This is a multi-phase study of JNJ-63723283 in combination with daratumumab compared with daratumumab alone in participants with multiple myeloma who have received at least 3 prior lines of therapy including a proteasome inhibitor (PI) and an immunomodulatory agent (IMiD) or whose disease is double refractory to both a PI and an IMiD. The study consists of Screening Phase (procedures performed within 28 days before enrollment), Open-Label Treatment Phase (with End-of-Treatment Visit to occur 4 weeks after the last dose of study treatment) and Follow-up phase (8 weeks after the last dose of study treatment). Ongoing safety evaluation during Part 1 and Part 2 will be overseen by the Safety Evaluation Team (SET). In Part 3, ongoing safety and efficacy evaluation will be performed by the Independent Data Monitoring Committee (IDMC).
The main purpose of this study is to assess the safety of the combination of JNJ-63723283 and daratumumab (Part 1); to compare the overall response rate (ORR) in participants treated with JNJ-63723283 in combination with daratumumab versus daratumumab alone (Part 2); and to compare progression-free survival (PFS) in participants treated with JNJ-63723283 in combination with daratumumab versus daratumumab alone (Part 3).