SAN DIEGO – Patients with newly diagnosed multiple myeloma who were ineligible for transplant had a 44% reduction in the risk of disease progression or death when they were treated with the anti-CD38 monoclonal antibody daratumumab (Darzalex) added to lenalidomide (Revlimid) and dexamethasone, compared with lenalidomide-dexamethasone alone, an interim analysis from the MAIA trial showed.
Among 737 patients in a phase 3 trial, median progression-free survival – the primary endpoint – had not been reached after a median follow-up of 28 months for patients randomized to daratumumab, lenalidomide, and dexamethasone (DRd), versus 31.9 months for patients randomized to lenalidomide and dexamethasone (Rd).
The 30-month PFS rate in the DRd arm was 71%, compared with 56% for the Rd arm. This difference translated into a hazard ratio (HR) for progression of 0.56 (P less than .0001), reported Thierry Facon, MD, of Hôpital Claude Huriez and the University of Lille, France.
“These results support DRd as a new standard of care for elderly patients with myeloma who are ineligible for transplant,” he said at the annual meeting of the American Society of Hematology.
Dr. Facon and his colleagues had previously shown in the FIRST trial that in newly diagnosed transplant-ineligible patients, continuous treatment with lenalidomide and low-dose dexamethasone was associated with significant overall survival and PFS benefits, compared with melphalan-prednisone-thalidomide.
In the POLLUX trial, investigators reported that in patients with multiple myeloma that was refractory or had relapsed after at least one prior line of therapy, the DRd combination was associated with a 63% reduction in the risk for disease progression or death, compared with Rd alone.
Theis a pivotal, phase 3 study pitting DRd against Rd in transplant-ineligible patients with newly diagnosed multiple myeloma.
Patients with untreated disease who had Eastern Cooperative Oncology Group (ECOG) status of 0-2 and creatinine clearance rates of at least 30 mL/min were enrolled. Patients were randomly assigned to either DRd, with intravenous daratumumab 16 mg/kg weekly for cycles 1 and 2, every other week for cycles 3 through 6, and every 4 weeks from cycle 7 until disease progression, plus lenalidomide 25 mg orally per day on days 1-21 until disease progression, and dexamethasone 40 mg orally or intravenously weekly until disease progression; or to the same regimen without daratumumab.
The median patient age was 73 years and 99% of all patients were aged 65 years or older. Demographic and clinical characteristics were well balanced between the treatment arms.
The primary endpoint of progression-free survival was superior with DRd.
DRd also was associated with a significantly higher overall response rate (93% vs. 81%), complete response rate (48% vs. 25%), very good partial response or better rate (79% vs. 53%), and minimal residual disease (MRD) negativity rate (24% vs. 7%; P less than .0001 for all comparisons).
The DRd combination was associated with infusion-related reactions in 41% of patients, but only 3% were grade 3 or 4 in severity.
Hematologic treatment-emergent adverse events (TEAE) grade 3 or greater that were more common with DRd included neutropenia (50% vs. 35%) and lymphopenia (15% vs. 11%). Conversely, thrombocytopenia (7% vs. 9%, grade 3 or 4) and anemia (12% vs. 20%) were more frequent with Rd.
Nonhematologic TEAEs that were more frequent with DRd included diarrhea, constipation, fatigue, peripheral edema, and pneumonia. Rates of asthenia, back pain, nausea, and deep vein thrombosis/pulmonary embolism were similar between the study arms.
Janssen funded the study. Dr. Facon reported speakers bureau and advisory board participation for Celgene, Janssen, and Takeda; and advisory board participation for Sanofi, Amgen, Karyopharm, and Oncopeptides.
SOURCE: Facon T et al. ASH 2018, Abstract LBA-2.