FDA Grants Inavolisib Priority Review for Treatment of PIK3CA-Mutated Breast Cancer
The priority review of inavolisib is for treatment of patients with advanced hormone receptor-positive, HER2-negative breast cancer with a PIK3CA mutation.
The FDA has granted priority review to inavolisib (GDC-0077; Roche) in combination with palbociclib (Ibrance; Pfizer) and fulvestrant (Faslodex; AstraZeneca), accelerating accessibility to patients in need of new treatment options. The decision is based on clinical trial findings from the phase 3 INAVO120 (NCT04191499) trial, which showed the inavolisib-based regimen more than doubled progression free survival (PFS) and significantly reduced risk of worsening disease in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2 (HER2)-negative breast cancer with a PIK3CA mutation.
Inavolisib has proven to be a crucial treatment for patients with HR+ PIK3CA-mutated breast cancer after the treatment was granted breakthrough therapy designation. Image Credits: © ChenPG - adobe.stock.com
Inavolisib is an investigational, oral therapy designed to reduce the adverse effects of endocrine therapy (ET) and provide well-tolerated, durable disease control for patients with HR+, PIK3CA-mutated breast cancer. The PIK3CA mutation alters the phosphoinositide 3-kinase (PI3K) pathway, which results in resistance to standard of care ET in combination with cyclin-dependent kinase 4/6 inhibitors. The study findings have shown the ability of inavolisib to target activating PIK3CA mutations to restore the pathway and improve treatment efficacy, potentially improving health outcomes for this patient population.1
Through a randomized, double-blind, placebo-controlled study, the investigators evaluated the effectiveness of inavolisib in combination with palbociclib and fulvestrant compared to placebo plus palbociclib and fulvestrant in 325 patients. Treatment was randomly assigned to patients who received either inavolisib or a placebo. Inavolisib treatments were administered on days 1 to 28 of each 28-day cycle, and the placebo, plus oral palbociclib, on days 1 to 21 of each cycle, and intramuscular fulvestrant approximately every 4 weeks.1-3
The results showed significant reductions in PFS or death by 57% when being treated with the inavolisib-based regimen compared with palbociclib and fulvestrant alone (15.0 months vs 7.3 months; hazard ratio=.43, 95% CI: .32-.59, P<.0001). There was also an observable positive trend in overall survival (stratified HR=.64, 95% CI: .43-0.97, p=.0338), however, the study authors noted that further investigation is needed.1,2
Inavolisib has proven to be a crucial treatment for patients with HR+ PIK3CA-mutated breast cancer after the treatment was granted breakthrough therapy designation. The priority review marks significant advancements in available treatment options for patients in urgent need of care who had adverse responses to other treatments. Ongoing research and further analysis will be crucial in solidifying the role of inavolisib in the breast cancer treatment landscape and expanding access to the therapy for those who may need it.
“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 harbour PIK3CA mutations,” said Levi Garraway, MD, PhD, chief medical officer and head of global product development at Roche, in a news release. “We welcome the FDA’s priority review designation for inavolisib, which underscores the urgency to bring this potential best-in-class treatment option to patients as quickly as possible.”2
