About this trial

A multicenter, single-arm, first-in-human study to investigate the safety, pharmacokinetics, and preliminary antitumor activity of PLX-61639 in participants with locally advanced or metastatic, relapsed/refractory, SMARCA4-deficient solid tumors who are intolerant of or have failed available, approved therapies.

The study will be conducted in 3 parts: dose escalation (Part 1), dose optimization (Part 2), and cohort expansion (Part 3). Each part of the study will consist of a Screening Phase lasting up to 28 days during which participants will be assessed for eligibility, a Treatment Phase beginning on Cycle 1 Day 1 and consisting of consecutive 28-day cycles, an End of Treatment Visit, and a Post-Treatment Follow-Up Phase.

Participants will receive their assigned dose of PLX-61639 administered orally, once daily until progression/relapse, intolerance, death, or withdrawal from study treatment by the Investigator or participant.

Eligibility criteria

Qualifiers

Participants with locally advanced or metastatic, relapsed/refractory, solid tumors harboring a SMARCA4 loss-of-function mutation that have progressed on, are intolerant of, or not otherwise candidates for available approved therapies

Adequate liver bone marrow, coagulation, renal, and cardiopulmonary function

Measurable disease per RECIST 1.1

ECOG PS of 0 or 1

Disqualifiers

Germline SMARCA4 mutations

Known SMARCA2 mutation or loss of expression

Symptomatic CNS disease

Prior treatment with another SMARCA2-directed therapy

Trial design

Treatments tested in this trial

  • PLX-61639

Treatment groups

155 Participants
are divided into 1 treatment group

Locations

10
Arizona
Research Site85258, Scottsdale United States
California
Research Site91010, Duarte United States
Research Site92868, Orange United States
Massachusetts
Research Site02114, Boston United States

Sponsors and collaborators

Plexium, Inc.

Lead sponsor