Extended follow‐up of a phase 2 trial of bortezomib alone and in combination with dexamethasone for the frontline treatment of multiple myeloma

SummaryHigh-quality response to multiple myeloma (MM) therapy can be predictivefor improved outcomes. Novel agents may improve the depth of responsesand therefore prolong survival. We report on the extended follow-up of aphase II study in frontline MM of bortezomib alone and in combination withdexamethasone. Forty-nine previously untreated, symptomatic MM patientsreceived bortezomib 1AE3 mg/m 2 , days 1, 4, 8, 11, for up to six 3-week cycles.High-dose dexamethasone was added for patients not reaching either apartial response after cycle 2 or a complete response (CR) after cycle 4. Theoverall response rate in 48 evaluable patients was 90%, with 42% achieving atleast a very good partial response, of which 19% were CR/near CR. Thirty-sixpatients received high-dose dexamethasone with 28 (77%) showing improvedresponse. Twenty-seven patients have undergone successful stem-celltransplantation (SCT). After median follow-up of 49 months, 15 patientshave died; median overall survival has still not been reached, with anestimated survival at 4 years of 67%. Overall survival with and without SCTwas not different (P =0AE54). Grade 3/4 adverse events included neutropenia(10%), sensory neuropathy (6% grade 3), neuropathic pain (4% grade 3),and diarrhoea (4% grade 3). Bortezomib ± dexamethasone is an effective andwell-tolerated induction regimen for the frontline treatment of MM.Keywords: bortezomib, dexamethasone, frontline, multiple myeloma,induction therapy.