Effects of lenalidomide and dexamethasone treatment duration on survival in patients with relapsed or refractory multiple myeloma treated with lenalidomide and dexamethasone.
Author(s): San-Miguel JF, Dimopoulos MA, Stadtmauer EA, Rajkumar SV, Siegel D, Bravo ML, Olesnyckyj M, Knight RD, Zeldis JB, Harousseau JL, Weber DM
Affiliation(s): Servicio de Hematologia, Hospital Universitario de Salamanca, CIC, IBMCC, Spain. sanmigiz@usal.es
Publication date & source: 2011-02, Clin Lymphoma Myeloma Leuk., 11(1):38-43.
Publication type: Clinical Trial, Phase III; Randomized Controlled Trial
BACKGROUND: In two randomized phase III trials (MM-009 and MM-010), lenalidomide plus dexamethasone significantly prolonged time to progression and overall survival (OS) in patients with relapsed/refractory multiple myeloma compared with dexamethasone alone. In both trials the treatment was continued until disease progression or unacceptable toxicity. We conducted a subanalysis to determine if continuing therapy after achieving>/=partial response (PR) improved survival. PATIENTS AND METHODS: Data were collected on 212 patients who were treated with lenalidomide plus dexamethasone and achieved>/=PR. Kaplan-Meier survival estimates were compared between patients on continued treatment versus patients discontinuing therapy because of adverse events, withdrawal of consent, or other reasons. Time-dependent multivariate regression analyses were used to determine the benefit of continuing treatment with lenalidomide. RESULTS: A total of 174 patients received continued treatment until disease progression or death, and 38 patients discontinued therapy without progression. There was a trend toward longer median OS in patients who continued therapy (50.9 months vs. 35.0 months; P=.0594). When controlling for the number of previous antimyeloma therapies, beta2-microglobulin levels, and Durie-Salmon stage (which adversely affected survival in these patients), continued lenalidomide treatment (HR, 0.137; 95% CI, 0.045-0.417; P=.0005) or each additional cycle of lenalidomide (HR, 0.921; 95% CI, 0.886-0.957; P<.0001) were both associated with longer survival. CONCLUSION: Continued lenalidomide treatment until disease progression after achievement of >/=PR is associated with a significant survival advantage when controlling for patient characteristics. These findings should be confirmed in a prospectively designed trial.
|