Outcomes of patients with NDMM, transplanted with Vel-Mel or Mel200 conditioning regimens

Conditioning regimens are regularly used to improve the efficacy of autologous hematopoietic stem cell transplantation (auto-HSCT) in patients with newly diagnosed multiple myeloma. However, currently, there is a lack of data surrounding the use of bortezomib (Vel) + melphalan 200 mg/m² (Mel200) (Vel-Mel) conditioning in the upfront clinical setting.

Recently, Beksac et al.¹ published a retrospective analysis in Bone Marrow Transplant investigating the outcomes of patients with newly diagnosed multiple myeloma, transplanted with Vel-Mel or Mel200. We summarize the key points below.

Study design¹

• This was a retrospective, registry-based study of the European Society for Blood and Marrow Transplantation (EBMT) database.
• Data was collected from patients who received their first auto-HSCT between January 1, 2010, and December 31, 2017, and were treated with Vel-Mel or Mel200.

Key findings¹

• A total of 4,388 patients were included in the study

• Vel-Mel = 292
• Mel200 = 4,096

• The median follow-up for all patients was 36.8 months

• The complete response/very good partial response was significantly higher in patients treated with Vel-Mel vs Mel200 at 100 days posttransplant (Figure 1)
• The 3-year cumulative incidence of complete response/very good partial response post-auto-HSCT was significantly higher in patients treated with Vel-Mel vs Mel200 (62% vs 48%, p < 0.001) but the median time to response was similar in both groups (Vel-Mel, 3.9 months and Mel200, 4.7 months).

CR, complete response; Mel200, melphalan 200 mg/m²; Vel-Mel, bortezomib + melphalan 200 mg/m²; VGPR, very good partial response.
*Adapted from Beksac, et al.¹

• The 3-year progression-free survival estimates were similar in both treatment groups (Vel-Mel, 46% and Mel200, 49%, p = 0.06).
• The 3-year overall survival was significantly better in patients treated with Mel200 at 85% vs 76% for patients treated with Vel-Mel (p < 0.001).
• The 3-year relapse incidence was also similar in both treatment groups (Vel-Mel, 55% and Mel200, 51%, p = 0.15).

Key learnings

Although patients achieved a greater depth of response with Vel-Mel vs Mel200 post-auto-HSCT, Vel-Mel was not associated with superior survival outcomes. However, differences in baseline population characteristics may have negated any possible effect of the more intensified conditioning on progression-free survival and overall survival. As a result, there is no current evidence to support the routine use of Vel-Mel conditioning in patients with newly diagnosed multiple myeloma, although larger prospective randomized studies are needed.