Inclusion Criteria:

          -  Documented confirmation of acute myeloid leukemia (AML) according to the World Health
             Organization (WHO) criteria, previously untreated. [OR]

          -  Documented diagnosis of previously untreated de novo myelodysplastic syndrome (MDS)
             according to the 2017 WHO classification with presence of < 20% bone marrow blasts per
             marrow biopsy/aspirate.

          -  Participants with documented MDS must meet the following disease activity criteria:

               -  Overall revised international prognostic scoring system (IPSS-R) score > 3
                  (intermediate, high, or very high);

               -  Eastern cooperative oncology group (ECOG) performance status of 0 to 2;

               -  Hematopoietic stem cell transplant (HSCT) eligible with no pre-arranged HSCT at
                  the time of Study Day 1, or HSCT ineligible without plan for HSCT at the time of
                  Study Day 1.

          -  Participants with documented AML and considered ineligible for induction therapy
             defined by the following:

               -  75 years of age; [OR]

               -  18 to 74 years of age with at least one of the following comorbidities:

                    -  Eastern cooperative oncology group (ECOG) performance status of 2 to 3;

                    -  Cardiac history of congestive heart failure requiring treatment or ejection
                       fraction ≤ 50% or chronic stable angina;

                    -  Diffusion capacity of lung (DLCO) ≤ 65% or forced expiratory volume during
                       the first second (FEV1) ≤ 65%;

                    -  Creatinine clearance ≥ 30 mL/min to < 45 mL/min;

                    -  Moderate hepatic impairment with total bilirubin > 1.5 to ≤ 3.0 × upper
                       limit of normal (ULN);

                    -  Any other comorbidity that the physician judges to be incompatible with
                       intensive chemotherapy or the participant declines to receive intensive
                       chemotherapy.

        Exclusion Criteria:

          -  Participants with documented AML with acute promyelocytic leukemia and considered
             eligible for induction therapy.

          -  Participant with documented AML having prior diagnosis of:

               -  chronic myeloid leukemia with or without BCR-ABL1 translocation and AML with
                  BCR-ABL1 translocation;

               -  known active central nervous system involvement with AML.

        Participants with documented MDS having prior diagnosis of:

          -  Therapy-related MDS;

          -  MDS evolving from a pre-existing myeloproliferative neoplasm (MPN);

          -  MDS/MPN including chronic myelomonocytic leukemia, atypical chronic myeloid leukemia,
             juvenile myelomonocytic leukemia and unclassifiable MDS/MPN.

               -  History of allogeneic HSCT or solid organ transplantation.

               -  Previous exposure to azacitidine or venetoclax or anti-CD47 therapies.

               -  History of an active malignancy within the past 2 years prior to Screening, with
                  the exception of:

          -  Adequately treated carcinoma in situ of the cervix uteri or carcinoma in situ of the
             breast;

          -  Adequately treated basal cell carcinoma or localized squamous cell carcinoma of the
             skin;

          -  Asymptomatic prostate cancer without known metastatic disease and with no requirement
             for therapy;

          -  Previous malignancy confined and surgically resected (or treated with other
             modalities) with curative intent.

               -  Conditions that could interfere with drug absorption including but not limited to
                  short bowel syndrome.