The purpose of this two part multicenter, randomized, double-blind, placebo-controlled, Phase III study is to evaluate the efficacy and safety of alpelisib compared to alpelisib matching-placebo in combination with trastuzumab and pertuzumab as maintenance treatment of patients with HER2-positive advanced breast cancer whose tumor harbors a PIK3CA mutation following induction therapy with a taxane in combination with trastuzumab and pertuzumab. Part 1 is the open-label, safety run-in part of the study, designed to confirm the recommended phase 3 dose (RP3D) dose of alpelisib in combination with trastuzumab and pertuzumab. Following Part 1, Part 2 will be initiated, which is the randomized, Phase III part of the study.
EPIK-B2: A Two Part, Phase III, Multicenter, Randomized (1:1), Double-blind, Placebo-controlled Study to Assess the Efficacy and Safety of Alpelisib (BYL719) in Combination With Trastuzumab and Pertuzumab as Maintenance Therapy in Patients With HER2-positive Advanced Breast Cancer With a PIK3CA Mutation
The recruitment for this study was permanently halted as of 07-Dec-2022 with the intent of ending the study early because of the evolving treatment landscape and changing paradigms for HER-2 positive BC therapy. This decision was not triggered by any new or unexpected safety findings. Participants in Part 1 will be allowed to continue study treatment (alpelisib in combination with trastuzumab and pertuzumab) if they are deriving clinical benefit as assessed by the investigator and after discussion with the participant and documentation in the medical record. All participants in Part 2 will be unblinded for knowledge of treatment allocation and continuity treatment planning.Participants in the experimental arm will be allowed to continue alpelisib in combination with trastuzumab and pertuzumab based on investigator's judgement and benefit/risk assessment.Participants in Part 2 who are still receiving study treatment in the control arm with alpelisib matching-placebo will not be allowed cross-over to the experimental arm. These participants will be allowed to continue on trastuzumab and pertuzumab if they are deriving clinical benefit as assessed by the investigator and after discussion with the participant and documentation in the medical record.