Study of IDE397 in Participants With Solid Tumors Harboring MTAP Deletion

An Open Label, Phase 1, Treatment Study to Evaluate the Safety, Pharmacokinetics and Pharmacodynamics of IDE397 (MAT2A Inhibitor) In Adult Participants With Advanced Solid Tumors

This is a Phase 1, open-label, multicenter, dose escalation and expansion study of the safety, PK, PD, and preliminary anti-tumor activity of IDE397 as a single agent and in combination with sacituzumab govitecan (SG), in adult patients with selected advanced or metastatic MTAP-deleted advanced solid tumors who are unresponsive to standard of care therapy. IDE397 is a small molecule inhibitor of methionine adenosyltransferase 2 alpha (MAT2A).

Inclusion Criteria:

• Participant must be at least 18 years of age
• Advanced or metastatic solid tumor that has progressed on at least one prior line of treatment or is intolerant to additional effective standard therapy
• Have evidence of homozygous loss of MTAP or MTAP deletion
• Willing to undergo paired fresh biopsy (pre- and post-treatment) procedure. Exceptions may be made for feasibility and safety concerns
• Measurable disease
• ECOG performance status <= 1
• Adequate organ function
• Able to swallow and retain orally administered study treatment
• Recovery from acute effects of prior therapy
• Able to comply with contraceptive/barrier requirements

Exclusion Criteria:

• Known symptomatic brain metastases
• Known primary CNS malignancy
• Current active liver or biliary disease
• Impairment of gastrointestinal (GI) function
• Active uncontrolled infection
• Clinically significant cardiac abnormalities
• Active second malignancy or history of another malignancy in the past 2 years
• Previous treatment with a MAT2A inhibitor and / or PRMT inhibitor or sacituzumab govitecan
• Systemic anti-cancer therapy, therapeutic antibody treatment, or major surgery within 4 weeks prior to study entry
• Current radiation-related toxicity or radiation therapy within 2 weeks prior to study entry
• Small molecule anti-cancer treatment within 2 weeks prior to study entry
• Prior irradiation to >25% of the bone marrow
• Current use or anticipated need for food or drugs that are known strong CYP3A4/5 inhibitors or inducers
• Require concomitant use of proton pump inhibitor
• Currently receiving another investigational study drug.
• Known or suspected hypersensitivity to IDE397/excipients or components