A Study Comparing Talquetamab Plus Pomalidomide, Talquetamab Plus Teclistamab, and Elotuzumab, Pomalidomide, and Dexamethasone or Pomalidomide, Bortezomib, and Dexamethasone in Participants With Relapsed or Refractory Myeloma Who Have Received an Anti-CD38 Antibody and Lenalidomide

PFS is defined as the duration from the date of randomization to either progressive disease or death, whichever comes first.

ORR is defined as the percentage of participants with best overall response of partial response (PR) or better according to international myeloma working group (IMWG) response criteria.

CR or better is defined as the percentage of participants with best overall response of CR or better according to IMWG response criteria.

VGPR or better is defined as the percentage of participants with best overall response of VGPR or better rate according to IMWG response criteria.

MRD-negative CR is defined as the percentage of participants who achieve both CR or better and MRD negativity at a threshold of 10^-5 at any timepoint after the date of randomization and before disease progression or start of subsequent antimyeloma therapy (SST).

OS is defined as the time from randomization to the date of participant's death.

PFS2 is defined as time from randomization to progression on the next line of therapy or death, whichever comes first.

TTNT is defined as the time from randomization to the start of SST.

Serum concentration of talquetamab and teclistamab will be reported.

Number of participants with ADAs to talquetamab and teclistamab will be reported.

Time to sustained worsening in symptoms, functioning and HRQoL is defined as the interval from the date of randomization to the start date of meaningful change. The MySIm-Q is a disease-specific patient-reported outcome (PRO) assessment complementary to the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 item (EORTC-QLQ-C30). It includes 17 items resulting in a symptom subscale and an impact subscale.

Time to sustained worsening in symptoms, functioning and HRQoL is defined as the interval from the date of randomization to the start date of meaningful change. EORTC-QLQ-C30 Version 3 includes 30 items that make up 5 functional scales (physical role, emotional, cognitive, and social), 1 global health status scale, 3 symptom scales (pain, fatigue, and nausea or vomiting), and 5 single symptom items (dyspnea, insomnia, appetite loss, constipation, and diarrhea) and a single impact item (financial difficulties). The recall period is 7 days ("past week"), and responses are reported using a verbal and numeric rating scales. The item and scale scores are transformed to a 0 to 100 scale. A high scale score represents a higher response level.

Time to sustained worsening in symptoms, functioning and HRQoL is defined as the interval from the date of randomization to the start date of meaningful change. The EQ-5D-5L is a 5-item questionnaire that assesses 5 domains including mobility, self-care, usual activities, pain or discomfort, and anxiety or depression plus a visual analog scale rating "health today" with anchors ranging from 0 (worst imaginable health state) to 100 (best imaginable health state).

Time to sustained worsening in symptoms, functioning and HRQoL is defined as the interval from the date of randomization to the start date of meaningful change. The PGI-S will be used as an anchor, external criterion, to determine meaningful change in scores for the MySIm-Q and EORTC-QLQ-C30 in this population. The response options are presented as a 5-point verbal rating scale from "none" to "very severe."

Time to sustained worsening in symptoms, functioning and HRQoL is defined as the interval from the date of randomization to the start date of meaningful change. The epstein taste survey consists of 17 items from the full 71 item PRO instrument, specific to taste changes developed for use in patients with head and neck cancer as a composite of the Vanderbilt Head and Neck Symptom Survey.

Change from baseline in symptoms, functioning, and HRQoL as assessed by MySIm-Q will be reported. The MySIm-Q is a disease-specific patient-reported outcome (PRO) assessment complementary to the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 item (EORTC-QLQ-C30). It includes 17 items resulting in a symptom subscale and an impact subscale.

Change from baseline in symptoms, functioning, and HRQoL as assessed by EORTC-QLQ-C30 will be reported. The EORTC-QLQ-C30 Version 3 includes 30 items that make up 5 functional scales (physical, role, emotional, cognitive, and social), 1 global health status scale, 3 symptom scales (pain, fatigue, and nausea or vomiting), and 5 single symptom items (dyspnea, insomnia, appetite loss, constipation, and diarrhea) and a single impact item (financial difficulties). The recall period is 7 days ("past week"), and responses are reported using a verbal and numeric rating scales. The item and scale scores are transformed to a 0 to 100 scale. A high scale score represents a higher response level. Thus, a high score for a functional scale represents a high or healthy level of functioning and a high score for the global health status represents high HRQoL, but a high score for a symptom scale or item represents a high level of symptomatology or problems.

Change from baseline in symptoms, functioning, and HRQoL as assessed by EQ-5D-5L will be reported. The EQ-5D-5L is a 5-item questionnaire that assesses 5 domains including mobility, self-care, usual activities, pain or discomfort, and anxiety or depression plus a visual analog scale rating "health today" with anchors ranging from 0 (worst imaginable health state) to 100 (best imaginable health state).

Change from baseline in symptoms, functioning, and HRQoL as assessed by PGI-S will be reported. The PGI-S will be used as an anchor, external criterion, to determine meaningful change in scores for the MySIm-Q and EORTC-QLQ-C30 in this population. The response options are presented as a 5-point verbal rating scale from "none" to "very severe."

Change from baseline in symptoms, functioning, and HRQoL as assessed by epstein taste survey will be reported. The epstein taste survey consists of 17 items from the full 71 item PRO instrument, specific to taste changes. developed for use in patients with head and neck cancer as a composite of the Vanderbilt Head and Neck Symptom Survey.

Percentage of participants with meaningful improvement in HRQol as assessed by EORTC-QLQ-C30 will be reported. The EORTC-QLQ-C30 Version 3 includes 30 items that make up 5 functional scales (physical, role, emotional, cognitive, and social), 1 global health status scale, 3 symptom scales (pain, fatigue, and nausea or vomiting), and 5 single symptom items (dyspnea, insomnia, appetite loss, constipation, and diarrhea) and a single impact item (financial difficulties). The recall period is 7 days ("past week"), and responses are reported using a verbal and numeric rating scales. The item and scale scores are transformed to a 0 to 100 scale. A high scale score represents a higher response level. Thus, a high score for a functional scale represents a high or healthy level of functioning and a high score for the global health status represents high HRQoL, but a high score for a symptom scale or item represents a high level of symptomatology or problems.

An AE is any untoward medical occurrence in a clinical study participant administered a pharmaceutical (investigational or non investigational) product. An AE does not necessarily have a causal relationship with the treatment. Severity of AEs will be graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) v5.0. by using standard grades as follows: Grade 1: Mild; asymptomatic or mild symptoms; Grade 2: Moderate; minimal, local or noninvasive intervention indicated; Grade 3: Severe but not immediately life threatening; hospitalization or prolongation of hospitalization indicated; Grade 4: Life-threatening consequences; and Grade 5: Death related to AE.