Study to Compare Pharmacokinetics, Efficacy, Safety, and Immunogenicity of MB11 Versus EU-/US-Opdivo® in Subjects With Previously Untreated Advanced [Unresectable or Metastatic] Melanoma

This study is comparing a biosimilar version of nivolumab (called MB11) against the original branded nivolumab (Opdivo) as first-line treatment for advanced melanoma that cannot be removed surgically. A biosimilar is essentially a generic version of a biologic drug — the study is confirming it works the same way. **You may be eligible if...** - You are 18 or older (or the legal age of adulthood in your country) - You weigh at least 50 kg - You have confirmed advanced (Stage III or IV) melanoma that has not been treated before - Your overall health score (ECOG) is 0 or 1 - Your expected life expectancy is at least 3 months **You may NOT be eligible if...** - You have had prior immunotherapy as adjuvant or neoadjuvant treatment for melanoma - You have active autoimmune disease requiring treatment - You have brain metastases that are untreated or recently treated Talk to your doctor to see if this trial is right for you.