Trial Drug: Bendamustine

The purpose of this study is to compare efficacy of coformulated favezelimab/pembrolizumab (MK-4280A) with physician’s choice chemotherapy of bendamustine or gemcitabine in participants with PD-(L)1-refractory, relapsed or refractory classical Hodgkin Lymphoma. The study will also assess the safety and tolerability of coformulated favezelimab/pembrolizumab. The primary study hypotheses are that coformulated favezelimab/pembrolizumab is superior to physician’s choice chemotherapy with respect to progression-free survival (PFS) and overall survival (OS).