The percentage of participants who experienced at least 1 adverse event in the MedDRA Anaphylactic Reaction broad scope SMQ with onset on the day of or within 2 days after any study therapy infusion during the combination period (Part 1).

All treated participants

The percentage of participants who experienced at least 1 adverse event in the MedDRA Anaphylactic Reaction narrow scope SMQ with onset on the day of or within 2 days after any study therapy infusion during the combination period (Part 1).

All treated participants

The percentage of participants who experienced at least 1 adverse event of Grade 3 or higher, judged to be related to study treatment by the investigator, with onset on or after the first dose of study treatment and within 30 days of the last dose of study treatment. Evaluated using Common Terminology Criteria for Adverse Events (NCI CTCAE) version 4.0 criteria.

All treated participants

The percentage of participants who experienced at least 1 adverse event of Grade 3 or higher with onset on or after the first dose of study treatment and within 30 days of the last dose of study treatment. Evaluated using the NCI CTCAE version 4.0 criteria

All treated participants

The percentage of participants with a best overall response (BOR) of complete response (CR) or partial response (PR). The BOR is defined as the best response designation, as determined by the investigator, recorded between the date of randomization and the date of objectively documented progression per RECIST 1.1 or the date of first subsequent anti-cancer therapy, whichever occurs first. For participants without documented progression or subsequent therapy, all available response designations will contribute to the BOR assessment. Complete Response is defined as the disappearance of all target lesions. Any pathological lymph nodes (whether target or non-target) must have reduction in short axis to < 10mm. Partial Response is defined as at least a 30% decrease in the sum of diameters of target lesions, taking as reference the baseline sum diameters.

All treated participants

The time between the date of randomization and the first date of documented progression, or death due to any cause, whichever occurs first (per investigator). Participants who die without progression will be considered to have progressed on the date of their death. Participants who did not progress or die are censored on the date of their last evaluable tumor assessment. Participants with no on study tumor assessments and who did not die will be censored on their date of randomization. Participants who started anti-cancer therapy without a prior reported progression will be censored on the date of their last evaluable tumor assessment prior to the first subsequent anti-cancer therapy. Progression is defined as at least a 20% increase in the sum of diameters of target lesions. The sum must also demonstrate an absolute increase of at least 5 mm. (Note: the appearance of one or more new lesions is also considered progression)

All treated participants

Serum concentration-time data of nivolumab and ipilimumab administered as a fixed ratio combination to that of sequentially administered nivolumab and ipilimumab is summarized prior to the next dose (predose). 1 Cycle = 3 weeks

All treated participants with available serum time-concentration data

Serum concentration-time data of nivolumab and ipilimumab administered as a fixed ratio combination to that of sequentially administered nivolumab and ipilimumab is summarized at the end of infusion (EOI). 1 Cycle = 3 weeks

All treated participants with available serum time-concentration data