A First Time in Human (FTIH) Study of GSK3745417 Administered to Participants With Advanced Solid Tumors

Exclusion Criteria

• •Active autoimmune disease that has required systemic disease modifying or immunosuppressive treatment within the last 2 years.
• •Concurrent medical condition requiring the use of systemic immunosuppressive treatment within 28 days before the first dose of study treatment.
• •Current unstable liver or biliary disease.
• •History of vasculitis at any time prior to study treatment.
• •Evidence or history of significant active bleeding or coagulation disorder.
• •Active infection requiring systemic treatment, known human immunodeficiency virus infection, or positive test for hepatitis B surface antigen or hepatitis C.
• •QT duration corrected for heart rate by Fridericia's formula (QTcF) more than (\>)450 milliseconds (msec) or QTcF \>480 msec for participants with bundle branch block.
• •Recent history (within the past 6 months) of acute diverticulitis, inflammatory bowel disease, intra-abdominal abscess, or gastrointestinal obstruction.
• •Recent history of allergen desensitization therapy within 4 weeks of starting study treatment.
• •History or evidence of cardiovascular (CV) risk
• •Recent (within the past 6 months) history of symptomatic pericarditis.
• •History of idiopathic pulmonary fibrosis, interstitial lung disease, or organizing pneumonia, or evidence of active, non-infectious pneumonitis.
• •History of (non-infectious) pneumonitis that required steroids or current pneumonitis.
• •Recent history (within 6 months) of uncontrolled symptomatic ascites or pleural effusions.
• •Prior treatment with the following agents:
• •1. Stimulator of Interferon Genes (STING) agonist at any time.
• •2. Anticancer therapy or investigational therapy or used an investigational device within 28 days or 5 half-lives of the drug, whichever is shorter.
• •3. Checkpoint inhibitors, including Programmed death receptor-1 (PD-1), Programmed death Ligand-1 (PD-L1), PD-L2 and Cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors within 28 days.
• •4. Prior radiation therapy: permissible if at least 1 non-irradiated measurable lesion is available for assessment according to RECIST version 1.1 or if a solitary measurable lesion was irradiated, objective progression is documented.
• •Pregnant and/or breast feeding participants or those who plan to become pregnant and/or breastfeed.
• •Receipt of any live vaccine within 30 days of the start of study treatment.
• •Prior allogeneic or autologous bone marrow transplantation or other solid organ transplantation.
• •Major surgery less than or equal to (\<=)28 days before the first dose of study treatment. Participants must have also fully recovered from any surgery (major or minor) and/or its complications before initiating study treatment.
• •Participants with signs/symptoms suggestive of Coronavirus Disease-2019 (COVID-19) within 14 days of study entry, or with known exposure to COVID-19 within 14 days prior to study entry.
• •Participants are excluded from Part 2A of the study if they have known hypersensitivity to dostarlimab or associated excipients.