Extended survival in advanced and refractory multiple myeloma after single-agent thalidomide: identification of prognostic factors in a phase 2 studyof 169 patients

This report of a phase 2 trial of thalidomide (THAL) (200 mg/d; 200 mg incr ement every 2 weeks to 800 mg) far 169 patients with advanced myeloma (MM) (abnormal cytogenetics (CG), 67%; prior autotransplant, 76%) extends earlie r results in 84 patients. A 25% myeloma protein reduction was obtained in 3 7% of patients (50% reduction in 30% of patients; near-complete or complete remission in 14%) and was more frequent with low plasma cell labeling inde x (PCLI) (below 0.5%) and normal CG. Two-year event-free and overall surviv al rates were 20% +/- 6% and 48% +/- 6%, respectively, and these were super ior with normal CG, PCLI of less than 0.5%, and beta (2)-microglobulin of 3 mg/L. Response rates were higher and survival was longer especially in hig h-risk patients given more than 42 g THAL in 3 months (median cumulative do se) (landmark analysis); this supports a THAL dose-response effect in advan ced MM. (C) 2001 by The American Society of Hematology.