To compare the clinical efficacy of daratumumab injection combined with lenalidomide capsules and dexamethasone injection in the treatment of multiple myeloma (MM).

Patients with MM were divided into control group and treatment group according to the treatment method. Patients in the control group received the bortezomib for injection, lenalidomide capsules and dexamethasone injection (VRd) regimen; patients in the treatment group received the daratumumab injection, lenalidomide capsules and dexamethasone injection (DRd) regimen. The VRd regimen: Within each 28-day cycle, bortezomib for injection at 1.3 mg·m^-2, lenalidomide capsules at 25 mg·d^-1 and dexamethasone injection at 20 mg·d^-1 were administered according to the standard protocol. The DRd regimen: Based on lenalidomide capsules and dexamethasone injection , daratumumab injection at 16 mg·kg^-1 was added (once weekly in cycles 1-2, once every 2 weeks in cycles 3-6, and once every 4 weeks thereafter). Efficacy was evaluated after 3 cycles of treatment in both groups. Clinical efficacy, MM-related biomarkers and adverse reactions were compared between the two groups.

The study enrolled 88 patients, with 45 cases in the control group and 43 cases in the treatment group. Post-treatment evaluation revealed objective response rates (ORR) of 77.78% (35 cases/45 cases) and 90.70% (39 cases/43 cases) for the control and treatment groups, respectively, demonstrating no statistically significant intergroup difference (P>0.05). After treatment, the levels of hemoglobin of control group and treatment group were (102.85±15.87) and (109.71±16.24) g·L^-1, respectivley; the levels of β2-microglobulin (β2-MG) were (4.29±1.12) and (3.67±1.03) mg·L^-1, respectivley; the levels of lactate dehydrogenase (LDH) were (167.29±30.92) and (152.32±29.67) U·L^-1, respectivley; the levels of monoclonal protein (M protein) were (17.42±3.87) and (15.39±3.42) g·L^-1, respectivley; bone marrow plasma cells were (10.25±2.13)% and (8.92±2.06)%, respectivley; cluster of differentiation 3 positive (CD3⁺) were (62.45±8.74)% and (67.06±9.12)%, respectivley; CD4⁺ levels were (34.26±5.12)% and (37.68±5.33)%, respectivley; CD4⁺/CD8⁺ ratios were 1.16±0.24 and 1.28±0.22, respectivley. Compared the control group with treatment group, the differences of above indexes were all statistically significant (all P<0.05). The total incidence of peripheral neuropathy of control group and treatment group were 22.22% (10 cases/45 cases) and 2.33% (1 case/43 cases), respectivley; myelosuppression were 15.56% (7 cases/45 cases) and 37.21% (16 cases/43 cases), respectivley; infection were15.56% (7 cases/45 cases) and 34.88% (15 cases/43 cases), respectivley, all with statistically significant differences (P<0.05, P<0.01).

While ensuring clinical efficacy, the DRd regimen exerts more significant effects in improving immune function, levels of MM-related biomarkers, and quality of life, and significantly reduces the incidence of peripheral neuropathy. However, it is associated with increased risks of myelosuppression and infection.