Inclusion Criteria:

          -  Patients 18 years of age and older with Hodgkin Lymphoma who have received auto-HSCT
             in the previous 45-120 days.

          -  Complete response (CR), partial response (PR) or stable disease (SD) to salvage
             therapy prior to ASCT.

          -  High risk of residual HL post-ASCT, as determined by 1 of the following:

               -  Positive positron emission tomography (PET) scan defined by the Deauville scale
                  3-4 and within 2 months of start of high dose chemotherapy prior to ASCT

               -  Refractory to frontline therapy

               -  Relapse <12 months after frontline therapy

               -  Relapse ≥12 months after frontline therapy with extra-nodal disease

          -  Eastern Cooperative Oncology Group (ECOG) Performance Status score of 0 - 1.

          -  Adequate hematologic function defined as all of the following:

               -  Absolute neutrophil count (ANC) ≥1000/μL

               -  Hemoglobin (Hgb) ≥8 g/dL (transfusions to reach this point are not permitted)

               -  Platelets ≥50,000/μL (transfusion is not permitted)

          -  Adequate liver function defined as all of the following:

               -  Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2.5 x the
                  upper limit of normal (ULN)

               -  Total bilirubin ≤1.5 x ULN (unless the patient has Grade 1 bilirubin elevation
                  due to Gilbert's disease or a similar syndrome involving slow conjugation of
                  bilirubin)

          -  Adequate renal function defined as serum creatinine ≤1.5 mg/dL (133 μmol/L).

          -  Females of childbearing potential must have a negative serum or urine pregnancy test
             result within 72 hours prior to the first dose of nivolumab and must agree to follow
             instructions for method(s) of contraception for the duration of treatment with
             nivolumab and for 7 months following their last dose of study drug. Females of
             non-childbearing potential are those who are postmenopausal greater than 1 year or who
             have had a bilateral tubal ligation or hysterectomy.

          -  Male patients with female partners of childbearing potential and women patients of
             childbearing potential are required to use two forms of acceptable contraception,
             including one barrier method, during their participation in the study and for 7 months
             following last dose of study drug. Male patients must also refrain from donating sperm
             during their participation in the study and for 7 months following last dose of study
             drug.

        Exclusion Criteria:

          -  Patients that have received an allogenic transplant.

          -  Post-ASCT or current therapy with other anti-neoplastic or investigational agents.

          -  Best clinical response of progressive disease prior to ASCT.

          -  Patients with any autoimmune disease or a history of autoimmune disease. Patients with
             vitiligo, type I diabetes mellitus, residual hypothyroidism due to autoimmune
             condition only requiring hormone replacement, psoriasis not requiring systemic
             treatment, or conditions not expected to recur in the absence of an external trigger
             are permitted to enroll.

          -  Any condition requiring systemic treatment with corticosteroids (> 10 mg daily
             prednisone equivalents) or other immunosuppressive medications within 14 days prior to
             first dose of study drug. Inhaled steroids and adrenal replacement steroid doses > 10
             mg daily prednisone equivalents are permitted in the absence of active autoimmune
             disease.

          -  Use of a study drug ≤ 21 days or 5 half-lives (whichever is shorter) prior to the
             first dose of nivolumab. For study drugs for which 5 half-lives is ≤21 days, a minimum
             of 10 days between termination of the study drug and administration of nivolumab is
             required.

          -  Wide field radiotherapy (including therapeutic radioisotopes such as strontium 89)
             administered ≤28 days or limited field radiation for palliation ≤7 days prior to
             starting study drug or has not recovered from side effects of such therapy.

          -  Major surgical procedures ≤28 days of beginning study drug, or minor surgical
             procedures ≤7 days. No waiting required following port-a-cath placement.

          -  Previously untreated brain metastases. Patients who have received radiation or surgery
             for brain metastases are eligible if therapy was completed at least 2 weeks prior to
             study entry and there is no evidence of central nervous system disease progression,
             mild neurologic symptoms, and no requirement for chronic corticosteroid therapy.

          -  Pregnant or lactating

          -  Acute or chronic liver, renal, or pancreatic disease.

          -  Uncontrolled diabetes mellitus. Patients with Type II diabetes are eligible if they
             require only oral hypoglycemic agents.

          -  Any of the following cardiac diseases currently or within the last 6 months:

               -  Left Ventricular Ejection Fraction (LVEF) <45% as determined by Multiple Gated
                  Acquisition (MUGA) scan or echocardiogram (ECHO)

               -  QTc interval >480 ms on screening electrocardiogram (ECG)

               -  Unstable angina pectoris

               -  Congestive heart failure (New York Heart Association (NYHA) ≥ Grade 2

               -  Acute myocardial infarction

               -  Conduction abnormality not controlled with pacemaker or medication

               -  Significant ventricular or supraventricular arrhythmias (patients with chronic
                  rate- controlled atrial fibrillation in the absence of other cardiac
                  abnormalities are eligible)

               -  Valvular disease with significant compromise in cardiac function

          -  Inadequately controlled hypertension (i.e., systolic blood pressure [SBP] >180 mmHg or
             diastolic blood pressure (DBP) >100 mmHg) (patients with values above these levels
             must have their blood pressure (BP) controlled with medication prior to starting
             treatment).

          -  Serious active infection at the time of treatment, or another serious underlying
             medical condition that would impair the ability of the patient to receive protocol
             treatment.

          -  Known diagnosis of human immunodeficiency virus, hepatitis B, or hepatitis C. Testing
             at baseline is not required.

          -  Presence of other active cancers, or history of treatment for invasive cancer ≤5
             years. Patients with Stage I cancer who have received definitive local treatment and
             are considered unlikely to recur are eligible. All patients with previously treated in
             situ carcinoma (i.e., non-invasive) are eligible, as are patients with history of
             non-melanoma skin cancer.

          -  Psychological, familial, sociological, or geographical conditions that do not permit
             compliance with the protocol.