A Phase 1 interventional study of RSC-1255 Dose Escalation and RSC-1255 Dose Expansion in Advanced Malignant Solid Neoplasm, RAS Mutation and Lung Cancer, sponsored by RasCal Therapeutics, Inc.. Recruiting at 3 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-23.
Sponsored by RasCal Therapeutics, Inc. · Phase 1, Interventional, and Treatment
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.
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).
5,422 studies on the registry are indexed under Lung Neoplasms; 1,346 are open to participants now.
This study's planned enrollment of 134 is above the median of 60 across 3,656 interventional studies indexed under Lung Neoplasms.
Browse Lung Neoplasms studies →This is the only study on the registry with RasCal Therapeutics, Inc. as lead sponsor.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Has confirmed advanced or characterized by one or more of the following:
Exclusion Criteria (Key Factors):
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Single Arm Study. All study participants receive RSC-1255.
Drug: RSC-1255 Dose Escalation · Drug: RSC-1255 Dose Expansion
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.
Also known as: Phase 1a, Dose Escalation
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.
Also known as: Phase 1b, Dose Expansion
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
Adverse event profile of RSC-1255
Toxicities will be graded according to CTCAE V5.0.
Time frame: Approximately 24 months
Overall Survival (OS)
Overall Survival
Time frame: Approximately 24 months
Disease Progression
Disease Progression will be assessed using RECIST V1.1
Time frame: Approximately 24 months
Plan to share: No
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