Daratumumab (DARA) + lenalidomide, bortezomib, and dexamethasone (RVd) in transplant-eligible newly diagnosed multiple myeloma (NDMM): A post hoc analysis of sustained minimal residual disease (MRD) negativity from GRIFFIN

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Background: In the primary analysis of the phase 2 randomized GRIFFIN study, DARA + RVd (D-RVd) improved the stringent complete response (sCR) rate by end of consolidation for transplant-eligible NDMM (42.4% vs 32.0%; 1-sided P = 0.068). With longer follow-up (median, 38.6 mo), D-RVd vs RVd improved MRD-negativity (10–5) rates in clinically relevant subgroups (ISS stage III, 71% vs 36%; high cytogenetic risk, 44% vs 29% [del17p, t(4;14), or t(14;16)]; revised high cytogenetic risk, 55% vs 32% [del17p, t(4;14), t(14;16), t(14;20), or gain 1q]). Here we present a post hoc analysis of sustained MRD negativity (median follow-up, 38.6 mo) in the same subgroups and in patients (pts) with ≥CR. Methods: Transplant-eligible NDMM pts were randomized 1:1 to 4 D-RVd/RVd induction cycles, ASCT, 2 D-RVd/RVd consolidation cycles, and 2 years of maintenance therapy with lenalidomide (R) ± DARA. For induction/consolidation (21-day cycles), pts received R (25 mg PO Days [D] 1-14), V (1.3 mg/m2 SC D1, 4, 8, 11), and d (40 mg PO weekly) ± DARA (16 mg/kg IV D1, 8, 15 of Cycles 1-4 and D1 of Cycles 5-6). In maintenance (28-day cycles), pts received R (10 mg PO D1-21; if tolerated, 15 mg in Cycles 10+) ± DARA (16 mg/kg IV Q8W/Q4W or 1800 mg SC per protocol amendments). The primary endpoint was sCR rate by end of consolidation. Results: The following features were balanced among randomized pts (D-RVd, n = 104; RVd, n = 103): high cytogenetic risk (16; 14), revised high cytogenetic risk (42; 37), gain 1q (34; 28), and ISS stage III (14; 14). Sustained MRD-negativity rates at 10–5 lasting ≥6 and ≥12 months were higher for D-RVd vs RVd among all high-risk subgroups (Table). D-RVd was superior to RVd for rates of sustained MRD negativity lasting ≥12 months for pts with ≥CR (53.7% vs 20.3%) and sCR (59.1% vs 17.4%; Table). Among all pts with sustained MRD negativity, only 1 D-RVd pt subsequently had disease progression, and 1 RVd pt died. Additional data on MRD at 10–6 and PFS will be presented. Conclusions: MRD data in GRIFFIN show that the addition of DARA to RVd induction/consolidation and R maintenance may lead to durable MRD-negativity (10–5) rates in pts with transplant-eligible NDMM with high cytogenetic risk, ISS stage III, and those who achieve ≥CR or sCR, however larger studies are needed. Clinical trial information: NCT02874742. [Table: see text]

A phase Ib study of TAK-079, an investigational anti-CD38 monoclonal antibody (mAb) in patients with relapsed/ refractory multiple myeloma (RRMM): Preliminary results

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Background: TAK-079 is a subcutaneously (SC) administered mAb with multiple modes of action for killing target cells. Here we report data from an ongoing dose finding study of TAK-079 monotherapy in patients with RRMM (NCT03439280). Methods: Pt were eligible after ≥ 3 lines of therapy and previous exposure to immunomodulatory drug (IMiD), proteasome inhibitor (PI), alkylating agent, and corticosteroid; prior anti-CD38 therapy allowed. Patients were refractory or intolerant to at least 1 PI and 1 IMiD. TAK-079 given as a SC injection weekly for 8 doses, every other week for 8 doses, then monthly until disease progression (PD) or unacceptable toxicity. SC injection was 2 mL administered in ≤ 1 minute. Results: 34 patients were enrolled across 5 fixed dose cohorts (TAK-079 45-135-300-600-1200 mg SC) as of 09 December 2019. Median age was 65 (50–81) years. At study entry, 65% were refractory to both an IMiD and PI; 82% refractory to last line of therapy, 21% of patients were previously exposed to at least 1 anti-CD38 monoclonal antibody. Median number of prior therapies was 4 (2,12). No ≥ Grade 1 early or late systemic infusion reactions (IRR) reported. Three ( < 1%) injection site reactions described in > 1200 injections administered; 2 mild pruritis and 1 moderate swelling. Drug related adverse events (AEs), any grade, occurring in at least 10% of patients were: fatigue (21%), anemia (18%), neutropenia (18%), leukopenia (15%). Neutropenia was the only drug related grade 3 AEs in 2 or more patients (n = 2); only drug related SAE was 1 Grade 3 diverticulitis. No drug-related grade 4 AEs, AEs leading to study discontinuation, or on-study deaths reported. Recommended phase 2 dose (RP2) is to be 600 mg based on no reported DLTs, no MTD identified, and preliminary efficacy (PFS and response [ORR]). At the RP2 dose, 9 patients received at least 6 cycles of therapy by the data cutoff; their ORR was 33%, median duration of response was not estimable. The clinical benefit rate (minimal response or better) in all 12 patients enrolled at the RP2 dose was 67%. At a median follow-up of 7.5 months, PFS not estimable at the RP2 dose. Conclusions: TAK-079 monotherapy is safe, generally well tolerated, and active in patients with RRMM through tested doses. Clinical activity occurred early and was durable. With no MTD identified, no IRRs, no significant hematologic toxicity, the RP2 dose is 600 mg. PFS, with a median FU of 7.5 months at the data-cut off, is not estimable at the RP2 dose. Updated safety and efficacy data will be presented. Clinical trial information: NCT03439280 .