Inclusion Criteria:

* Participant must be 18 years of age inclusive or older.
* Eastern Cooperative Oncology Group (ECOG) performance status 0-1.
* Participants with relapsed or refractory MM who have received at least 3 prior lines of therapy for MM, including PIs and IMiDs or at least 2 prior lines if at least one of these lines consisted of 2 or more multiagent regimens (eg, Induction regimen with autologous stem cell transplant followed by maintenance).
* RRMM with measurable disease:

* Serum M protein ≥0.5 g/dL measured using serum protein immunoelectrophoresis and/or
* Urine M protein ≥200 mg/24 hours measured using urine protein immunoelectrophoresis and/or
* Serum free light chain (sFLC) MM without measurable M protein in serum or urine per previous criteria (serum Ig free light chain ≥10 mg/dL and abnormal serum Ig kappa lambda free light chain ratio \<0.26 or \>1.65).
* Men or woman or childbearing potential should agree to use contraception.
* Substudy 01, 06: Anti-CD38 therapy naïve or prior exposure to such drugs with a wash out of at least 6 months after the last dose. "Exposure" is defined as at least 2 cycles of therapy.
* Substudies 02, 03: Anti-CD38 therapy naïve or prior exposure to such drugs without being refractory but with a wash out of at least 6 months after the last dose. "Refractory" is defined as progressing within 60 days of last dose of anti-CD38 targeting therapy.
* Substudy 04: Anti-CD38 and anti-B cell maturation antigen (BCMA) therapy prior exposed participants with RRMM.
* Substudy 05: Participants with RRMM with at least 2 cycles of prior exposure to anti-CD38 therapy. For participants to whom BCMA targeted therapy is available (ie, approved in their region and can be reimbursed), at least 2 cycles of prior exposure to a BCMA targeted agent is mandatory.

Exclusion Criteria:

* Primary systemic amyloid light chain amyloidosis, plasma cell leukemia, monoclonal gammopathy of undetermined significance, or smoldering myeloma.
* Uncontrolled infection within 14 days prior to first study intervention administration.
* Clinically significant cardiac (including valvular) or vascular disease within 3 months prior to first study intervention administration., eg, myocardial infarction, unstable angina, coronary (eg, coronary artery bypass graft, percutaneous coronary intervention) or peripheral artery revascularization, left ventricular ejection fraction \<40%, heart failure New York Heart Association Classes III and IV, stroke, transient ischemic attack, pulmonary embolism, other thromboembolic event, or cardiac arrhythmia (Grade 3 or higher by NCI CTCAE Version 5.0).
* Known acquired immunodeficiency syndrome-related illness or known human immunodeficiency virus (HIV) disease requiring antiviral treatment or active hepatitis A.
* Uncontrolled or active hepatitis B virus (HBV) infection.
* Active hepatitis C virus (HCV) infection.
* Any of the following within 3 months prior to first study intervention administration: treatment resistant peptic ulcer disease, erosive esophagitis or gastritis, infectious or inflammatory bowel disease.
* Second malignancy other than basal cell or squamous cell carcinoma of the skin or in situ carcinoma, unless they are successfully treated with curative intent for more than 3 years before first study intervention administration.
* Any anti-MM drug treatment within 14 days before first study intervention administration, including dexamethasone.
* Participants with a contraindication to treatment.
* Vaccination with a live vaccine 4 weeks before the start of the study.
* Seasonal flu and COVID-19 vaccines that do not contain live virus are permitted.
* Hemoglobin \<8 g/dL.
* Platelets \<50 × 10\^9/L.
* Absolute neutrophil count \<1.5 × 10\^9/L.
* Creatinine clearance \<30 mL/min/1.73m2.
* Total bilirubin \>1.5 × ULN, except for known Gilbert syndrome in which direct bilirubin should be ≤2.5 × ULN.
* Aspartate aminotransferase and/or alanine aminotransferase \>3 × ULN.
* Patients with grade 3 or 4 hypercalcemia.

Substudy 01:

-Malabsorption syndrome or any condition that can significantly impact the absorption of pomalidomide.

Substudy 02:

* History of resected/ablated basal or squamous cell carcinoma (SCC) of the skin or carcinoma in situ of the cervix, or other local tumors, even if considered cured by local treatment.
* Therapeutic doses of anticoagulants or antiplatelet agents within 7 days prior to the first dose of SAR439459.
* Prothrombin time or INR \>1.5 × upper limit of normal (ULN).

Substudy 03:

* Current corneal epithelial disease except mild punctate keratopathy
* Patients who have received prior therapy with belantamab mafodotin

Substudy 04:

* Central nervous system or leptomeningeal disease.
* Medical history of seizure.
* Participants currently receiving hepatically metabolized narrow therapeutic index drugs (eg, digoxin, warfarin) if cannot be closely monitored.

Substudy 05:

- Participant unable to swallow tablets

Substudy 06:

* History of active autoimmune disorders
* History of autoimmune hemolytic anemia or autoimmune thrombocytopenia
* Active graft versus host disease (GVHD) or ongoing immunosuppression for GVHD
* Prior allogenic hematopoietic stem cell transplant (allo-HSCT)
* Hemoglobin \< 9g/dL
* Prior therapy with any anti-CD47 or anti signal regulatory protein alpha agent

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.