The main purpose of this study is to assess safety & tolerability and antitumor activity of LY3962673 as monotherapy and in combination with other chemotherapy agents in participants with KRAS G12D-mutant advanced solid tumor types. The study is expected to last approximately 5 years.

Inclusion Criteria:

• Have Histological or cytologically proven diagnosis of locally advanced, unresectable, and/or metastatic cancer and measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1.
• Have evidence of KRAS G12D mutation in tumor tissue or circulating tumor DNA
• Have an ECOG performance status of ≤ 1
• Must have received ≥ 1 prior line of systemic chemotherapy for advanced or metastatic disease
• Participants with asymptomatic or treated CNS disease may be eligible.

Exclusion Criteria:

• Have known active CNS metastases and/or carcinomatous meningitis.
• Have any unresolved toxicities from prior therapy greater than National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v5.0 Grade 1.
• Have significant cardiovascular disease as unstable angina or acute coronary syndrome, history of myocardial infarction, known reduced left ventricular ejection fraction.
• Have active uncontrolled systemic bacterial, viral, fungal, or parasitic infection.
• Have known active hepatitis B virus (HBV) and hepatitis C virus (HCV).
• Have other active malignancy unless in remission with life expectancy greater than (>) 2 years.