Magrolimab Monotherapy or Magrolimab in Combination With Azacitidine in Participants With Hematological Malignancies

Key Inclusion Criteria:

* Meets the criteria below for the appropriate cohort:

1. Relapsed/Refractory Cohorts: Pathologically confirmed relapsed or refractory (primary refractory and/or relapsed refractory) AML or confirmed intermediate, high, or very high risk MDS that is relapsed, refractory or intolerant to conventional therapy
2. Treatment-naive/ Unfit Cohorts: Previously untreated individuals with histological confirmation of AML who are ineligible for treatment with a standard cytarabine and anthracycline induction regimen; or previously untreated individuals with intermediate, high, or very high risk MDS. Prior and concurrent therapy with hydroxyurea, oral etoposide, erythroid and/or myeloid growth factors is allowed.
3. Rollover Cohort: Individuals on active magrolimab therapy on the Phase 1 AML (SCI-CD47-002; NCT02678338) trial who are deriving clinical benefit by Investigator assessment
4. RBC transfusion dependent low risk MDS cohort: Transfusion-dependent MDS individuals who are very low or low risk by IPSS-R with previous treatment with an erythroid stimulating agent or lenalidomide.
* White blood cell (WBC) count ≤ 20 x 10\^3/mcL
* Adequate performance status and hematological, liver, and kidney function

Key Exclusion Criteria:

* Prior treatment with CD47 or signal regulatory protein alpha (SIRPα) targeting agents (with exception of magrolimab for individuals in the Rollover cohort).
* Treatment-naive/Unfit Cohorts Only: Any prior anti-leukemic therapy (excluding hydroxyurea or oral etoposide), prior treatment with hypomethylating agents and/or low dose cytarabine.
* Acute promyelocytic leukemia.
* Known inherited or acquired bleeding disorders.
* Previous allogeneic hematopoietic stem cell transplant within 6 months prior to enrollment, active graft versus host disease (GVHD), or requiring transplant-related immunosuppression.
* Clinical suspicion of active central nervous system (CNS) involvement by leukemia
* Known active or chronic hepatitis B or C infection or HIV
* Pregnancy or active breastfeeding

Note: Other protocol defined Inclusion/Exclusion criteria may apply.