ELOQUENT-2: A phase III, randomized, open-label trial of lenalidomide/dexamethasone (Len/Dex) with or without elotuzumab (Elo) in relapsed or refractory multiple myeloma (RR MM) (CA204-004).

TPS8112 Background: MM remains incurable and patients (pts) typically relapse or become refractory to current treatments. Novel regimens are needed to improve pt outcomes. Elo is a humanized monoclonal IgG1 antibody targeting the cell surface glycoprotein CS1, which is highly expressed on >95% of MM cells. Len/Dex is approved for treatment of relapsed MM and an objective response rate (ORR) of ~60% was reported in phase III trials of this combination in RR MM. In a phase II study (N=73) of Elo (10 or 20 mg/kg) in combination with Len/Dex in pts with RR MM, the 10 mg/kg group (n=36) demonstrated an ORR of 92% and median progression-free survival (PFS) that was not reached after a median follow-up of 14.1 months. Encouraging activity was seen in patients with high-risk cytogenetics and/or stage 2-3 disease. Based on these data, a randomized, open-label phase III trial has been initiated to determine if the addition of Elo to Len/Dex will improve PFS in patients with RR MM compared with Len/Dex alone. Methods: Pts (N=640) with RR MM and 1-3 prior therapies are eligible, including pts with mild or moderate renal impairment. Pts are randomized in a 1:1 ratio to receive 28-day cycles of Len 25 mg PO (days 1-21) and Dex 40 mg PO (days 1, 8, 15 and 22) with or without Elo. Elo dose and schedule is 10 mg/kg IV on days 1, 8, 15, 22 in the first 2 cycles and on days 1 and 15 in subsequent cycles. Dex 8 mg IV + 28 mg PO is used during the weeks with Elo. Treatment will continue until disease progression, death, or withdrawal of consent. Patients will be followed for tumor response every 4 weeks until progressive disease and then survival every 12 weeks. The primary endpoint is PFS (90% power for a hazard ratio [experimental to control arm] of 0.74) and the secondary endpoints are ORR and overall survival. Exploratory endpoints are safety, time to response, duration of response, time to subsequent therapy, health-related quality of life, and pharmacokinetics and immunogenicity of Elo. Potential biomarkers will also be assessed. As of January 10th, 2012, 107 pts were enrolled and 68 pts were treated. NCT01239797.