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

The primary objectives of this study are:

* To confirm the safety and tolerability of magrolimab monotherapy in a relapsed/refractory (R/R) acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) population, and of magrolimab in combination with azacitidine in previously untreated participants with AML or MDS and participants with R/R AML and MDS
* To evaluate the efficacy of magrolimab monotherapy in R/R AML/MDS, and of magrolimab in combination with azacitidine in previously untreated participants with AML/MDS, or R/R AML/MDS as measured by complete remission (CR) rate for participants with AML and higher-risk MDS, and duration of complete response for participants with AML and higher-risk MDS, and duration of CR for participants with AML and higher-risk MDS
* To evaluate the safety, tolerability, and efficacy of magrolimab monotherapy or combination with azacitidine in low-risk MDS participants as measured by red blood cell (RBC) transfusion independence rate


Eligibility Criteria:
Key Inclusion Criteria:

* Meets the criteria below for the appropriate cohort:

  * Relapsed/Refractory Cohorts: Pathologically confirmed relapsed or refractory (primary refractory and/or relapsed refractory) acute myeloid leukemia (AML) or confirmed intermediate, high, or very high risk myelodysplastic syndromes (MDS) that is relapsed, refractory or intolerant to conventional therapy.
  * 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.
  * 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.
  * RBC transfusion dependent low risk MDS cohort: Transfusion-dependent MDS individuals who are very low or low risk by Revised International Prognostic Scoring System (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 cluster of differentiation 47 (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.