Photo by Linda Bartlett
The monoclonal antibody (mAb) elotuzumab may be a useful addition to the multiple myeloma (MM) arsenal, according to investigators involved in the phase 3 ELOQUENT-2 trial.
The trial showed that adding elotuzumab to treatment with lenalidomide and dexamethasone extended progression-free survival (PFS) in relapsed MM patients by about 5 months, on average, when compared to treatment with just lenalidomide and dexamethasone.
“It appears that, for patients with relapsed multiple myeloma who would otherwise be offered lenalidomide and dexamethasone, addition of this new targeted drug makes the outcomes even better,” said study investigator Sagar Lonial, MD, of Emory University in Atlanta, Georgia.
Dr Lonial presented data from ELOQUENT-2 at a presscast in advance of the 2015 ASCO Annual Meeting. Full data from the study will be presented at the meeting on June 2 as abstract 8508.
The study was funded by Bristol-Myers Squibb and AbbVie, the companies developing elotuzumab.
Dr Lonial explained that elotuzumab attaches to the cell surface protein SLAMF7, which is found on MM cells and natural killer (NK) cells. Scientists believe that elotuzumab mounts a 2-pronged attack on MM by targeting myeloma cells directly and by enhancing NK cells’ ability to kill myeloma cells.
In ELOQUENT-2, 646 patients with recurrent MM were randomized to receive elotuzumab plus lenalidomide and dexamethasone or only lenalidomide and dexamethasone (control).
The patients’ median age was 66. They had failed 1 to 3 prior treatments, and 35% of them were refractory to their last therapy. Thirty-two percent of patients had del(17p), and 9% had t[4;14].
At a median follow-up of 24 months, elotuzumab had reduced the risk of MM progression and death by 30%. Patients in the elotuzumab arm had significantly longer PFS than patients in the control arm—a median of 19.4 months and 14.9 months, respectively (P=0.0004).
The 1-year PFS was 68% in the elotuzumab arm and 57% in the control arm. The 2-year PFS was 41% and 27%, respectively. Dr Lonial pointed out that, unlike some other therapies, elotuzumab continued to improve PFS over time.
“[T]he idea of the maintenance of benefit over time really speaks to the power of an immune-based approach when we treat cancer,” he said.
“Patients who received elotuzumab had a longer duration of remission [and] a higher overall response rate, and this improvement in clinical parameters occurred without a significant increase in adverse events or toxicity. In fact, there was no reduction in quality of life for [patients in the] 3-drug arm.”
Mild infusion reactions occurred after the first few doses in 10% of patients who received elotuzumab. Most of these reactions were grade 1 or 2.
Common grade 3-4 adverse events (occurring in ≥ 15% of patients) in both the elotuzumab and control arms were neutropenia (25% and 33%, respectively) and anemia (15% and 16%, respectively).
In all, 210 patients died, 94 in the elotuzumab arm and 116 in the control arm.
“Based on this randomized, phase 3 trial, we hope that we will soon have a new treatment option for patients with relapsed or refractory myeloma . . . ,” Dr Lonial said.
The US Food and Drug Administration has already granted elotuzumab breakthrough therapy designation to treat MM patients who have received at least 1 prior therapy.
