Efficacy of Daratumumab, Lenalidomide, and Dexamethasone in Transplant-Ineligible Patients with Newly Diagnosed Multiple Myeloma and Impaired Renal Function from the Phase 3 Maia Study Based on Lenalidomide Starting Dose
Introduction: The phase 3 MAIA study (NCT02252172) evaluated the addition of daratumumab (D) to lenalidomide and dexamethasone (Rd) in patients (pts) with transplant-ineligible newly diagnosed multiple myeloma (NDMM). At a median follow-up of 56.2 months, D-Rd prolonged progression-free survival (PFS) and overall survival (OS) versus Rd alone, despite almost half of the pts in the Rd arm who received subsequent therapy receiving a daratumumab-containing regimen as any subsequent line of therapy (Facon T, et al. Presented at: European Hematology Association 2021 Virtual Congress. Abstract LB1901). Approximately 20% to 50% of pts with MM have baseline renal impairment that can affect the choice and efficacy of therapy (Dimopoulos MA, et al. Journal of Clinical Oncology. 2016;34[13]:1544-1557). Here, we report results from MAIA for D-Rd vs Rd in pts with impaired renal function based on lenalidomide starting dose at a median follow-up of 56.2 months. Methods: Pts with NDMM ineligible for high-dose chemotherapy and autologous stem-cell transplantation due to age ≥65 years or comorbidities were randomized 1:1 to receive D-Rd or Rd. Pts in both arms received 28-day cycles of oral Rd (R: 25 mg [10 mg recommended if creatinine clearance (CrCl) was 30-50 mL/min] on Days 1-21; d: 40 mg [20 mg if aged >75 years or body-mass index 2] on Days 1, 8, 15, 22). Pts in the D-Rd arm also received intravenous D (16 mg/kg once weekly for Cycles 1-2, once every 2 weeks for Cycles 3-6, and once every 4 weeks thereafter). Pts in both arms were treated until disease progression or unacceptable safety events. The primary endpoint was PFS, and a secondary endpoint was OS. Renal impairment was defined as a baseline CrCl of ≤60 mL/min. Results: 737 pts were randomized (D-Rd, n=368; Rd, n=369); 162 (44%) pts in the D-Rd arm and 142 (38%) pts in the Rd arm had renal impairment as defined. At a median follow-up of 56.2 months, in pts with renal impairment who received a lenalidomide starting dose of 25 mg (25 mg subgroup; D-Rd, n=60 [37%]; Rd, n=62 [44%]), a PFS and OS advantage was observed with D-Rd versus Rd (Table). In pts with renal impairment who received a lenalidomide starting dose of Table). Among pts in the 25 mg subgroup who died (D-Rd, n=12; Rd, n=29), disease progression was the primary cause of death in 6 (50%) pts in the D-Rd arm and 10 (34%) pts in the Rd arm. Among pts in the Conclusion: After ~5 years of follow-up, D-Rd showed a PFS improvement versus Rd in transplant-ineligible pts with NDMM and renal impairment regardless of lenalidomide starting dose. An OS advantage for D-Rd versus Rd was observed in pts with renal impairment who received a lenalidomide starting dose of 25 mg; in pts with renal impairment who received a lenalidomide starting dose of <25 mg, median OS was prolonged for D-Rd versus Rd, but the OS benefit was less pronounced. Overall, among pts with renal impairment, PFS and OS benefits of D-Rd versus Rd were observed regardless of lenalidomide starting dose; however, dose recommendations per the lenalidomide prescribing information should be followed. Many transplant-ineligible pts with NDMM may not receive a second line of therapy; our results support the frontline use of D-Rd to provide prolonged disease control in transplant-ineligible pts with NDMM and renal impairment.