Safety and efficacy of a dexamethasone-sparing regimen with daratumumab and lenalidomide in patients with frailty and newly diagnosed multiple myeloma (IFM2017-03): a phase 3, open-label, multicentre, randomised, controlled trial

BACKGROUND: Patients with frailty and newly diagnosed multiple myeloma have worse outcomes due to higher rates of adverse events (AEs) and treatment discontinuation. This study evaluated a dexamethasone-sparing regimen of daratumumab plus lenalidomide versus lenalidomide plus dexamethasone in frail patients with newly diagnosed multiple myeloma. METHODS: In this prospective, randomised, open-label trial, conducted at 61 active Intergroup Francophone of Myeloma centres, patients aged 65 years or older with newly diagnosed multiple myeloma and an Eastern Cooperative Oncology Group proxy frailty score of 2 or more were randomly assigned 2:1 to receive daratumumab (1800 mg subcutaneously) plus oral lenalidomide (25 mg daily for 21 days of a 28 day cycle) and dexamethasone (20mg weekly) for two cycles (dexamethasone-sparing group) or lenalidomide (25 mg daily) and oral dexamethasone (20 mg weekly; control group), with stratification by International Staging System, age, and centre. The primary endpoint was progression-free survival. Efficacy was assessed in the intention-to-treat population and safety was assessed in all patients exposed to at least one dose of randomised intervention. This trial is registered with ClinicalTrials.gov, NCT03993912, and is complete. FINDINGS: From Oct 18, 2019 to July 20, 2021, 335 patients were screened, of whom 295 patients were randomly assigned (200 to lenalidomide plus daratumumab, 95 to lenalidomide plus dexamethasone). The median age was 81 years (IQR 77-84), with 180 (61%) aged older than 80 years, and 151 (51%) patients were female and 144 (49%) were male. Median follow-up was 46·3 months (IQR 46·0-52·7). Median progression-free survival was 53·4 months (95% CI 35·3-not reached) in the dexamethasone-sparing group versus 22·5 months (16·5-39·0) in the control group (hazard ratio [HR] 0·51, 95% CI 0·37-0·70, p<0·0001). The most common grade 3-5 AEs were neutropenia (110 [55%] of 200 patients in the dexamethasone-sparing group vs 23 [24%] of 95 patients in the control group), and infection (38 [19%] vs 20 [21%]). Serious adverse events occurred in 126 patients (63%) in the dexamethasone-sparing group and 66 patients (69%) in the control group. AEs leading to death occurred in 23 patients (12%) in the dexamethasone-sparing group and 12 patients (13%) in the control group, with 4 (2%) and 2 (2%) grade 5 treatment-emergent adverse events, respectively. INTERPRETATION: In the IFM2017-03 trial, use of lenalidomide plus daratumumab, with dexamethasone limited to the first 2 treatment cycles, reduced the risk of progression or death compared with lenalidomide plus dexamethasone, with no additional safety concerns. Lenalidomide plus daratumumab could therefore be considered as a treatment option for older patients with frailty and newly diagnosed multiple myeloma. FUNDING: The study was funded by Johnson & Johnson.