ASH 2017 | Elotuzumab Maintenance After ASCT  

The MM Hub is excited to share research findings from the 59th American Society of Hematology (ASH) Annual Meeting in Atlanta, Georgia.  On Monday 11 December, the evening oral abstract session took place for Myeloma entitled: Therapy, excluding Transplantation Studies in Relapsed and Refractory Multiple Myeloma.  Dr. Sheeba Thomas of M.D. Anderson Cancer Center in Houston, Texas discussed Abstract #840: Preliminary Results of a Phase II Study of Lenalidomide-Elotuzumab as Maintenance Therapy Post-Autologous Stem Cell Transplant in Patients with Multiple Myeloma. The MM summary here is based both on updated data presented at the ASH session and therefore may supersede the data in the pre-published abstract.

Elotuzumab is a humanized anti-SLAMF7 antibody, which has dual anti-myeloma activity by binding directly to SLAMF7 on NK cells and indirectly by binding of the Fc portion to the activating Fc receptor, CD16. Lenalidomide has been shown to improve progression-free survival (PFS) as maintenance therapy after ASCT and in Relapsed and Refractory Multiple Myeloma (RRMM). The aim of this study was to assess the safety and efficacy of adding elotuzumab to lenalidomide maintenance following ASCT.  Eligibility included receipt of ≤2 lines of therapy before ASCT, ASCT ≤ 18 months of starting induction therapy for Newly Diagnosed MM, and able to start therapy within 60­-210 days of ASCT.

Key Findings:

• Patients (pts) (n = 68) 
• Median age = 68 years
• Median time from ASCT to start of lenalidomide-elotuzumab = 158 days
• High Risk Disease
  • high risk cytogenetic features = 46%
  • high risk by IMWG criteria = 31%
  • Improvement in quality of response from study entry = 36%
  • Median cycles to best response = 3.5
• Best response: ≥VGPR = 91%; ≥CR = 51%
• Two-year estimated PFS = 88%
  • Median follow-up = 23 months
  • Median PFS = not reached
• Depth of response: 20% CR/sCR:13 pts in CR hve been tested for MRD: 10 were mRD negative at study entry; 3 have converted from CGPR to MRD negative
• No significant difference in PFS stratified by cytogenetic risk
• Median overall survival (OS) not reached
• Adverse Events (AEs)
  • Hematologic AEs: anemia = 71%, neutropenia = 69%, thrombocytopenia = 68%, febrile neutropenia = 9%
  • Grade 3 Hematologic AEs: anemia = 6%, neutropenia = 31%, thrombocytopenia = 7%, febrile neutropenia = 4%
  • Other AEs: Fatigue = 76%, myalgia = 71%, diarrhea = 69%, respiratory infections = 57%, nausea/vomiting = 57%, dizziness = 56%, memory impairment = 46%, dyspnea = 44%, constipation = 44%, limb edema = 38%, other infections = 38%, peripheral neuropathy = 37%, rash = 29%, mucositis = 28%
• Secondary primary malignancies (SPMs) = 4 pts

The combination of elotuzumab and lenalidomide maintenance therapy was well tolerated and provided good efficacy for VGPR or better response rates.  Improved quality of response while on therapy was achieved in 36% of patients. Further study is need to determine the impact of this maintenance combination on PFS and OS following ASCT.