Combination therapy with lenalidomide plus dexamethasone (REV/DEX) for newly diagnosed myeloma

We report the results of a phase II trial using lenalidomide plus dexamethasone (Rev/Dex) as initial therapy for myeloma. 34 patients were enrolled. Lenalidomide was given orally 25 mg daily on days 1-21 of a 28-day cycle. Dexamethasone was given orally 40 mg daily on days 1-4, 9-12, 17-20 of each cycle. Objective response was defined as a decrease in serum monoclonal protein by 50% or greater and a decrease in urine M protein by at least 90% or to a level less than 200 mg/24 hours, confirmed by two consecutive determinations at least 4 weeks apart. Thirty-one of 34 patients achieved an objective response, including 2 (6%) achieving complete response (CR), and 11 (32%) meeting criteria for both very good partial response and near complete response, resulting in an overall objective response rate of 91%. Of the 3 remaining patients not achieving an objective response, two had minor response (MR) and one stable disease. Forty-seven percent of patients experienced grade 3 or higher non-hematologic toxicity, most commonly fatigue (15%), muscle weakness (6%), anxiety (6%), pneumonitis (6%) and rash (6%). Rev/Dex is a highly active regimen with manageable side-effects in the treatment of newly diagnosed myeloma.

S V Rajkumar^*, Suzanne R Hayman, Martha Q Lacy, Angela Dispenzieri, Susan M Geyer, Brian Kabat, Steven R Zeldenrust, Shaji Kumar, Philip R Greipp, Rafael Fonseca, John A Lust, Stephen J Russell, Robert A Kyle, Thomas E Witzig, and Morie A Gertz

Division of Hematology, Mayo Clinic, Rochester, MN, USA
Division of Biostatistics, Mayo Clinic, Rochester, MN, USA
Division of Hematology/Oncology, Mayo Clinic, Scottsdale, AZ, USA

Blood First Edition Paper, prepublished online August 23, 2005; DOI 10.1182/blood-2005-07-2817.