A Phase 1/2a, Open-Label Study of Safety, Tolerability, Pharmacokinetics, and Preliminary Efficacy of SA53-OS, an MDM2 Inhibitor, in Patients With Locally Advanced or Metastatic p53 Wild-Type Solid Tumors
The objective of this study is to assess the safety, efficacy, and pharmacokinetics of SA53-OS in adult participants with refractory solid tumors. The study is comprised of 2 parts: Part 1 called dose escalation, and Part 2a called dose expansion. This study starts with Part 1 where participants who are diagnosed with advanced or metastatic solid tumor cancers receive different doses of SA53-OS (starting with the lowest dose) to find the maximum tolerated dose (MTD) of SA53-OS. Once the MTD of SA53-OS is known, the study continues to Part 2a where participants who are diagnosed with dedifferentiated liposarcoma (DD LPS) or other solid tumor cancers will receive SA53-OS at the MTD. The study drug, SA53-OS, will be administered for 3 consecutive days every 3 weeks as an oral solution for up to 2 years.
• Tumor characteristics of participants in Phase 1
‣ Histologically and/or cytologically confirmed diagnosis of advanced or metastatic solid tumor and/or non-Hodgkin lymphoma excluding primary central nervous system malignancy for which no standard effective treatment exists or where that treatment was declined. Participants with non-Hodgkin lymphoma should have failed ≥ 2 prior lines of systemic therapy prior enrollment.
⁃ Tumor p53 wild-type.
• Tumor characteristics of participants in Phase 2a
‣ Cohort A: Tumor p53 wild-type with histologically confirmed diagnosis of advanced or metastatic DD LPS (and MDM2 amplification); OR Cohort B: Tumor p53 wild-type in other solid tumor.
⁃ Measurable disease by RECIST 1.1.
• 18 years old or older.
• Resolution of clinically relevant toxicity-related to prior anticancer therapies prior to receipt of study treatment to Grade 1 or less.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
• Participants of childbearing/reproductive potential must agree to use adequate birth control measures during the course of the trial and for at least 3 months after discontinuing study treatment.