Phase II Study Evaluating Safety and Effectiveness of Inavolisib Combination Treatments for Early-Stage PIK3CA-Mutated Breast Cancer

What this Trial Is About

Researchers are evaluating the safety and effectiveness of inavolisib combination therapies in women with untreated, PIK3CA-mutated, Stage II-III estrogen receptor-positive, HER2-negative breast cancer. This Phase II, open-label study focuses on early-stage breast cancer patients who are candidates for neoadjuvant endocrine combination therapy and surgery. The trial aims to understand how well these treatments work and monitor their safety in this specific group. Participants will be assigned to one of several treatment groups receiving different combinations of inavolisib, letrozole, and ribociclib. Treatments are given orally once daily in cycles lasting 21 or 28 days. Some arms start with two drugs before adding the third, while others begin with the three-drug combination. Treatment continues through six cycles, with dosing schedules varying slightly between cycles. During the study, participants will undergo regular assessments including tumor response evaluations, Ki-67 biomarker measurements, and patient-reported outcomes about symptoms and treatment side effects. Researchers will monitor adverse events from the first dose until 30 days after the last dose, about eight months total. Participants will also have breast surgery after completing neoadjuvant treatment unless the cancer is inoperable. The study includes multiple visits for treatment and monitoring throughout the treatment period.

A Study to Test Inavolisib Treatments in Participants With Early-Stage, PIK3CA-Mutated Breast Cancer