Administration of a live, attenuated vaccine within weeks before Cycle , Day Patients are ineligible if administration of a live, attenuated vaccine within weeks before randomization Administration of live vaccine within weeks prior to study entry Treatment with a live, attenuated vaccine within weeks before initiation of study treatment, or anticipation of need for such a vaccine during the course of the study Administration of a live, attenuated vaccine within days prior to randomization or anticipation that such vaccine will be required during the study. Patients must agree not to receive live, attenuated influenza vaccine (e.g., FluMist) within days prior to randomization, during treatment or within months following the last dose of atezolizumab/placebo. Administration of a live attenuated vaccine within weeks prior to initiation of study treatment or anticipation of need for such a vaccine during the study Administration of a live, attenuated vaccine within weeks before Cycle Day Treatment with a live, attenuated vaccine within weeks prior to initiation of study treatment, or anticipation of need for such a vaccine during the course of the study Treatment with therapeutic oral or intravenous (IV) antibiotics; or with a live, attenuated vaccine; or systemic immunosuppressive medication Administration of a live, attenuated vaccine within weeks prior to Cycle Day or at any time during the study and for at least months after the last dose of study drug Receipt of a live, attenuated vaccine within weeks prior to randomization or anticipation that such a live, attenuated vaccine will be required during the study Administration of a live vaccine within weeks prior to study entry Receipt of a live, attenuated vaccine within weeks prior to randomisation or anticipation that a live, attenuated vaccine will be required during atezolizumab/placebo treatment or within months after the last dose of atezolizumab/placebo Administration of a live, attenuated vaccine within weeks before cycle , day or anticipation that such a live attenuated vaccine will be required during the study Any live, attenuated vaccine within days prior to the first day of treatment or during study treatment, or unwillingness to avoid live, attenuated vaccines within days following the last dose of atezolizumab Administration of a live vaccine within weeks prior to start of protocol therapy Administration of a live, attenuated vaccine within weeks for first study treatment Live, attenuated vaccine within days prior to the first dose of protocol therapy Patients who have received a live attenuated vaccine =< days prior to registration are not eligible Has received a live attenuated vaccine within days prior to enrolling in the study. Administration of a live, attenuated vaccine within weeks prior to enrollment or anticipation that such a live attenuated vaccine will be required during the study Received a live attenuated vaccine within days of first study dose, unable to take oral medications Administration of a live, attenuated vaccine within weeks prior to randomization or anticipation that such vaccine will be required during the study\r\n* Patients must agree not to receive live, attenuated influenza vaccine (e.g., FluMist) within weeks prior to randomization, during treatment or within months following the last dose of atezolizumab/placebo Live, attenuated vaccine within days prior to day of protocol therapy Administration of a live, attenuated vaccine within weeks of Cycle , Day or anticipation that such a live attenuated vaccine will be required during the study Patients who receive a live attenuated vaccine =< days prior to registration are not eligible Administration of a live, attenuated vaccine within weeks of the start of treatment or anticipation that such a live, attenuated vaccine will be required during the study Administration of a live, attenuated vaccine within weeks before first dosing or during the study. Has received live, attenuated vaccine within days prior to Study Day Patient who requires live vaccine administration Subject has received a live, attenuated vaccine within days prior to Cycle Day ; Receipt of a live, attenuated vaccine within weeks prior to randomization or anticipation that such a live, attenuated vaccine will be required during the study Has received live, attenuated vaccine within days prior to Study Day Treatment with a live vaccine or a live, attenuated vaccine (e.g., nasal spray of live attenuated influenza vaccine or FluMist) within weeks prior to initiation of study drug or anticipation that such treatment will be required during the study or within months after the final dose of study drug Treatment with a live, attenuated vaccine within weeks prior to initiation of study treatment, or anticipation of need for such a vaccine during the course of the study, or up to months following the anticipated last dose of atezolizumab Administration of a live, attenuated vaccine within weeks prior to enrollment Live attenuated vaccine within weeks of study drug Administration of a live, attenuated vaccine within weeks before Cycle , Day or anticipation that such a live, attenuated vaccine will be required during the study Administration of attenuated vaccine within weeks before enrollment Vaccination with a live virus vaccine or live attenuated vaccine within days prior to DC Administration of a live, attenuated vaccine within weeks prior to randomization Administration of a live, attenuated vaccine within weeks before Cycle , Day Administration of a live, attenuated vaccine within weeks before Cycle Day Exclusion Criteria Unique to Cobimetinib: Administration of a live, attenuated vaccine within days before first dose of study treatment. Administration of a live, attenuated vaccine within weeks before cycle , day or anticipation that such a live, attenuated vaccine will be required during the study Administration of a live, attenuated vaccine within weeks before Cycle , Day or anticipation that such a live attenuated vaccine will be required during the study Administration of a live/attenuated vaccine within weeks prior to the first dose of study treatment, within months following the administration of the last dose of study drug, or anticipation that such a live/attenuated vaccine will be required during the study Administration of live, attenuated vaccine within weeks before the start of treatment (day ) and throughout the study Administration of a live, attenuated vaccine within weeks before cycle , day or anticipation that such a live, attenuated vaccine will be required during the study Administration of live, attenuated vaccine within weeks before the start of treatment (day ) and throughout the study Any plan to receive a live attenuated vaccine during study treatment Administration of a live, attenuated vaccine within weeks before Cycle , Day or anticipation that such a live attenuated vaccine will be required during the study Administration of a live, attenuated vaccine within weeks before Cycle , Day or anticipation that such a live attenuated vaccine will be required during the study Administration of a live, attenuated vaccine within weeks for first study treatment Administration of a live, attenuated vaccine within weeks before Cycle , Day or anticipation that such a live attenuated vaccine will be required during the study Live attenuated vaccine within weeks prior to first day of study treatment Receipt of a live, attenuated vaccine within weeks prior to initiation of study drug (cycle , day [CD]) or anticipation that such a live, attenuated vaccine will be required during the study Administration of a live, attenuated vaccine within days before Day or anticipation that such a live attenuated vaccine will be required during the study Administration of a live, attenuated vaccine within weeks before Cycle , Day