The study evaluated the efficacy and safety of daratumumab, lenalidomide, and dexamethasone in patients with relapsed or refractory multiple myeloma who had previously received one or more lines of therapy. The primary endpoint was progression-free survival. The trial was designed as a randomized, open-label, multicenter phase 3 study with a 1:1 allocation ratio. Patients were treated until disease progression, unacceptable toxicity, withdrawal of consent, or death. The primary analysis was based on an interim analysis of 569 patients, with a median follow-up of 13.5 months. The results showed that the addition of daratumumab to lenalidomide and dexamethasone significantly prolonged progression-free survival, with a hazard ratio of 0.37 (95% CI, 0.27 to 0.52; P<0.001) compared to the control group. The overall response rate was higher in the daratumumab group (92.9% vs. 76.4%, P<0.001), and the rate of complete response or better was also significantly higher (43.1% vs. 19.2%, P<0.001). The most common adverse events were neutropenia, thrombocytopenia, and anemia, with a higher incidence of grade 3 or 4 events in the daratumumab group. Daratumumab-associated infusion-related reactions occurred in 47.7% of patients, mostly at grade 1 or 2. The study concluded that the addition of daratumumab to lenalidomide and dexamethasone significantly improved progression-free survival and overall response rates in patients with relapsed or refractory multiple myeloma, despite higher rates of neutropenia and infusion-related reactions.The study evaluated the efficacy and safety of daratumumab, lenalidomide, and dexamethasone in patients with relapsed or refractory multiple myeloma who had previously received one or more lines of therapy. The primary endpoint was progression-free survival. The trial was designed as a randomized, open-label, multicenter phase 3 study with a 1:1 allocation ratio. Patients were treated until disease progression, unacceptable toxicity, withdrawal of consent, or death. The primary analysis was based on an interim analysis of 569 patients, with a median follow-up of 13.5 months. The results showed that the addition of daratumumab to lenalidomide and dexamethasone significantly prolonged progression-free survival, with a hazard ratio of 0.37 (95% CI, 0.27 to 0.52; P<0.001) compared to the control group. The overall response rate was higher in the daratumumab group (92.9% vs. 76.4%, P<0.001), and the rate of complete response or better was also significantly higher (43.1% vs. 19.2%, P<0.001). The most common adverse events were neutropenia, thrombocytopenia, and anemia, with a higher incidence of grade 3 or 4 events in the daratumumab group. Daratumumab-associated infusion-related reactions occurred in 47.7% of patients, mostly at grade 1 or 2. The study concluded that the addition of daratumumab to lenalidomide and dexamethasone significantly improved progression-free survival and overall response rates in patients with relapsed or refractory multiple myeloma, despite higher rates of neutropenia and infusion-related reactions.