Reeder CB, Reece DE, Kukreti V, Chen C, Trudel S, Hentz J, Noble B, Pirooz NA, Spong JE, Piza JG, Zepeda VH, Mikhael JR, Leis JF, Bergsagel PL, Fonseca R, and Stewart AK
We have studied a three-drug combination with cyclophosphamide, bortezomib and dexamethasone (CyBorD) on a 28-day cycle in the treatment of newly diagnosed multiple myeloma (MM) patients to assess response and toxicity. The primary endpoint of response was evaluated after four cycles. Thirty-three newly diagnosed, symptomatic patients with MM received bortezomib 1.3 mg/m(2) intravenously on days 1, 4, 8 and 11, cyclophosphamide 300 mg/m(2) orally on days 1, 8, 15 and 22 and dexamethasone 40 mg orally on days 1-4, 9-12 and 17-20 on a 28-day cycle for four cycles. Responses were rapid with a mean 80% decline in the sentinel monoclonal protein at the end of two cycles. The overall intent to treat response rate (>or= partial response) was 88%, with 61% of very good partial response or better (>or=VGPR) and 39% of complete/near complete response (CR/nCR). For the 28 patients who completed all four cycles of therapy, the CR/nCR rate was 46% and VGPR rate was 71%. All patients undergoing stem cell harvest had a successful collection. Twenty-three patients underwent stem cell transplantation (SCT) and are evaluable through day 100 with CR/nCR documented in 70% and >or=VGPR in 74%. In conclusion, CyBorD produces a rapid and profound response in patients with newly diagnosed MM with manageable toxicity.