Phase 1/2 Study of ETX-636 in Participants With Advanced Solid Tumors

Conditions

• Advanced Breast Cancer
• Advanced Solid Tumors

Eligibility Criteria

Sex

ALL

Age

18 Years - N/A

Healthy Volunteers

Not accepted

Interventions

• ETX-636 dose escalation — DRUG
  ETX-636 is a pan-mutant-selective PI3Kα Inhibitor and degrader in the form of an oral tablet that will be taken once per day in 28-day cycles, to evaluate escalating dose levels.
• ETX-636 dose escalation in combination with fulvestrant — DRUG
  ETX-636 is a pan-mutant-selective PI3Kα Inhibitor and degrader in the form of an oral tablet. ETX-636 will be taken in combination with fulvestrant in 28-day cycles, to evaluate escalating dose levels. EXT-636 is an oral tablet that will be taken once per day. Fulvestrant will be administered as an injection 2 weeks apart in the first 28 days, followed by monthly injections.
• ETX-636 dose expansion in combination with fulvestrant — DRUG
  ETX-636 is a pan-mutant-selective PI3Kα Inhibitor and degrader in the form of an oral tablet. ETX-636 will be taken in combination with fulvestrant in 28-day cycles, to expand selected dose levels. EXT-636 is an oral tablet that will be taken once per day. Fulvestrant will be administered as an injection 2 weeks apart in the first 28 days, followed by monthly injections.

Study Details

Phase 1/2, open-label study of ETX-636 in participants with advanced solid tumors

Key Dates

Start date

Jun 10, 2025

Status verified

May 2026

Primary completion

Jun 30, 2027

Completion

Dec 30, 2027

Study Design

Enrollment

233 participants (estimated)

Allocation

NON_RANDOMIZED

Intervention model

SEQUENTIAL

Primary purpose

TREATMENT

Arms

• Experimental: Part A Dose Escalation Monotherapy (Advanced Solid Tumors with PIK3CA mutation)
  Part A is a dose escalation monotherapy of ETX-636 in advanced solid tumors with PIK3CA mutation
• Experimental: Part B Dose Escalation Combination Therapy (HR+/HER2- locally advanced or metastatic breast cancer)
  Part B is a dose escalation combination therapy in HR+/HER2- locally advanced or metastatic breast cancer. The study treatment will be ETX-636, a pan-mutant-selective PI3Kα inhibitor, in combination with fulvestrant (Faslodex) at a fixed dose of 500 mg IM.
• Experimental: Part C Dose Expansion Combination Therapy (HR+/HER2- locally advanced or metastatic breast cancer)
  Part B is a dose expansion combination therapy in HR+/HER2- locally advanced or metastatic breast cancer. The study treatment will be ETX-636, a pan-mutant-selective PI3Kα inhibitor, in combination with fulvestrant (Faslodex) at a fixed dose of 500 mg IM.

Primary Outcome Measure

Evaluate Safety and Tolerability of ETX-636 monotherapy in Part A and ETX-636 plus fulvestrant combination therapy in Part B [ Time Frame: First 28 days of treatment ]

Central Contacts

• Janaki Parameswaran, MD
  1-617-383-4993
  [email protected]
• Melinda Snyder
  1-617-383-4993
  [email protected]

Locations (10)

Find similar trials in Newport Beach, CA

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