This is a first-in-human (FIH), multicenter, open-label, dose-escalation, and dose-expansion Phase 1/2 clinical trial to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary efficacy of D3S-001 or combination therapy in subjects with advanced KRAS p.G12C mutant solid tumors. D3S-001 will be taken daily by oral administration in 21-day treatment cycles.

Inclusion:

• Subject must have a histologically or cytologically confirmed metastatic or locally advanced solid tumor which is progressing.
• Subject must have documented KRAS p.G12C mutation identified within the last 5 years by a local test on tumor tissue or blood.
• Subject must have measurable disease per RECIST v1.1.
• Subject must have Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
• Subject must have adequate organ and marrow function within the screening period.

Exclusion:

• Subject has any prior treatment with other treatments without adequate washout periods as defined in the protocol.
• Subject has uncontrolled intercurrent illness, including but not limited to, ongoing or active infection, uncontrolled or significant cardiovascular disease, serious chronic gastrointestinal conditions associated with diarrhea, or psychiatric illness/social situations that would limit compliance with study requirements, substantially increase risk of incurring AEs, or compromise the ability of the subject to give written informed consent.
• Subject has unresolved treatment-related toxicities from previous anticancer therapy of NCI CTCAE Grade ≥2 (with exception of vitiligo or alopecia).
• Subject has active gastrointestinal disease or other that could interfere significantly with the absorption, distribution, metabolism, or excretion of oral therapy.
• Concurrent participation in any clinical research study involving treatment with any investigational drug, radiotherapy, or surgery, except for the nontreatment phases of these studies (e.g., follow-up phase).

Other protocol inclusion/exclusion criteria may apply