PIKALO-2
Research type
Research Study
Full title
A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study of Tersolisib Combined with a CDK4/6 Inhibitor and Endocrine Therapy in Adults with HR+, HER2- Advanced Breast Cancer with a PIK3CA Mutation Who Received No Prior Treatment for Advanced Breast Cancer (PIKALO-2)
IRAS ID
1013063
Contact name
Maire O'Sullivan
Contact email
Sponsor organisation
Eli Lilly and Company
Clinicaltrials.gov Identifier
Research summary
J6M-MC-JSGD will evaluate the safety and effectiveness of a medicine called LY4064809 given in combination with current treatments for untreated HR+, HER2- advanced breast cancer with a PIK3CA mutation.
The current preferred treatment for hormone receptor-positive (HR+) / human epidermal growth factor receptor 2-negative (HER2-) breast cancer involves endocrine therapy (ET) in combination with a CDK4/6 inhibitor. Endocrine therapy (also known as hormone therapy) works by lowering or blocking hormones that can stimulate breast cancer cells. CDK4/6 inhibitors are drugs that stop breast cancer cells from multiplying.
The PIK3CA gene plays an important role in how cells grow and survive. In many people with HR+ / HER2- breast cancer, this gene has changed (mutated). This change negatively affects a protein called PI3K, contributing to cancer growth. Current medicines that block the PI3K protein have common side effects as they affect healthy cells as well as cancer cells. This limits their use and effectiveness.
The study medicine, LY4064809, appears to work by targeting cancer cells only. This could lead to less side effects and more effective use in combination with other breast cancer treatments.
There are 2 parts to this study:
Part 1 will find the best dose of LY4064809 to give. In this part of the study, participants will be randomly assigned in a 1:1 ratio to receive 1 of 2 dose levels of LY4064809 combined with ET (aromatase inhibitors or fulvestrant) and a CDK4/6 inhibitor (ribociclib, palbociclib, or abemaciclib). Part 2 will compare the effectiveness and safety of LY4064809 against placebo. Study participants will be randomly assigned in a 1:1 ratio to receive either LY4064809 combined with ET (aromatase inhibitors or fulvestrant) and a CDK4/6 ribociclib, palbociclib, or abemaciclib) or placebo combined with ET (aromatase inhibitors or fulvestrant) and a CDK4/6 inhibitor (ribociclib, palbociclib, or abemaciclib).REC name
West of Scotland REC 1
REC reference
25/WS/0188
Date of REC Opinion
25 Feb 2026
REC opinion
Further Information Favourable Opinion