Safety and Tolerability Study of GIM-531 in Advanced Solid Tumors

Key Inclusion Criteria:

• Written informed consent

• Cytologically or histologically confirmed locally advanced or metastatic solid tumorthat has progressed on standard therapy or for which no standard therapy exist; orbe intolerant of standard therapy

• Have not received an experimental drug within 4 weeks or 5 half-lives (whichever isshorter) of study drug treatment or already be enrolled in a clinical study

• ECOG performance status 0-1

• Laboratory and ECG assessments within 28 days of enrollment including acceptablecardiac, renal, and hepatic functions

• Agree to baseline core needle biopsy or archival (within 12 months of screening)tumor submission; Note: Participants whose only site(s) of disease are in areasconsidered moderate or high risk for biopsy complications may be enrolled without afresh biopsy upon Sponsor approval.

• Non pregnant participants; female participants of child bearing potential withnon-sterile partners agree to use an effective form of contraception from the timeof first dose of study drug (or 14 days prior to first dose for oral contraception)until 7 months after the last dose of study drug. Effective forms of contraceptioninclude hormonal (injection or oral), double barrier method, or intrauterine device.Non-sterile male participants with sexual partners of childbearing potential agreeto use a barrier contraception method and agree to not donate sperm from the time offirst dose of study drug until 4 months after the last dose of study drug.

• Measurable disease according to Response Evaluation Criteria in Solid Tumors (RECIST) version (v)1.1

Phase 1 Expansion Cohorts Specific Inclusion Criteria (in addition to above inclusion criteria):

• NSCLC: Participants must have locally advanced/unresectable or metastatic NSCLC.Participants must have received ≤2 prior lines of therapy in the advanced/metastaticsetting.

• TNBC: Participants must have locally advanced unresectable, recurrent, or metastaticTNBC. Participants must have received ≤2 prior lines of therapy in theadvanced/metastatic setting. TNBC participants with germline BRCA1/2 mutations musthave received ≤3 prior lines of therapy in the advanced/metastatic setting.

• Ovarian Cancer: Participants must have locally advanced unresectable, recurrent, ormetastatic ovarian cancer. Participants must have received ≤2 prior lines of therapyin the advanced/metastatic setting with or without maintenance treatment.

• Tumors with AKT3 mutation/amplification: Participants must have a locally advancedunresectable, recurrent, or metastatic solid malignancy. Participants with knownAKT3 mutation/amplification based on next generation sequencing (NGS) performed perlocal standard of care.

Phase 2 Specific Inclusion Criteria (in addition to above inclusion criteria):

• Have confirmed unresectable Stage III or metastatic Stage IV cutaneous melanoma thathas radiographically progressed (as confirmed by imaging assessed by theInvestigator) on an approved first-line single-agent or combination anti-PD-1therapy

• Receiving anti-PD-1 therapy as their first line of treatment at the time ofenrollment and amenable to continuing anti-PD-1 therapy during the study

Key Exclusion Criteria:

• Ongoing >Grade 1 toxicity from prior therapy according to Common TerminologyCriteria for Adverse Events v5.0 (Note: Grade 2 alopecia and Grade 2 sensoryneuropathy are not exclusionary)

• Has melanoma with documented BRAF mutation (Phase 2 only)

• Has known leptomeningeal disease, spinal cord compression, or brain metastases,except participants with the following:

• Brain metastases that have been treated and are clinically stable for at least 4 weeks prior to the first administration of study drug; Note: Participantsreceiving steroids for brain metastases must be either off steroids or on astable, or decreasing dose, of <10 mg daily of prednisone (or equivalent) inorder to be eligible for enrollment; and

• No ongoing neurological symptoms related to the anatomic location of the brainmetastases.

Note: Neurological symptoms that are considered sequelae to treatment for brain metastases are allowed.

• Has known structural cardiac disease

• Has known serious arrythmia, serious dysrhythmia, history of long QT syndrome, orclinically relevant cardiac conduction abnormalities

• Has an active autoimmune disease that has required systemic treatment in the past 2years (ie, with use of disease modifying agents, corticosteroids, orimmunosuppressive drugs). Replacement therapy (eg, thyroxine, insulin, orphysiologic corticosteroid replacement therapy for adrenal or pituitaryinsufficiency) is not considered a form of systemic treatment and is allowed.

• At time of screening, is receiving systemic steroid therapy (greater than or equalto 10 mg/day of prednisone or equivalent) or is taking any immunosuppressivetherapy; Note: Use of topical, inhaled, nasal, or ophthalmic steroids is allowed.

• Has active and clinically significant bacterial, fungal, or viral infection,including known hepatitis B virus (HBV), hepatitis C virus (HCV), or humanimmunodeficiency virus (HIV)

• Has a history of, or currently has, an acquired or primary (congenital)immunodeficiency;

• Has had prior anti-cancer treatment with chemotherapeutic agents or immunemodulating agents within <4 weeks or 5 half-lives, whichever is shorter, prior tothe first dose of study drug.

• Has received a live vaccine within 30 days of first dose of study drug;

• Has had or has planned major surgery within 2 weeks of the first dose of study drug;

• Inability to swallow an oral dose of a medication (eg, oral capsules)

• Is taking medications that are considered strong inducers or inhibitors of CYP2C8 orCYP3A4/5, P-glycoprotein (P-gp), breast cancer resistant protein (BCRP), orsensitive substrates of P-gp and BCRP (Appendix C) that cannot be discontinued atleast 1 week prior to first dose of study drug and for the duration of the study.

• Is taking drugs that modify gastric pH, such as proton-pump inhibitors (PPIs) or H2blockers. Antacids such as calcium carbonate or aluminum hydroxide-based productsare permitted.