Re-registration Eligibility Criteria (for patients who crossover from arm 1 nivolumab alone to dual agent nivolumab and ipilimumab upon progression)
History of allergic reactions attributed to compounds of similar chemical or biologic composition to ipilimumab, nivolumab, or other agents used in study, or history of severe hypersensitivity reaction to any monoclonal antibody
Known sensitivity to or history of allergic reactions attributed to compounds of similar chemical or biologic composition entinostat, nivolumab, or ipilimumab; history of severe hypersensitivity reaction to any monoclonal antibody
Patients must not have any known allergy or reaction to any component of the nivolumab and ipilimumab formulations
Patients must not have prior history of allergy or known hypersensitivity to nivolumab or ipilimumab