Study to Compare Adjuvant Immunotherapy of Bempegaldesleukin Combined With Nivolumab Versus Nivolumab After Complete Resection of Melanoma in Patients at High Risk for Recurrence

Inclusion Criteria:

* Male or female patients, age 12 years or older at the time of signing the informed consent form (age 18 years or older where local regulations, countries, and/or institutional policies do not allow for patients \< 18 years of age (adolescents) to participate). In regions where adolescents are not allowed to participate in the study due to age restrictions, enrolled patients must be ≥ 18 years of age.
* Histologically confirmed Stage IIIA (LN metastasis \> 1 mm), IIIB/C/D, or IV (M1a/b/c/d) cutaneous melanoma by AJCC (8th edition) at study entry that has been completely surgically resected within 12 weeks prior to randomization.
* Tumor tissue available from biopsy or resected disease must be provided to central laboratory for PD-L1 status analysis. Must have PD-L1 expression classification for stratification purposes.
* Disease-free status documented by a complete physical examination and imaging studies within 28 days prior to randomization.

Exclusion Criteria:

* History of ocular/uveal melanoma or mucosal melanoma.
* Active, known or suspected autoimmune disease. Patients with Type I diabetes mellitus, hypothyroidism only requiring hormone replacement, skin disorders not requiring systemic treatment, or conditions not expected to recur in the absence of an external trigger are permitted to enroll.
* Conditions requiring systemic treatment with either corticosteroids (\> 10 mg daily prednisone equivalent) or other immunosuppressive medications within 14 days of randomization. Inhaled or topical steroids, and adrenal replacement steroid doses \> 10 mg daily prednisone equivalent, are permitted in the absence of active autoimmune disease.
* Prior therapy for melanoma except surgery for the melanoma lesion(s) and/or adjuvant radiation therapy for central nervous system lesions.
* Prior therapy with interferon, talimogene laherparepvec (Imylgic®), interleukin-2 (IL-2) directed therapy, anti-PD-1, anti-PD-L1, anti-PD-L2, anti-CD137, or anti-cytotoxic T lymphocyte-associated protein 4 antibody (including ipilimumab or any other antibody or drug specifically targeting T cell co-stimulation or checkpoint pathways).
* Prior malignancy active within the previous 3 years except for locally potentially curable cancers that have been apparently cured.