Addition of Isatuximab to Lenalidomide, Bortezomib and Dexamethasone As Induction Therapy for Newly-Diagnosed, Transplant-Eligible Multiple Myeloma Patients: The Phase III GMMG-HD7 Trial

Abstract Background: In newly-diagnosed multiple myeloma (NDMM), lenalidomide/bortezomib/dexamethasone (RVd) is one of the most widely used combination regimens. Anti-CD38 monoclonal antibodies (CD38-moAb) increase efficacy when added to standard-of-care regimens. Here we present the first primary endpoint of the randomized, open-label, multicenter, phase III GMMG-HD7 trial, comparing RVd without (arm IA) or with the CD38-moAb isatuximab (Isa, arm IB) with regard to the rate of minimal residual disease (MRD) negativity after induction therapy in patients with transplant-eligible NDMM. Patients and Methods: Patients with transplant-eligible NDMM at 67 sites in Germany were equally randomized to receive three 42-day cycles of RVd (lenalidomide 25 mg/d p.o., d1-14 and d22-35; bortezomib 1.3 mg/m 2 s.c. d1, 4, 8, 11, 22, 25, 29, 32; dexamethasone 20 mg/d d1-2, 4-5, 8-9, 11-12, 15, 22-23, 25-26, 29-30, 32-33) in both arms. Isa was added to arm IB only (10 mg/kg i.v., cycle 1: d 1, 8, 15, 22, 29; cycles 2-3: d 1, 15, 29). Randomization for induction was stratified according to revised International Staging System (R-ISS). Primary endpoint of the trial was MRD negativity assessed by next-generation flow (NGF, cut off 1x10 -5) after induction. Secondary endpoints included rates of complete response (CR) after induction and safety. Data cut-off for the present analysis was April 2021. Results: Between 10/2018 and 09/2020, 662 patients were included in the trial. 660 patients were eligible for intention-to-treat analysis and 658 patients started induction (RVd: 329/328 and Isa-RVd: 331/330). Median age was 58 (range 26-70) years and baseline characteristics were well balanced between treatment arms. On induction, 35 (10.6%) and 18 (5.4%) patients discontinued treatment in the RVd vs. Isa-RVd arms (p=0.02). Among these, 8 (2.4%, RVd) vs. 7 (2.1%, Isa-RVd) patients discontinued induction due to adverse events (AE). 293 (89.1%) vs. 312 (94.3%) patients in the RVd vs. Isa-RVd arms continued further study treatment after induction. MRD negativity rates after induction were 35.6% vs. 50.1% (odds ratio [OR]=1.83, 95% confidence interval [95% CI]: 1.34-2.51, p<0.001) for RVd vs. Isa-RVd, respectively. On multivariate analyses including treatment arm, R-ISS, performance status, renal impairment, age and sex, treatment with Isa-RVd (vs. RVd) remained the only significant predictor for increased MRD negativity after induction (OR=1.82, 95% CI: 1.33-2.49, p<0.001). While the rates of CR after induction did not yet differ between the RVd vs. Isa-RVd arms (21.6% vs. 24.2%, p=0.46), the rate of very good partial response or better (≥VGPR) was significantly higher in the Isa-RVd arm (60.5% vs. 77.3%, p<0.001). The rates of progressive disease were 4.0% (RVd) vs. 1.5% (Isa-RVd). At least one AE (grade ≥3) on induction occurred in 61.3% (RVd) and 63.6% (Isa-RVd) of patients (p=0.57). Most common AE (grade ≥3) by system organ class (SOC) for RVd vs. Isa-RVd were: "investigations": 23.5% vs. 23.9% (p=0.93), "blood and lymphatic system disorders": 16.8% vs. 25.8% (p=0.006), "infections and infestations": 10.4% vs. 13.0% (p=0.33) and "nervous system disorders": 10.1% vs. 8.5% (p=0.50). Rates of serious AE (SAE, any grade) on induction were similar between RVd and Isa-RVd (36.3% vs. 34.8%, p=0.75). Eight (RVd) and four (Isa-RVd) patients died during induction. Conclusions: The GMMG-HD7 trial met its primary endpoint. To the best of our knowledge this is the first phase III trial to demonstrate superiority of MRD negativity rates after induction by adding a CD38-moAb to RVd. There were no increased rates of SAE or early discontinuation in patients treated with Isa-RVd compared to RVd. The trial is ongoing, including analyses post autologous transplantation, which is followed by a second randomization to compare the efficacy of the addition of Isa to lenalidomide maintenance. Disclosures Goldschmidt: Takeda: Consultancy, Research Funding; Sanofi: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Adaptive Biotechnology: Consultancy; Incyte: Research Funding; GSK: Honoraria; Chugai: Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Celgene: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; BMS: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Janssen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Johns Hopkins University: Other: Grant; Molecular Partners: Research Funding; MSD: Research Funding; Mundipharma: Research Funding; Dietmar-Hopp-Foundation: Other: Grant; Novartis: Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding. Mai: Celgene / BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding; Glaxo Smith Kline: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel accommodations and expenses, Research Funding. Fenk: Takeda: Honoraria; GSK: Honoraria; Amgen: Honoraria; Janssen: Honoraria; BMS/Celgene: Honoraria. Besemer: Takeda: Honoraria; Janssen: Honoraria; GSK: Honoraria. Dürig: Janssen: Membership on an entity's Board of Directors or advisory committees, Other: Travel Support, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Other: Travel Support, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees. Schroers: BMS/Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; GSK: Consultancy, Honoraria; Takeda: Honoraria. Metzler: Takeda: Consultancy; BMS: Consultancy; GSK: Consultancy; Amgen: Consultancy; Janssen: Consultancy; AstraZeneca: Consultancy; Pfizer: Consultancy; Sanofi: Consultancy. Haenel: Takeda: Consultancy, Honoraria; Jazz: Consultancy, Honoraria; GSK: Consultancy; Bayer Vital: Honoraria; Roche: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Amgen: Consultancy; Celgene: Consultancy, Honoraria. Mann: Cellgene: Consultancy. Asemissen: GSK: Honoraria; Pfizer: Honoraria; Celgene BMS: Honoraria. Heilmeier: Sanofi-Aventis Dtld. GmbH: Consultancy. Kriegsmann: Sanofi: Honoraria. Weinhold: Sanofi: Honoraria. Holderried: Amgen: Speakers Bureau; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees; Eurocept Pharmaceuticals: Other: Travel support; MSD: Speakers Bureau; Gilead Sciences: Consultancy, Membership on an entity's Board of Directors or advisory committees; Abbvie: Other: Travel support; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Other: Travel support; Therakos: Other: Travel support; Daiichi Sankyo: Other: travel support; Medac: Other: Travel support; Jazz Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees. Trautmann-Grill: Sanofi: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; GSK: Consultancy, Honoraria. Gezer: Amgen: Consultancy, Other: Invited Speaker; Takeda: Consultancy, Other: Invited Speaker; BMS: Consultancy, Other: Invited Speaker; Celgene: Consultancy, Other: Invited Speaker. Khandanpour: GSK: Honoraria; Takeda: Honoraria; Janssen: Honoraria; AstraZeneca: Honoraria, Research Funding; Pfizer: Honoraria; Sanofi: Honoraria, Research Funding; BMS/Celgene: Honoraria. Knauf: Amgen: Honoraria; Abbvie: Honoraria; Beigene: Consultancy, Honoraria; BMS: Honoraria; Celgene: Honoraria; Janssen: Consultancy, Honoraria; Sanofi: Honoraria; AstraZeneca: Consultancy, Honoraria. Munder: GSK: Consultancy; Amgen: Honoraria; Sanofi: Consultancy; Takeda: Consultancy, Honoraria; Abbvie: Consultancy; BMS: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Incyte: Research Funding. Hoffmann: Sanofi-Aventis: Consultancy. Raab: Roche: Consultancy; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy, Honoraria; Janssen: Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees. Salwender: GlaxoSmithKline: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Sanofi: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES; Chugai: Honoraria; Oncopeptides: Honoraria; Takeda: Honoraria; Amgen: Honoraria, Other: TRAVEL, ACCOMMODATIONS,