Response to Bortezomib Therapy for Multiple Myeloma (MM) in Actual Clinical Practice: Preliminary Effectiveness Findings of an International Observational Study.

Abstract

Background: Bortezomib (VELCADE®) is indicated for the treatment of MM in patients (pts) who have received at least 1 prior therapy. The electronic VELCADE Observational Study (eVOBS) is designed to evaluate the clinical and outcomes benefits of bortezomib in actual clinical practice. The study is open for enrollment between October 2006 and December 2008 in Belgium, France, Greece, Russia, Spain, Sweden, and Turkey with 3-year follow up. This report includes preliminary outcomes in pts with at least 4 months of data as of July 2007.Methods: Adults were eligible for study if they were scheduled to initiate bortezomib within the approved indication. All bortezomib dosages and concomitant treatments were permitted, except investigational therapies. Data on concomitant therapies, treatment response, and safety were collected prospectively during bortezomib therapy. Due to the non-interventional nature of the study, no predefined response criteria were mandated; response criteria could include M-protein, EBMT, SWOG, or others as defined by the investigator.Results: A total of 86 pts with at least 4 months of data were included in this analysis. Median age was 61 yrs, and 50 (58%) pts were male. Median interval since diagnosis was 3 yrs. The number of previous therapies for MM was 1, 2–3, and ≥4 for 38%, 44%, and 11% of pts, respectively. Demographic and clinical characteristics of the initial participants were similar to those of the participants in the prospective controlled phase 3 APEX trial (Richardson, N Engl J Med , 2005: 352; 2487–98). Most pts (61%) received bortezomib with dexamethasone. Adverse events (AEs) were reported in 61 (71%) pts, including Grade ≥3 AEs in 38% and Grade ≥4 AEs in 9%. AEs were treatment-related in 45% of patients and treatment-limiting in 9%. Presently, 72 of 86 pts have been evaluated for response, of whom 54 completed 4 or more cycles. Response rates are shown in the table. Updated data will be presented at the meeting.Best Response(n = 72)Complete response (CR)5 (7)Near complete response (nCR)9 (13)Partial response (PR)30 (42)Minimal response (MR)9 (13)Stable disease (SD)6 (8)Progressive disease (PD)13 (18)Overall response (≥PR)44 (61)Overall response (≥MR)53 (74)Conclusions: In this preliminary analysis of data from a prospective, observational study of actual clinical practice, most pts received bortezomib in combination with 1 or more other therapies for MM. Overall response in actual clinical practice was at least as common as previously reported with bortezomib monotherapy. Response rates and safety data from actual clinical practice demonstrate that bortezomib-containing regimens are effective and well-tolerated in the treatment of MM.