DREAMM 8: This phase III trial will evaluate the safety and effectiveness of a type of immunotherapy, given in combination with chemotherapy (Arm A) or a type of targeted therapy (Arm B), in patients with multiple myeloma who have got worse or not responded to earlier treatmentA Phase III, Multicenter, Open-Label, Randomized Study to Evaluate the Efficacy and Safety of Belantamab Mafodotin in Combination With Pomalidomide and Dexamethasone (B-Pd) Versus Pomalidomide Plus Bortezomib and Dexamethasone (PVd) in Participants With Relapsed/Refractory Multiple Myeloma (DREAMM 8)

Exclusion

• Active plasma cell leukemia, symptomatic amyloidosis or active polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma proliferative disorder, and skin changes (POEMS) syndrome at the time of screening.
• Prior allogeneic SCT.
• Systemic anti-myeloma therapy (including chemotherapy and systemic steroids) within 14 days or five half-lives (whichever is shorter) preceding the first dose of study drug; prior treatment with a monoclonal antibody drug within 30 days of receiving the first dose of study drugs.
• Plasmapheresis within 7 days prior to the first dose of study drug.
• Received prior treatment with or intolerant to pomalidomide.
• Received prior Beta cell maturation antigen (BCMA) targeted therapy.
• Intolerant to bortezomib or refractory to bortezomib (for example; participant experienced progressive disease during treatment, or within 60 days of completing treatment, with a bortezomib-containing regimen of 1.3 mg/meter square [m^2] twice weekly).

• Evidence of cardiovascular risk including any of the following;

  1. Evidence of current clinically significant untreated arrhythmias, including clinically significant electrocardiogram abnormalities including second degree (Mobitz type II) or third degree atrioventricular (AV) block.
  2. Recent history within (3 months of screening) of myocardial infarction, acute coronary syndromes (including unstable angina), coronary angioplasty, or stenting or bypass grafting .
  3. Class III or IV heart failure as defined by the New York Heart Association (NYHA) functional classification system
  4. Uncontrolled hypertension.
• Any major surgery within the last 4 weeks.

• Previous or concurrent invasive malignancy other than multiple myeloma, except:

  1. The disease must be considered medically stable for at least 2 years; or
  2. The participant must not be receiving active therapy, other than hormonal therapy for this disease.
• Known immediate or delayed hypersensitivity reaction or idiosyncratic reaction to belantamab mafodotin or drugs chemically related to belantamab mafodotin, or any of the components of the study treatment.
• Evidence of active mucosal or internal bleeding.
• Cirrhosis or current unstable liver or biliary disease per investigator assessment defined by the presence of ascites, encephalopathy, coagulopathy, hypoalbuminemia, esophageal or gastric varices, persistent jaundice.
• Active infection requiring treatment.
• Known or active human immunodeficiency virus (HIV) infection, hepatitis B or hepatitis C will be excluded unless the protocol-defined criteria are met.
• Presence of active renal conditions (such as infection, severe renal impairment requiring dialysis or any other condition that could affect participant's safety).
• Ongoing Grade 2 peripheral neuropathy with pain within 14 days prior to randomization or ≥Grade 3 peripheral neuropathy.
• Active or history of venous and arterial thromboembolism within the past 3 months.
• Contraindications to or unwilling to undergo protocol-required anti-thrombotic prophylaxis.
• Current corneal disease except for mild punctate keratopathy.
• Any serious and/or unstable pre-existing medical, psychiatric disorder or other conditions (including laboratory abnormalities) that could interfere with participant's safety, obtaining informed consent or compliance to the study procedures.
• Pregnant or lactating female.