A Study to Assess the Safety and Tolerability of Atezolizumab in Combination With Other Immune-Modulating Therapies in Participants With Locally Advanced or Metastatic Solid Tumors

Inclusion Criteria

• Inclusion Criteria: - Histologically or cytologically documented locally advanced or metastatic solid tumors meeting the following study drug-specific criteria: - Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1 - Life expectancy greater than or equal to (>/=) 12 weeks - Measurable disease, as defined by RECIST v1.1 - Adequate hematologic and end organ function as confirmed by laboratory results within 14 days prior to the first study treatment Inclusion criteria specific to Arm A: Atezolizumab+ Ipilimumab - Escalation stage: NSCLC participants - Mandatory biopsy cohort: NSCLC or melanoma atezolizumab - Prior atezolizumab-treated cohort: participants with NSCLC or melanoma previously treated with atezolizumab Inclusion criteria specific to Arm B: Atezolizumab+ Interferon alfa-2b - Escalation stage: RCC or melanoma participants - Expansion stage: RCC or melanoma participants - Mandatory biopsy cohort: RCC or melanoma participants - Prior immunotherapy-treated cohort: participants with RCC, NSCLC, or melanoma previously treated with programmed death-ligand 1 (PD-L1)/ Programmed death 1 (PD-1) Inclusion Criteria Specific to Arm C (Atezolizumab plus PEG-Interferon Alafa-2a): - Cohort 1: participants with RCC Inclusion Criteria Specific to Arm D (Atezolizumab plus PEG-Interferon Alfa-2a +Bevacizumab) - Cohort 1: participants with metastatic RCC with no prior line of systemic therapy for metastatic disease - Cohorts 2-3: disease progression during or after at least one previous systemic, anti-cancer treatment for locally advanced or metastatic non-squamous solid tumors; participants with sensitizing epidermal growth factor receptor (EGFR) mutations or anaplastic lymphoma kinase (ALK) rearrangements must have failed or are intolerant to prior treatment with EGFR or ALK inhibitors; participants with melanoma with actionable BRAF mutations (e.g., V600) must have failed or are intolerant to prior treatment with BRAF inhibitors Inclusion Criteria Specific to Arm E (Atezolizumab +Obinutuzumab) - R/M HNSCC participants with at least one prior line of systemic therapy Inclusion Criteria Specific to prior Anti-PD-L1/PD-1 Treated Cohorts: - No permanent discontinuation of atezolizumab or other immunotherapies due to a treatment-related adverse event - Recovery from all immunotherapy-related adverse events to Grade less than or equal to (≤) 1 or baseline at the time of consent Exclusion Criteria: General Medical Exclusions: - Pregnant and lactating women - Any approved anti-cancer therapy, including chemotherapy or hormonal therapy, within 3 weeks prior to initiation of study treatment, with the following exception: (1) hormone-replacement therapy or oral contraceptives; (2) tyrosine kinase inhibitors (TKIs) that have been discontinued greater than (>) 7 days prior to Cycle 1, Day 1, baseline scans must be obtained after discontinuation of prior TKIs - Investigational therapy within 28 days prior to initiation of study treatment - History of severe allergic, anaphylactic, or other hypersensitivity reactions to chimeric or humanized antibodies or fusion proteins - Known hypersensitivity or allergy to Chinese hamster ovary cell products or any component of the atezolizumab formulation - History of or active autoimmune disease - History of idiopathic pulmonary fibrosis (including pneumonitis), drug-induced pneumonitis, organizing pneumonia, risk of pulmonary toxicity, or evidence of active pneumonitis on screening chest computed tomography (CT) scan - Prior allogeneic bone marrow transplantation or prior solid organ transplantation - History of human immunodeficiency virus (HIV) - Participants with active hepatitis B - Participants with active hepatitis C - Participants with active tuberculosis - Participants with a history of confirmed progressive multifocal leukoencephalopathy - Any serious medical condition, physical examination finding, or abnormality in clinical laboratory tests that, in the investigator's judgment, precludes the participant's safe participation in and completion of the study Cancer-Specific Exclusions: - Active or untreated central nervous system (CNS) metastases, as determined by CT or magnetic resonance imaging (MRI) evaluation during screening and prior radiographic assessments - Spinal cord compression not definitively treated with surgery and/or radiation or previously diagnosed and treated spinal cord compression without evidence that disease has been clinically stable for >/= 2 weeks prior to screening - Leptomeningeal disease - Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures (once monthly or more frequently); participants with indwelling catheters are allowed. - Uncontrolled tumor-related pain - Uncontrolled hypercalcemia or symptomatic hypercalcemia requiring continued use of bisphosphonate therapy or denosumab - History of other malignancy within 2 years prior to screening, except for appropriately treated carcinoma in situ of the cervix, non-melanoma skin carcinoma, Stage I uterine cancer, localized prostate cancer treated with curative intent, ductal carcinoma in situ treated surgically with curative intent, or other cancers with a similar outcome Exclusion Criteria Related to Medications: - Prior treatment with cluster of differentiation 137 (CD137) agonists or immune checkpoint blockade therapies (Note: Participants enrolled in the prior anti-PD-L1/PD-1 treated cohorts with melanoma may have received prior anti-cytotoxic T-lymphocyte-associated protein 4 treatment or other immunotherapies) - Treatment with systemic immunostimulatory agents within four weeks or five half-lives of the drug, whichever is shorter, prior to Cycle 1, Day 1 - Treatment with systemic immunosuppressive medications within 2 weeks prior to Cycle 1, Day 1 (the use of inhaled corticosteroids and mineralocorticoids is allowed) Exclusion Criteria Specific to Interferon Alpha Therapy (Arms B-D): - History of depression, suicidal ideation or behavior, bipolar disorder, or psychosis - Hypersensitivity to interferon alpha or any component of the product Exclusion Criteria Specific to Bevacizumab (Arm D) - Inadequately controlled hypertension - Prior history of hypertensive crisis or hypertensive encephalopathy - Significant vascular disease within 6 months prior to Day 1 - History of hemoptysis - Evidence of bleeding diathesis or significant coagulopathy (in the absence of therapeutic anticoagulation) - History of tracheoesophageal fistula, gastrointestinal perforation, or intra-abdominal abscess within 6 months prior to Day 1 - Clinical signs or symptoms of gastrointestinal obstruction or requirement for routine parenteral hydration, parenteral nutrition, or tube feeding - Evidence of abdominal free air that is not explained by paracentesis or recent surgical procedure - Proteinuria, as demonstrated by urine dipstick or > 1.0 gram of protein in a 24-hour urine collection - Metastatic disease that involves major airways or blood vessels, or centrally located mediastinal tumor masses of large volume Exclusion Criteria Specific Obinutuzumab (Arm E) - Hypersensitivity to obinutuzumab - Prior treatment with obinutuzumab