Study of GS-1811 Given Alone or With Zimberelimab in Adults With Advanced Solid Tumors

Key Inclusion Criteria:

   - Disease:

      - Part A: Individuals with histologically or cytologically confirmed advanced solid
      tumors who have received, been intolerant to, or been ineligible for all
      treatment known to confer clinical benefit.

      - Part B: Individuals with histologically or cytologically confirmed select
      indications who have received, been intolerant to, or been ineligible for all
      treatment known to confer clinical benefit.

      - Part C: Individuals with histologically or cytologically confirmed advanced solid
      tumors who have received, been intolerant to, or been ineligible for all
      treatments known to confer clinical benefit or whose disease is indicated for
      anti- programmed cell death protein 1 or programmed cell death ligand 1 (PD-[L]1)
      monoclonal antibody monotherapy.

      - Part D: Individuals with pathologically confirmed select advanced solid tumors.

      - Part E: Individuals with pathologically confirmed select advanced solid tumors.
      Participants must have received, have been intolerant to, or have been ineligible
      for all treatment known to confer clinical benefit.

      - Part F: Individuals with pathologically-confirmed select advanced solid tumors.
      Participants must have received, have been intolerant to, or have been ineligible
      for all treatments known to confer clinical benefit; or, for participants who
      will undergo combination therapy, have disease which is indicated for
      anti-PD-(L)1 mAb monotherapy.

   - Measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1

   - Eastern Cooperative Oncology Group (ECOG) performance status 0, 1, or 2 for
   individuals in Parts A, B, and C, and 0 or 1 for individuals in Parts D, E, and F.

   - Adequate organ function.

   - Male individuals and female individuals of childbearing potential who engage in
   heterosexual intercourse must agree to use methods of contraception.

   - Tissue requirement:

      - Parts A, C, D, E and F: Must provide pre-treatment adequate tumor tissue sample
      prior to enrollment.

      - Part B and select participants in Parts C and F: Must have fresh pre-treatment
      and on-treatment biopsies for biomarker analysis.

Key Exclusion Criteria:

   - Concurrent anticancer treatment.

   - Any anti-cancer therapy, whether investigational or approved, within protocol
   specified time prior to initiation of study including: immunotherapy or biologic
   therapy (< 28 days), chemotherapy (< 21 days), targeted small molecule therapy (< 14
   days), hormonal therapy or other adjunctive therapy (< 14 days) or radiotherapy (< 21
   days).

   - Any prior CCR8 directed therapy.

   - Prior allogeneic tissue/solid organ transplantation, including allogeneic stem cell
   transplantation. Exception: prior corneal transplant without requirement for systemic
   immunosuppressive agents is allowed.

   - Concurrent active malignancy other than nonmelanoma skin cancer, curatively resected
   carcinoma in situ, localized prostate cancer, or superficial bladder cancer after
   undergoing potentially curative therapy with no evidence of disease. Individuals with
   other previous malignancies are eligible if disease-free for > 2 years.

   - History of intolerance, hypersensitivity, or treatment discontinuation due to severe
   immune-related adverse events (irAEs) on prior immunotherapy.

   - History of autoimmune disease or active autoimmune disease requiring systemic
   treatment within 2 years.

   - History of pneumonitis, interstitial lung disease, or severe radiation pneumonitis
   (excluding localized radiation pneumonitis).

   - Active and clinically relevant bacterial, fungal, or viral infection that is not
   controlled or requires IV antibiotics.

   - Active hepatitis B virus (HBV) and/or hepatitis C virus (HCV), and/or human
   immunodeficiency virus (HIV).

   - Positive serum pregnancy test or breastfeeding female.

   - Live vaccines within 30 days prior to first dose.

   - Significant cardiovascular disease.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.