A Single-Arm, Open-Label Phase Ia/Ib Clinical Trial Evaluating the Safety, Tolerability, Pharmacokinetic Profile, and Preliminary Efficacy of FS-207 in Patients With Advanced Solid Tumors With High Microsatellite Instability (MSI-H)

brief summary

This is a Phase Ia/Ib clinical study of FS-207, an investigational oral tablet, in patients with advanced solid tumors that are microsatellite instability-high, also called MSI-H. MSI-H tumors have specific changes in DNA repair pathways and may depend on the WRN protein to survive. FS-207 is designed to inhibit WRN. The main purpose of this study is to evaluate the safety and tolerability of FS-207 and to understand how the drug moves through the body. The study will also look for early signs of anti-tumor activity. This study has two parts. In the first part, called dose escalation, small groups of patients will receive increasing dose levels of FS-207 to help identify a safe and appropriate dose for further study. In the second part, called dose expansion, additional patients with selected MSI-H advanced solid tumors will receive FS-207 at dose level(s) chosen based on the earlier safety and clinical data. Participants will take FS-207 orally once daily. Study doctors will monitor participants closely through physical examinations, blood and urine tests, electrocardiograms, heart function tests, imaging scans, and blood samples for pharmacokinetic testing. Tumor assessments will be performed regularly to evaluate whether the cancer has responded to treatment, remained stable, or progressed. This is an open-label study, which means that both the participants and study doctors will know that FS-207 is being given. There is no placebo group in this study.