Study of the Safety and Effectiveness of GSK6097608 in Participants With Advanced Solid Tumors

Inclusion Criteria:

• Adults 18 years of age or older (or >=20 years of age in Arm-A Japan, Arm-D Japan,Arm E-Japan, Arm F-Japan, and Arm G-Japan)

• Female participants of childbearing potential must agree to use a highly effectiveform of contraception

• Histological or cytological documentation of locally advanced, recurrent, ormetastatic solid malignancy. Enrollment in PK/PD cohorts will be restricted toparticipants with histologically or cytologically confirmed diagnosis of 1 or moreof the following: non-small-cell lung cancer (NSCLC), head and neck squamous cellcarcinoma (HNSCC), endometrial cancer (EC), colorectal cancer (CRC) (includingspecified molecular subtypes of these) or an alternative immunogenic tumor type withmedical monitor approval

• Disease that has progressed after standard therapy for the specific tumor type, orfor which standard therapy has proven to be ineffective, intolerable, or isconsidered inappropriate, or if no further standard therapy exists

• Participants in a PK/PD cohort (Arms A, B, E and F) must provide fresh tumorbiopsies. Biopsies are not required from participants enrolled in Arm D, Arm E, (non-PK/PD cohorts only), Arm F (non-PK/PD cohort only), Arm G or any participantenrolled in mainland China

• Eastern cooperative oncology group (ECOG) performance status (PS) 0 to 1

• Life expectancy of at least 12 weeks

• Adequate organ function as determined by laboratory assessments

• Adequate cardiac ejection fraction as measured by echocardiogram

• Arm A-Japan, Arm D-Japan, Arm E-Japan, Arm F-Japan, and Arm G-Japan only: lives inJapan and is racially Japanese, defined as all biological grandparents beingJapanese

• Arm A-China, Arm B-China, Arm D-China, Arm E-China and Arm F-China only (excludingPK/PD cohorts in Arm E and Arm F): is of Chinese descent and lives in China

• Arm D, Arm E, Arm F, and Arm G only: has been deemed suitable for assigned treatmentbased on assessment by the investigator

Exclusion Criteria:

• Prior anti-cancer treatment including investigational agents, immune checkpointinhibitors, chemotherapy, targeted therapy, and biological therapy: within 4 weeksor 5 half-lives of the drug, whichever is shorter

• Prior allogenic or autologous bone marrow transplantation or other solid organtransplantation

• Toxicity from previous anticancer treatment, including; greater than or equal to (>=) Grade 3 immune-mediated toxicity considered related to prior immunotherapy andthat led to treatment discontinuation; or toxicity related to prior treatment thathas not resolved; or history of myocarditis of any grade during a previous treatmentwith immunotherapy

• Known additional malignancy that progressed or required active treatment within thelast 2 years

• Uncontrolled or symptomatic central nervous system (CNS) metastases and/orcarcinomatous meningitis

• Active autoimmune disease that has required systemic disease-modifying orimmunosuppressive treatment within the last 2 years

• Concurrent medical condition requiring the use of systemic immunosuppressivetreatment

• Cirrhosis or current unstable liver or biliary disease per investigator assessment

• Active infection requiring systemic treatment, known human immunodeficiency virusinfection, or positive test for hepatitis B surface antigen (HBsAg) or hepatitis Cvirus (HCV)

• Prolonged QT as measured by electrocardiogram

• Allergen desensitization therapy within 4 weeks of starting study intervention

• History of hypersensitivity to any of the study interventions or their excipients

• Has a history or evidence of cardiac abnormalities within the 6 months prior toenrolment

• Recent history (within 6 months) of uncontrolled symptomatic ascites or pleuraleffusions

• History of idiopathic pulmonary fibrosis; interstitial lung disease; organizingpneumonia; noninfectious pneumonitis that required steroids, or evidence of active,noninfectious pneumonitis

• Pregnant or lactating woman

• Receipt of live vaccine within 30 days of the start of study intervention

• Receipt of transfusion of blood products or administration of colony-stimulatingfactors within 14 days before the first dose of study intervention

• Major surgery less than 4 weeks before the first dose of study intervention

• Known drug or alcohol abuse