RecruitingInterventionalPhase 1

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

NCT ID: NCT04678648Sponsor: RasCal Therapeutics, Inc.Last updated: 2026-03-18

Summary

RSC-101 is a Phase 1a/1b clinical trial of RSC-1255 in adult study participants with advanced solid tumor malignancies who are intolerant of existing therapies known to provide clinical benefit, have disease that has progressed after standard therapy, or have previously failed other therapies. The study has two phases. The purpose of Phase 1a (Dose Escalation) is to confirm the appropriate treatment dose and Phase 1b (Dose Expansion) is to characterize the safety and efficacy of RSC-1255.

Detailed description

RSC-1255 is an orally bioavailable, small-molecule direct pan-mutant and wild-type RAS inhibitor. RSC-101 is a Phase 1a/1b, open-label, multi-center, non-randomized, Dose Escalation and Dose Expansion study in participants with advanced solid tumor malignancies. Study enrollment is approximately 134 participants. All participants receive oral RSC-1255, twice daily as monotherapy. Following Phase 1a (Dose Escalation) to identify the Maximum Tolerated Dose and Recommended Dose for use in Phase 1b, additional participants are enrolled in the Phase 1b (Dose Expansion) to further characterize the safety, pharmacology, and the clinical efficacy of RSC-1255 as monotherapy and in combination with the autophagy inhibitor hydroxychloroquine (HCQ).

Arms & interventions

DrugRSC-1255 Dose Escalation
Phase 1a will enroll 40-80 participants to identify the dose limiting toxicity (DLT), recommended Phase 1b dose, and the safety and tolerability of RSC-1255. RSC-1255 is administered orally twice daily, with and without food. Each cycle is 21 days.
DrugRSC-1255 Dose Expansion
Phase 1b will enroll 48-94 participants to further characterize the safety, pharmacology, and clinical efficacy of RSC-1255. RSC-1255 is administered orally twice daily alone or in combination with continuous hydroxychloroquine, with food. Each cycle is 21 days.

Outcome measures

Primary

Maximum Tolerated Dose (MTD) for RSC-1255 as monotherapy
The number and type of dose-limiting toxicities (DLTs) as defined in the protocol that occur during the first 21 days of treatment and maximum grade of all treatment-related events using CTCAE V5.0 will be used to identify a safe and tolerable dose.
Time frame: Approximately 30 months
Recommended Phase 2 Dose (RP2D) for RSC-1255 as monotherapy
The number and type of DLTs as defined in the protocol that occur during the first 21 days of treatment and maximum grade of all treatment-related adverse events using CTCAE 5.0 will be used to identify a safe and tolerable dose.
Time frame: Approximately 12 months

Secondary

Adverse event profile of RSC-1255
Time frame: Approximately 24 months
Overall Survival (OS)
Time frame: Approximately 24 months
Disease Progression
Time frame: Approximately 24 months

Eligibility criteria

Sex: AllAge: 18 Years and olderHealthy volunteers: No

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

Study locations (3)

University of California, Los Angeles (UCLA) Department of Medicine - Hematology/Oncology

Los Angeles, California, 90404

Recruiting

Sarah Cannon, SCRI Oncology Partners - Health One

Denver, Colorado, 80218

Recruiting

Sarah Cannon, SCRI Oncology Partners

Nashville, Tennessee, 37203

Recruiting