Inclusion Criteria:

          -  Age ≥ 18 years

          -  Eastern Cooperative Oncology Group (ECOG) performance status 0 to 1

          -  Biopsy proven relapsed or refractory cHL

          -  Prior treatment with at least two systemic therapies

          -  Metabolically active measurable disease by PET imaging per the 2014 Lugano criteria

          -  Hemoglobin ≥ 9.0 g/dL

          -  Absolute neutrophil count ≥ 1,000 cells/μL

          -  Platelet count ≥ 75,000 cells/μL

          -  Creatinine clearance > 40 mL/min per the Cockroft-Gault formula

          -  Total bilirubin < 1.5 x upper limit of normal (ULN) (or < 3.0 x ULN and primarily
             unconjugated in subjects with a history of Gilbert's syndrome)

          -  Negative urine or serum pregnancy test within 30 days of enrollment and within 72
             hours before the first administration of magrolimab for women of childbearing
             potential

          -  Women of childbearing potential must be willing to use at least 1 highly effective
             method of contraception during the study and continue for 4 months after the last dose
             of magrolimab

          -  Male subjects who are sexually active with a woman of childbearing potential and who
             have not had vasectomies must be willing to use a barrier method of contraception
             during the study and for 4 months after the last dose of magrolimab

          -  Ability to understand and the willingness to sign the written IRB approved informed
             consent document

          -  Must be willing and able to comply with the clinic visits and procedures outlined in
             the study protocol

        Exclusion Criteria:

          -  Prior treatment with antibodies targeting PD 1, PD L1, CD47, or Signal regulatory
             protein α (SIRPα)

          -  Prior allogeneic hematopoietic cell transplantation

          -  Systemic autoimmune disorder on chronic immunosuppression (defined as ≥ 10 mg of
             prednisone daily)

          -  History of hemolytic anemia, autoimmune thrombocytopenia, or Evan's syndrome within
             the last 3 months

          -  Second malignancy not in complete remission for at least 1 year, excluding fully
             resected non melanoma skin cancer or localized prostate cancer

          -  Pregnant or breast feeding

          -  HIV or hepatitis B or C infection with active viral replication by PCR

          -  Second malignancy not in complete remission for at least 1 year, excluding fully
             resected non-melanoma skin cancer or localized prostate cancer

          -  Active cardiac disease including unstable angina, decompensated congestive heart
             failure, or severe uncontrolled conduction abnormalities

          -  Significant medical conditions, as assessed by the investigators and IND holder, that
             would substantially increase the risk benefit ratio of participating in the study

          -  History of psychiatric illness or substance abuse likely to interfere with ability to
             comply with protocol requirements