Final outcomes of escalated melphalan 280 mg/m2 with amifostine cytoprotection followed autologous hematopoietic stem cell transplantation for multiple myeloma: high CR and VGPR rates do not translate into improved survival

Bone Marrow Transplant. 2019 Feb;54(2):293-299. doi: 10.1038/s41409-018-0261-y. Epub 2018 Jun 15.

Abstract

The most common preparative regimen for autologous transplantation (ASCT) in myeloma (MM) consists of melphalan 200 mg/m2 (MEL 200). Higher doses of melphalan 220-260 mg/m2, although relatively well tolerated, have not shown significant improvement in clinical outcomes. Several approaches have been pursued in the past to improve CR rates, including poly-chemotherapy preparative regimens, tandem ASCT, consolidation, and/or maintenance therapy. Since there is a steep dose-response effect for intravenous melphalan, we evaluated an alternative single ASCT strategy using higher-dose melphalan at 280 mg/m2 (MEL 280) with amifostine as a cytoprotectant as the maximum tolerated dose determined in an earlier phase I dose escalation trial. We report the final long-term outcomes of MM patients who underwent conditioning with MEL 280 with amifostine cytoprotection followed by ASCT. Although the complete response rate was quite high in the era pre-dating the routine use of novel therapies (proteasome inhibitors, immunomodulatory agents) (49%), the progression-free survival was a disappointing 22 months. The implications of this dichotomy between the excellent depth of ASCT response and progression-free survival are discussed.

Publication types

  • Clinical Trial, Phase II
  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Amifostine / administration & dosage*
  • Cytoprotection / drug effects
  • Disease-Free Survival
  • Dose-Response Relationship, Drug
  • Female
  • Hematopoietic Stem Cell Transplantation / methods*
  • Hematopoietic Stem Cell Transplantation / mortality
  • Humans
  • Male
  • Maximum Tolerated Dose
  • Melphalan / administration & dosage*
  • Middle Aged
  • Multiple Myeloma / mortality
  • Multiple Myeloma / therapy*
  • Prospective Studies
  • Remission Induction
  • Transplantation Conditioning / methods
  • Transplantation Conditioning / mortality
  • Transplantation, Autologous
  • Treatment Outcome

Substances

  • Amifostine
  • Melphalan