Study of Orally Administered MOMA-341 in Participants With Advanced or Metastatic Solid Tumors

Inclusion Criteria:

1. Age ≥ 18 years

2. Participants have unresectable advanced or metastatic solid tumors with MSI-H ordMMR alterations and histologically confirmed disease. Participants must havepreviously received and progressed on an anti-PD-(L)1-based regimen, unlessineligible or in a region without access to anti-PD-(L)1 therapies

3. Have at least 1 lesion at baseline (measurable or non-measurable) suitable forrepeat imaging evaluation by RECIST and/or PCWG-3

4. ECOG PS ≤ 2

5. Fully recovered from clinically relevant effects of prior therapy, radiotherapy,and/or surgery **hormonal therapy allowed. Palliative radiotherapy allowed

6. Adequate organ function per local labs

7. Comply with contraception requirements

8. Written informed consent must be obtained according to local guidelines

Exclusion Criteria:

1. Known Werner Syndrome

2. Active prior or concurrent advanced-stage malignancy (some exceptions allowedincluding early-stage cancers)

3. Clinically relevant cardiovascular disease

4. Known CNS metastasis associated with progressive neurological symptoms (stable dosesof corticosteroids allowed)

5. Known active uncontrolled infection

6. Known allergy, hypersensitivity, and/or intolerance to MOMA-341

7. Impaired GI function that may impact absorption

8. Patient is pregnant or breastfeeding

9. Known to be HIV positive, unless all of the following criteria are met:

10. Undetectable viral load or CD4+ count ≥300 cells/μL

11. Receiving highly active antiretroviral therapy

12. No AIDS-related illness within the past 12 months

13. Active liver disease (some exceptions are allowed)

14. Prior or ongoing condition, therapy, or laboratory abnormality that, in theinvestigator's opinion, may affect safety of the patient, confound the results ofthe study, and/or interfere with the patients participation in the study