A Study of Teclistamab in Combination With Daratumumab and Lenalidomide (Tec-DR) and Talquetamab in Combination With Daratumumab and Lenalidomide (Tal-DR) in Participants With Newly Diagnosed Multiple Myeloma

Prior treatment

• Received any prior therapy for multiple myeloma or smoldering myeloma other than a short course of corticosteroids (not to exceed total of 160 milligrams \[mg\] dexamethasone or equivalent). In addition, received a cumulative dose of systemic corticosteroids equivalent to greater than or equals to (\>=) 20 mg of dexamethasone within 14 days before randomization
• Had a stroke, transient ischemic attack, or seizure within 6 months prior to randomization

Other illness

• Known allergies, hypersensitivity, or intolerance to teclistamab or talquetamab excipients

Age

• Myeloma Frailty Index of \>=2 with the exception of participants who have a score of 2 based on age alone

Other

• Had plasmapheresis within 28 days of randomization
• Known contraindications to the use of daratumumab or lenalidomide per local prescribing information

• Have a diagnosis of multiple myeloma according to the International Myeloma Working Group (IMWG) diagnostic criteria
• Be newly diagnosed and not considered a candidate for high-dose chemotherapy with autologous stem cell transplant (ASCT) due to: ineligible due to advanced age OR; ineligible due to the presence of comorbid condition(s) likely to have a negative impact on tolerability of high-dose chemotherapy with ASCT OR; deferral of high-dose chemotherapy with ASCT as initial treatment
• Have an Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 2
• A participant must agree not to be pregnant, breastfeeding, or planning to become pregnant while enrolled in this study or within 6 months after the last dose of study treatment
• A participant must agree not to plan to father a child while enrolled in this study or within 100 days after the last dose of study treatment