Gemcitabine, Bendamustine, and Nivolumab in Patients With Relapsed or Refractory Classical Hodgkin Lymphoma

Inclusion Criteria: * Histologically documented classical Hodgkin lymphoma that is recurrent or refractory after standard chemotherapy. Core biopsies are acceptable if they contain adequate tissue for primary diagnosis and immunophenotyping. Bone marrow biopsies as the sole means of diagnosis are not acceptable. At least one biopsy-proven relapse is required for enrollment, but patients who have multiply relapsed disease do not require repeat biopsy if not clinically indicated * Prior treatment: patients must have relapsed or progressed after at least one prior therapy * Patients with relapsed or refractory disease following autologous stem cell transplantation are permitted. Due to the risk of treatment-refractory graft versus host disease (GVHD), patients who have previously completed an allogeneic transplant are excluded. * Patients may have received gemcitabine, bendamustine, or nivolumab in the past but may not have discontinued therapy due to toxicity felt to be related to that specific drug * Eastern Cooperative Oncology Group (ECOG) performance status 0-2 * Measurable disease must be present either on physical examination or imaging studies. Non-measurable disease alone is not acceptable * Measurable disease * Lesions that can be accurately measured in at least two dimensions as ≥ 1.0 x 1.0 cm by computerized tomography (CT), positron emission tomography (PET)/CT (positron emission tomography/CT), or magnetic resonance imaging (MRI). * If identified …