Treatment of advanced cancers with RSC-1255

A Phase Ia/Ib, Open Label, Multi-center, Non-randomized Dose Escalation and Dose Expansion Study of RSC-1255 Alone or in Combination With Hydroxychloroquine in Patients With Advanced Solid Tumor Malignancies

Phase 1 Interventional RasCal Therapeutics, Inc. · NCT04678648

This study is testing a new oral drug called RSC-1255 to see if it can help adults with advanced cancers that haven't responded to other treatments.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment134 (estimated)
Ages18 Years and up
SexAll
SponsorRasCal Therapeutics, Inc. Industry-sponsored
Locations3 sites (Los Angeles, California and 2 other locations)
Trial IDNCT04678648 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates RSC-1255, an oral small-molecule inhibitor targeting RAS mutations, in adults with advanced solid tumors who have not responded to existing therapies. The trial consists of two phases: Phase 1a focuses on determining the maximum tolerated dose, while Phase 1b aims to assess the safety and efficacy of the drug. Approximately 134 participants will receive RSC-1255 twice daily as monotherapy. The study is open-label and multi-center, allowing for a diverse participant pool.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with advanced solid tumors that are refractory to or have progressed after standard therapies.

Not a fit: Patients currently receiving cancer therapy or those with significant comorbidities affecting major organ systems may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new option for patients with advanced malignancies who have limited therapeutic alternatives.

How similar studies have performed: While this approach is novel in its specific targeting of RAS mutations, similar studies targeting advanced malignancies have shown promise in the past.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria (Key Factors):

1. Has pathologically confirmed advanced or metastatic malignancy characterized by one or more of the following:

   * Participant is intolerant of existing therapy(ies) known to provide clinical benefit for their condition
   * Malignancy is refractory to existing therapy(ies) known to potentially provide clinical benefit
   * Malignancy has progressed on standard therapy
2. Has evaluable or measurable tumor(s) in dose-escalation by standard radiological and/or laboratory assessments as applicable to their malignancy.
3. Has adequate performance status (PS): Eastern Co-operative Oncology Group (ECOG).
4. Is age ≥ 18 years.
5. Has either tissue agnostic tumors and documented RAS mutations or with glioblastoma with or without mutation in RAS

Exclusion Criteria (Key Factors):

1. Participants receiving cancer therapy at the time of enrollment.
2. Any clinically significant disease or condition affecting a major organ system.
3. Significant cardiovascular disease or electrocardiogram (ECG) abnormalities.
4. Known Gilbert's disease.
5. Has had a previous (within 2 years) or has a current malignancy other than the target cancer.
6. Intermittent hypokalemia
7. Grade 1 or higher nausea, vomiting, diarrhea at baseline due to underlying disease

Where this trial is running

Los Angeles, California and 2 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.
Conditions Advanced Malignant Solid NeoplasmRAS MutationLung CancerColon CancerGlioblastomaPancreatic CancerMalignancyCancer
Last reviewed 2026-06-13 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.