Evaluating BDTX-4933 for patients with specific cancer mutations

A Phase 1/2, Open-label Study of Oral S241656 (BDTX-4933) as Monotherapy and in Combination With Other Anti-Cancer Therapies in Patients With KRAS, BRAF and Other Selected RAS/MAPK Mutation-Positive Malignancies

PHASE1; PHASE2 · Servier · NCT05786924

This study is testing a new drug called BDTX-4933 to see if it can help adults with advanced cancers that have certain gene mutations feel better and improve their treatment options.

Quick facts

PhasePHASE1; PHASE2
Study typeInterventional
Enrollment554 (estimated)
Ages18 Years and up
SexAll
SponsorServier (industry)
Drugs / interventionschemotherapy, radiation
Locations11 sites (Gilbert, Arizona and 10 other locations)
Trial IDNCT05786924 on ClinicalTrials.gov

What this trial studies

This Phase 1 clinical trial investigates the safety, tolerability, and preliminary effectiveness of BDTX-4933 in adults with advanced or metastatic cancers that have specific mutations in the KRAS, BRAF, or NRAS genes. The study consists of a dose escalation phase to determine the maximum tolerated dose and an expansion cohort focusing on non-small cell lung cancer with KRAS non-G12C mutations. Patients will take BDTX-4933 orally in 28-day cycles until their disease progresses or they choose to withdraw. The trial aims to provide insights into the drug's antitumor activity in these mutation-positive cancers.

Who should consider this trial

Good fit: Ideal candidates include adults with recurrent advanced or metastatic solid tumors or histiocytic neoplasms that have documented RAS or BRAF mutations.

Not a fit: Patients with active central nervous system metastases or primary CNS tumors with progressive neurological symptoms are unlikely to benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could offer a new therapeutic option for patients with specific mutation-positive cancers that currently have limited treatment options.

How similar studies have performed: Other studies targeting similar mutations in cancers have shown promising results, suggesting that this approach may be effective.

Eligibility criteria

Show full inclusion / exclusion criteria
Key Inclusion Criteria:

* Life expectancy of ≥ 12 weeks in the opinion of the investigator.
* Histologically or cytologically confirmed recurrent locally advanced (unresectable) or metastatic solid tumors with documented RAS or RAF mutations or alterations.
* Adequate bone marrow and organ function.
* Recovered from toxicity to prior anti-cancer therapy.

Part 1 Dose Escalation cohort ONLY:

* Part 1A: Advanced/metastatic NSCLC with KRAS non-G12C, HRAS, NRAS, BRAF or CRAF (RAF1) mutations or alterations
* Part 1B: Advanced/metastatic GI tumors (e.g., PDAC, CRC, and BTC) with KRAS, HRAS, NRAS, BRAF, and/or CRAF (RAF1) mutations or alterations
* Part 1C: Advanced/metastatic PDAC with KRAS, HRAS, NRAS, BRAF, and/or CRAF (RAF1) mutations or alterations
* Part 1D: Colorectal adenocarcinoma with KRAS, HRAS, NRAS, BRAF, and/or CRAF (RAF1) mutations or alterations
* Part 1E: Other advanced/metastatic non-GI, non-NSCLC solid tumors with KRAS, HRAS, NRAS, BRAF, CRAF (RAF1) mutations or alterations

Part 2 Dose Optimization and Expansion cohorts ONLY:

* Part 2A: Advanced/metastatic NSCLC with KRAS non-G12C mutations and/or BRAF mutations
* Part 2A1: Advanced/metastatic NSCLC with KRAS non-G12C mutations
* Part 2A2: Advanced/metastatic NSCLC with BRAF mutations
* Part 2A3: Advanced/metastatic NSCLC with KRAS non-G12C or BRAF mutations or alterations and active CNS metastatic disease
* Part 2A4: Advanced/metastatic NSCLC with a KRAS G12C mutation
* Part 2B1: Advanced/metastatic PDAC with KRAS, HRAS, NRAS, BRAF, and/or CRAF (RAF1) mutations or alterations
* Part 2B2: Advanced/metastatic CRC with KRAS, HRAS, NRAS, BRAF, and/or CRAF (RAF1) mutations or alterations
* Part 2B3: Advanced/metastatic BTC (adenocarcinoma) with KRAS, HRAS, NRAS, BRAF, and/or CRAF (RAF1) mutations or alterations

Key Exclusion Criteria:

* Cancer that has a known MEK1/2 mutation.
* Known allergy/hypersensitivity to excipients of S241656 or to any of the registered IMPs administered in combination.
* Any contra-indication, to use of any of the combination chemotherapy or anti-EGFR therapy partners administered as part of this trial.
* Major surgery within 4 weeks of study entry or planned during study.
* Ongoing anticancer therapy.
* Ongoing radiation therapy.
* Uncontrolled or active clinically relevant bacterial, fungal, or specific viral infection requiring systemic therapy.
* Clinically significant cardiovascular disease.
* Symptomatic spinal cord compression.
* Evidence of active malignancy (other than study-specific malignancies) requiring systemic therapy within the next 2 years.
* History or current evidence of retinal vein occlusion (RVO) or current risk factors for RVO.
* Females who are pregnant or breastfeeding.
* Actively receiving systemic treatment or direct medical intervention on another therapeutic clinical study.
* Prior use of experimental agents that target the KRAS/BRAF/MEK/ERK pathway.

Where this trial is running

Gilbert, Arizona and 10 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Non-small Cell Lung Cancer, Histiocytic Neoplasm, Histiocytosis, BRAF Gene Mutation, BRAF V600E, BRAF V600 Mutation, BRAF Mutation-Related Tumors, BRAF

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.