Updated June 2026 · ClinicalTrials.gov

RECRUITINGPhase 1INTERVENTIONAL

A Trial of RSC-1255 for Treatment of Patients With Advanced Malignancies

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

A Trial of RSC-1255 for Treatment of Patients With Advanced Malignancies (NCT04678648) is a Phase 1 interventional studying Advanced Malignant Solid Neoplasm and RAS Mutation, sponsored by RasCal Therapeutics, Inc.. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

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.

What Stage of Research Is This?

Phase 1 trials test a new treatment for the first time in humans, focusing on safety, dosing, and how the body processes the drug. For Advanced Malignant Solid Neoplasm, a Phase 1 study typically enrolls a small number of participants — often healthy volunteers or patients who have exhausted standard treatment options. Phase 1 results determine whether a treatment moves into larger Phase 2 efficacy studies.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

Target enrollment of 134 participants puts this in the typical range for a Phase 2-style efficacy study or a moderate Phase 3 trial in a focused Advanced Malignant Solid Neoplasm subpopulation. At this scale, the study has enough statistical power to detect a clear treatment effect but is not the largest cohort in the field.

Who May Be Eligible (Plain English)

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 Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

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

Treatments Being Tested

DRUG

RSC-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.

DRUG

RSC-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.

Locations (3)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

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

Los Angeles, California, United States

Sarah Cannon, SCRI Oncology Partners - Health One

Denver, Colorado, United States

Sarah Cannon, SCRI Oncology Partners

Nashville, Tennessee, United States

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT04678648), the sponsor (RasCal Therapeutics, Inc.), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT04678648 clinical trial studying?

Who can participate in NCT04678648?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT04678648?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Related Advanced Malignant Solid Neoplasm Trials

TR-002 for the Treatment of Advanced, Unresectable or Metastatic Solid Tumors and Unresectable or Metastatic, Refractory Pancreatic Adenocarcinoma

Phase 1 · University of California, Davis

CPI-613 (Devimistat) in Combination With Hydroxychloroquine and 5-fluorouracil or Gemcitabine in Treating Patients With Advanced Chemorefractory Solid Tumors

Phase 2 · Northwestern University

IACS-6274 With or Without Bevacizumab and Paclitaxel for the Treatment of Advanced Solid Tumors

Phase 1 · M.D. Anderson Cancer Center

Morning Versus Afternoon Administration of Immunotherapy for the Treatment of Advanced or Metastatic Solid Tumors, The Knight SHIFT Study

Phase 4 · OHSU Knight Cancer Institute

Source: ClinicalTrials.gov API v2 record for NCT04678648. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT04678648. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-06-26 · Data from ClinicalTrials.gov.