A Randomized Phase 3 Trial Of Melphalan-Lenalidomide-Prednisone (MPR) Or Cyclophosphamide-Prednisone-Lenalidomide (CPR) Vs Lenalidomide Plus Dexamethsone (Rd) In Elderly Newly Diagnosed Multiple Myeloma Patients
Authors: Palumbo Antonio , Magarotto Valeria , Bringhen Sara , Offidani Massimo , Pietrantuono Giuseppe , Liberati Anna Marina , Benevolo Giulia , Ledda Antonio , Gilestro Milena , Galli Monica , Patriarca Francesca , Genuardi Mariella , Giuliani Nicola , Zambello Renato , Zdenek Adam , La Fauci Alessia , Corradini Paolo , Falcone Antonietta Pia , Musolino Caterina , Rossi Davide , Caraffa Patrizia , Musto Pellegrino , Cavallo Federica , Hajek Roman , Boccadoro Mario 
Published: October 2019

Abstract

Background
Rd and MPR are effective treatments in newly diagnosed multiple myeloma (NDMM) patients (pts). In this study we compared a non-alkylating containing regimen (Rd) vs alkylating-based regimens (MPR/CPR) in elderly transplant ineligible NDMM pts.

Methods
Patients were randomized (2:1) to receive nine 28-day cycles of MPR/CPR or Rd. MPR: lenalidomide 10 mg/day for 21 days; melphalan orally 0.18 mg/Kg for 4 days in pts 65-75 years old and 0.13 mg/Kg in >75 years pts; prednisone 1.5 mg/Kg for 4 days; CPR: cyclophosphamide orally 50 mg/day for 21 days in pts 65-75 years old and 50 mg every other day (eod) in >75 years pts; lenalidomide 25 mg/day for 21 days; prednisone 25 mg every other day. Rd: lenalidomide 25 mg/day for 21 days; dexamethasone 40 mg on days 1,8,15 and 22 in pts 65-75 years old and 20 mg in those >75 years. After induction, patients were randomized to receive maintenance with lenalidomide alone (10 mg/day for 21 days) or with prednisone (25 mg eod on days 1-28), until disease progression. The primary endpoint was progression-free survival (PFS).

Results
Between October 2009 and October 2012, 659 pts were enrolled ( MPR/CPR:439 and Rd:220), and 641 pts were evaluable (MPR/CPR:430 and Rd:211). Patient characteristics were well balanced in the 2 groups: median age was 73 years in both groups, 38% of pts were older than 75 years, 27% had ISS stage III in both groups, 21% of patients both in the MPR/CPR and in the Rd groups had unfavorable FISH profile [t(4;14) or t (14;16) or del17p]. After induction, the response rates were similar in the 2 groups: at least PR rate was 75% versus 79% (p=0.52) and CR rate was 9% versus 7% (p=0.35), in the MPR/CPR and Rd group, respectively. No significant difference in response rate were reported between two alkylating containing regimens. After a median follow-up of 21 months, the 2-year PFS was 55% in MPR/CPR and 49% in Rd (HR=0.86, 95% CI: 0.66-1.12, p=0.26), and 2-year OS was 84% in MPR/CPR and 80% in Rd (HR= 0.93, 95% CI: 0.60-1.41, p=0.71)
At least one grade ≥3 hematological adverse event was reported in 51% with MPR/CPR and 29% with Rd (p<0.001), with a significant difference between the two alkylating agents (67% MPR and 31% CPR, p<0.001). At least one grade ≥3 extra-hematologic toxicities were similar in the two groups (31% with MPR/CPR and 28% with Rd, p=0.77). with no difference between two alkylating agents (31% both in MPR and CPR group). Second primary malignancies (SPM) were reported in 5 MPR patients (1 hematologic and 4 solid) in 1 CPR patient (hematologic) and in 2 Rd patients (both solid).

Conclusion
In a community-based population, triplet alkylating combinations did not lead to different PFS or OS clinical benefits over doublet therapy. Updated results will be presented at the meeting.

Disclosures:
Palumbo: Amgen: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Janssen Pharmaceuticals: Consultancy, Honoraria; Millenium: Consultancy, Honoraria; Onyx: Consultancy, Honoraria. Bringhen:Celgene: Honoraria. Giuliani:Celgene: Research Funding. Cavallo:Celgene: Honoraria; Celgene: Membership on an entity’s Board of Directors or advisory committees. Hajek:Celgene: Honoraria; Celgene: Consultancy. Boccadoro:Celgene: Consultancy, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees.