An analysis of clinical trials assessing the efficacy and safety of single-agent thalidomide in patients with relapsed or refractory multiple myeloma

Abstract

Given that the efficacy/safety of thalidomide for relapsed or refractory multiple myeloma have not been well characterized in a randomized, controlled setting, an analysis of larger, single-agent trials was conducted. Nine trials met the following inclusion criteria: primary population of multiple myeloma; all patients relapsed or refractory; single-agent thalidomide; and sample size ≥50. At median doses of 200 – 800 mg per day, the pooled overall response rate (ORR) was 28.2% (95% CI: 22.6 – 33.7%), including a complete response (CR) rate of 1.6% (95% CI: 0.3 – 2.9%) and partial response rate of 26.0% (95% CI: 20.1 – 32.0%). Response was typically based on M-protein reduction alone. Peripheral neuropathy (PN) incidence varied from 12 – 44%, possibly impacted by the short median follow-up (9 – 29 months). Pooled venous thromboembolism (VTE) incidence was 2.7% (95% CI: 1.1 – 4.3%) and discontinuation due to intolerance (DDI) rate was 14.9% (95% CI: 12.0 – 17.7%). Overall survival (OS), progression-free survival (PFS) and PN incidence were not pooled due to lack of reporting and trial heterogeneity. Prognostic factors identified included B₂M (PFS) and advanced age (PFS and OS). Overall, thalidomide demonstrated an ORR approaching 30%, with low CR rate of 1.6% and VTE and DDI incidences of 3% and 15%, respectively.

Keywords:

• Thalidomide
• refractory
• relapsed
• myeloma