Allo-SCT for multiple myeloma in the era of novel agents: a retrospective study on behalf of Swiss Blood SCT.

Despite the introduction of novel drugs, cure of multiple myeloma remains rare. Allo-SCT can induce long-term remission, but randomized studies in advanced disease are lacking and the influence of novel drugs remains unclear. In our retrospective analysis of all patients with myeloma allografted in Switzerland, 95 patients were transplanted between 1988 and 2011. Most patients were heavily pre-treated, and 53% received novel drugs before transplant. In all, 51% were allografted after relapse or progression. Transplant trends changed over time with an increase in reduced intensity conditioning and unrelated donors. At the time of analysis 47 patients remained alive, with a median follow-up of survivors of 53 months. Acute GVHD II-IV and chronic GVHD (cGVHD) occurred in 49% and 53%, respectively; TRM at 5 years was 18%. Five-year OS and PFS were 51% and 29%, respectively. Patients who received transplant upfront vs after relapse had a significantly better outcome, as well as those who had a related donor and achieved CR post transplant. We found no impact of pre-treatment with novel drugs or cGVHD. Although long-term remission following allo-SCT can be achieved, GVHD and TRM remain major limitations. Our series suggests that benefit is highest when allo-SCT is used early in the disease.