A phase 2 study of modified lenalidomide, bortezomib and dexamethasone in transplant-ineligible multiple myeloma

We sought a regimen that incorporates optimal novel agents and balances efficacy with toxicity in transplant-ineligible multiple myeloma (MM) patients. Our study evaluated modified lenalidomide-bortezomib-dexamethasone (RVD lite) in this population and was administered over a 35-day cycle. Lenalidomide 15 mg was given orally on days 1-21; bortezomib 1·3 mg/m² weekly subcutaneously on days 1, 8, 15 and 22; and dexamethasone 20 mg orally was given on the day of and day after bortezomib for 9 cycles followed by 6 cycles of consolidation with lenalidomide and bortezomib. The primary objective was to evaluate the overall response rate (ORR); secondary objectives included safety, progression-free survival (PFS) and overall survival (OS). Fifty-three eligible patients were screened between April 2013 and May 2015; 50 received at least one dose of therapy. Median age at study entry was 73 years (range 65-91). The ORR was 86% and 66% of patients achieved a very good partial response or better. Median PFS was 35·1 months (95% confidence interval 30·9-not reached) and median OS was not reached at a median follow-up of 30 months. Peripheral neuropathy was reported in 31 (62%) patients with only 1 patient experiencing grade 3 symptoms. RVD lite is a well-tolerated and highly effective regimen, with robust PFS and OS, in the transplant-ineligible MM population.