which contributes to uncontrolled tumour growth, disease progression and resistance to endocrine-based treatment.^3,4

Inavolisib is currently being investigated in three Phase III clinical studies in people with PIK3CA-mutated metastatic breast cancer (INAVO120, INAVO121, INAVO122) in various combinations.