First-in-Human Study of Mutant-selective PI3Kα Inhibitor, RLY-2608, As a Single Agent in Advanced Solid Tumor Patients and in Combination with Fulvestrant in Patients with Advanced Breast Cancer

Description

This is an open-label, FIH study designed to evaluate the maximum tolerated dose, recommended Phase 2 dose, safety, tolerability, PK, pharmacodynamics, and preliminary antineoplastic activity of RLY-2608, in advanced solid tumor patients with a Phosphatidylinositol-4,5-bisphosphate-3 kinase, catalytic subunit alpha (PIK3CA) mutation in blood and/or tumor per local assessment. The study will evaluate RLY-2608 as a single agent for patients with unresectable or metastatic solid tumors. It will also evaluate RLY-2608 in combination RLY-2608 + fulvestrant and in triple combination RLY-2608 + fulvestrant + CDK4/6 inhibitor (palbociclib or ribociclib) or CDK4 inhibitor (PF-07220060) for patients with HR+ HER2- locally advanced or metastatic breast cancer or endometrial cancer (palbociclib or ribociclib Part 1). The RLY-2608 single agent arm, RLY-2608 + fulvestrant combination arm, and triple combination arms will have 2 parts: a dose escalation (Part 1) and a dose expansion (Part 2).

Conditions

PIK3CA Mutation, Solid Tumor, Adult, HER2-negative Breast Cancer, Breast Cancer, Metastatic Breast Cancer, Advanced Breast Cancer, Unresectable Solid Tumor, Endometrial Cancer

Study Overview

Study Details

Study overview

This is an open-label, FIH study designed to evaluate the maximum tolerated dose, recommended Phase 2 dose, safety, tolerability, PK, pharmacodynamics, and preliminary antineoplastic activity of RLY-2608, in advanced solid tumor patients with a Phosphatidylinositol-4,5-bisphosphate-3 kinase, catalytic subunit alpha (PIK3CA) mutation in blood and/or tumor per local assessment. The study will evaluate RLY-2608 as a single agent for patients with unresectable or metastatic solid tumors. It will also evaluate RLY-2608 in combination RLY-2608 + fulvestrant and in triple combination RLY-2608 + fulvestrant + CDK4/6 inhibitor (palbociclib or ribociclib) or CDK4 inhibitor (PF-07220060) for patients with HR+ HER2- locally advanced or metastatic breast cancer or endometrial cancer (palbociclib or ribociclib Part 1). The RLY-2608 single agent arm, RLY-2608 + fulvestrant combination arm, and triple combination arms will have 2 parts: a dose escalation (Part 1) and a dose expansion (Part 2).

A First-in-Human Study of Mutant-selective PI3Kα Inhibitor, RLY-2608, As a Single Agent in Advanced Solid Tumor Patients and in Combination with Fulvestrant in Patients with Advanced Breast Cancer

First-in-Human Study of Mutant-selective PI3Kα Inhibitor, RLY-2608, As a Single Agent in Advanced Solid Tumor Patients and in Combination with Fulvestrant in Patients with Advanced Breast Cancer

Condition
PIK3CA Mutation
Intervention / Treatment

-

Contacts and Locations

Tucson

The University of Arizona Cancer Center, Tucson, Arizona, United States, 85724

San Diego

University of California-San Diego, San Diego, California, United States, 90293

Denver

HealthONE, Denver, Colorado, United States, 80218

New Haven

Yale University, New Haven, Connecticut, United States, 06510

Orlando

Florida Cancer Specialists, Orlando, Florida, United States, 32827

Plantation

Boca Raton Clinical Research (BRCR) Global, Plantation, Florida, United States, 33322

Chicago

University of Chicago Medical Center, Chicago, Illinois, United States, 60637

Indianapolis

Community Health Network, Indianapolis, Indiana, United States, 46250

Boston

Massachusetts General Hospital, Boston, Massachusetts, United States, 02114

Boston

Dana-Farber Cancer Institute, Boston, Massachusetts, United States, 02215

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

For general information about clinical research, read Learn About Studies.

Eligibility Criteria

    Ages Eligible for Study

    18 Years to

    Sexes Eligible for Study

    ALL

    Accepts Healthy Volunteers

    No

    Collaborators and Investigators

    Relay Therapeutics, Inc.,

    Study Record Dates

    2026-08-31