RFS is defined as the time between the date of randomization and the first date of documented recurrence (local, regional, distant, new primary melanoma) or death due to any cause, whichever occurs first.

All Randomized Participants

OS is defined as the time between the date of randomization and the date of death due to any cause.

All Randomized Participants

DMFS is defined as the time between the date of randomization and the date of first distant metastasis or date of death due to any cause, whichever occurs first.

All Randomized Participants with Resected Stage 3/4a/4b Melanoma at study entry

PFS2 defined as time from randomization to second recurrence/objective disease progression on next-line systemic therapy per investigator, or death from any cause, whichever occurs first.

All Randomized Participants

Safety related events encompass the following measures: Adverse events (AEs), Serious AEs, AEs leading to discontinuation, Drug-Related AEs and Deaths.

An AE is defined as any new untoward medical occurrence or worsening of a pre-existing medical condition in a clinical investigation participant administered study treatment that does not necessarily have a causal relationship with this treatment.

An SAE is an AE which:

• Results in death
• Is life threatening
• Requires hospitalization
• Results in persistent or significant disability/incapacity
• Is a congenital anomaly/birth defect
• Is an important medical event

All Treated Population

Select AEs will be reported as AEs per organ class.

Organ classes which will be reported:

• Gastrointestinal
• Hepatic
• Pulmonary
• Renal
• Skin
• Hypersensitivity/Infusion reaction

All Treated Population

Immune-mediated adverse events are AEs consistent with an immune-mediated mechanism or immune-mediated component for which non-inflammatory etiologies (eg, infection or tumor progression) have been ruled out. IMAEs can include events with an alternate etiology which were exacerbated by the induction of autoimmunity.

All Treated Population

Immune-mediated adverse events are AEs consistent with an immune-mediated mechanism or immune-mediated component for which non-inflammatory etiologies (eg, infection or tumor progression) have been ruled out. IMAEs can include events with an alternate etiology which were exacerbated by the induction of autoimmunity.

All Treated Population

Number of participants with laboratory abnormalities in specific thyroid tests.

All Treated Participants with at least one on treatment TSH measurement