Bortezomib, lenalidomide, and dexamethasone (VRD) is superior to lenalidomide, adriamycin, and dexamethasone (RAD) prior to risk-adapted transplant in newly diagnosed myeloma

8521

Background: High-dose chemotherapy (HDT) followed by autologous stem cell transplant (SCT) remains a standard of care in patients (pts) with newly diagnosed (ND) multiple myeloma (MM). While lenalidomide (R) maintenance is acknowledged to improve outcomes, intensified consolidation (such as tandem-SCT) has yielded conflicting results. Allogeneic (allo) SCT holds the promise of curative potential at the cost of higher treatment-related mortality (TRM). In a previous phase 2 study, we showed a very low TRM rate (6.1%) and feasibility of 12 months (mos) of R maintenance (maint), with auto/allo SCT after R/adriamycin/dexamethasone (RAD). This prompted us to compare, on a randomized rather than a “biological assignment” basis, a second auto- versus (vs) an allo-SCT in pts with an unfavorable prognosis. Methods: The current protocol (DSMM XIV, NCT01685814) was set up according to a double 2x2-factorial design. Post-induction (PInd) CR rate was the efficacy endpoint for the comparison of RAD vs bortezomib (V)/RD (VRD; 3 cycles each). If pts had achieved >VGPR to HDT, a second randomization (2ndR) compared immediate R maint (arm A2) with a second auto-SCT (B2). In case of < VGPR, pts were randomized between a second auto- (C2) and allo-SCT (D2). Planned R maint. duration was 36 mos, except after allo (12 mos). Results: Between 05/2012-06/2016, 476 pts were randomized and 469 received at least one dose of study drug. Pts’ median age was 55 (range, 32–65) years. 11.3% of pts had FISH del17p; 11.6% had t(4;14); and 4.4% had t(14;16). PInd CR rate was 11.8% (90% CI, 7.9%-16.3%) with RAD and 13.0% (90% CI, 8.9-18.0) with VRD (P = .697). 382 pts underwent R2 with 279 pts. (73%) in >VGPR and 103 (27%) in < VGPR, respectively. Median duration of R maint (N = 298) was 21.2 mos for A2, 23.1 mos for B2, 27.4 mos for C2, and 11.0 mos. for D2. At a median follow-up of 40.2 (0.5-87.0) months, median PFS from first randomization with RAD was 41.7 (95% CI, 35.4-48.5) mos vs. 53.7 (95% CI, 46.2-63.1) mos with VRD (P = .0439). Median PFS from 2ndR was 38.7 (95% CI, 30.3-47.3) mos for the 181 RAD vs. 50.7 (95% CI, 44.4-64.9) mos for the 201 VRD pts (P = .0126). Median overall survival (OS) cannot be estimated. With 47 deceased RAD vs 36 VRD pts, HR was .671 (95% CI, .435-1.037; P = .0703). Conclusions: In this study, median PFS benefit was 12 mos in favor of VRD vs. RAD despite comparable PInd CR. We show for the first time a len-PI to be superior to a len-chemo triplet, confirmed with positive OS trends. 3-year PFS for all consolidation arms will be presented. Clinical trial information: NCT01685814 .

Critical mercury concentration in tropical soils: Impact on plants and soil biological attributes

Mercury is a toxic element that becomes a problem when present at high concentrations in soils. Mercury toxicity in soils varies depending on chemical species, concentration, exposure routes, and organism vulnerability. There is little information regarding the toxicity of Hg in tropical soils, especially for establishing safe levels of this pollutant. The purpose of this study was to investigate Hg concentrations in two tropical soils and their effect on oats and common beans, as well as on soil biological attributes. The experiment was carried out in a greenhouse, following ISO 11.269-2 and OECD-208 guidelines. Oat and common bean were cultivated in a Typic Hapludox (TyHpx) and Rhodic Acrudox (RhAcx) contaminated with HgCl₂ at the following concentrations: 0, 2.5, 5.0, 10.0, 20.0, 40.0, and 80.0 mg of Hg kg^-1 of dry soil. The biological variables analyzed were seedling emergence, vegetative growth, chlorophyll content (SPAD index), gas exchange (photosynthetic rate, internal CO₂ concentration, transpiration rate, and stomatal conductance), and Hg concentration and accumulation in shoot dry matter. Microbial biomass carbon, soil basal respiration, and metabolic quotient (qCO₂) were also analyzed. Due to the sorptive characteristics of TyHpx, it had higher Hg concentrations than RhAcx. Mercury showed toxic effects on both oat and common bean species. However, common bean was affected only at concentrations higher than 20 mg kg^-1. The microbial community showed high sensitivity to soil Hg concentrations, but external factors, such as the plant species cultivated, influenced the sensitivity of the community. The microbiota was most sensitive in pots with common bean, and this effect was more pronounced at low clay and low organic matter contents (TyHpx). In this study, the concentration of 0.36 mg kg^-1 was critical for Hg in these soils, based on its deleterious effects on oat and common bean and on biological soil attributes.

MOR202 with low-dose dexamethasone (Dex) and in combination with pomalidomide/dex and lenalidomide/dex in relapsed or refractory multiple myeloma (RRMM): Interim analysis of a phase I/IIa dose-escalation study

8024

Background: CD38 is a type II transmembrane glycoprotein expressed by MM cells. MOR202, a human IgG1 CD38 monoclonal antibody, has shown high single-agent activity in preclinical models of MM and synergy in combination with immunomodulatory drugs (IMiDs), lenalidomide (LEN) and pomalidomide (POM). Methods: This interim analysis of a multicenter phase I/IIa study reports safety and efficacy data from RRMM patient (pt) cohorts treated with clinically relevant doses of MOR202 (2-hour IV infusion; 4, 8 and 16 mg/kg q1w) + Dex (≤40 mg), or at 8 or 16 mg/kg q1w with an IMiD/Dex. Primary objectives were to evaluate the safety, maximum tolerated dose (MTD) and recommended phase II dose of MOR202. Results: As of January 2017, 79 pts had been treated, including 44 in clinically relevant cohorts: 18 received MOR202 + Dex, 15 MOR202 + LEN/Dex and 11 MOR202 + POM/Dex. Pts had received a median of 3, 2 and 3 prior treatment lines, respectively. The MTD of MOR202 was not reached. Combinations were generally well tolerated, with grade ≥3 adverse events (AEs) mainly hematological; 2 pts discontinued due to a MOR202-related AE (one grade 4 thrombocytopenia; one grade 3 acute kidney failure). Infusion-related reactions (all grade 1 or 2) were seen in only 3/44 (7%) pts, and mainly occurred during the first infusion. In the MOR202 + Dex cohort, 5/17 (29%) evaluable pts (receiving at least 1 cycle of treatment) had a response, including 3 with partial responses (PRs) and 2 with very good PRs (VGPRs). Responses were also seen in 11/13 (85%, 8 PRs, 3 VGPRs) evaluable pts in the MOR202 + LEN/Dex cohort and 5/9 (56%, 2 complete responses, 3 PRs) in the MOR202 + POM/Dex cohort. Longest response duration was 17 months (MOR202/Dex). Preliminary analysis showed preservation of high CD38 levels on MM cells under MOR202 therapy. Conclusions: In heavily pretreated pts with RRMM, a 2-hour infusion of MOR202 administered at up to 16 mg/kg with Dex or in combination with an IMiD/Dex, showed a favorable safety profile, including excellent infusion tolerability. Promising preliminary efficacy and long-lasting tumor control was seen. Clinical trial information: NCT01421186.

Lenalidomide, doxorubicin hydrochloride and dexamethasone versus bortezomib, lenalidomide, and dexamethasone prior to scheduled stem cell transplant in newly diagnosed myeloma

8001

Background: In younger, medically fit patients (pts) with newly diagnosed (ND) multiple myeloma (MM), autologous stem cell transplant (SCT) remains a standard of care. Prior to SCT, induction triplets with at least one of the newer compounds are recommended. Bortezomib (V), lenalidomide (R) and dexamethasone (D; VRD) ranks amongst the most effective treatments. VRD + SCT proved superior over VRD alone in a randomized, controlled trial (RCT). We found encouraging efficacy and low toxicity with RAD (RD and adriamycin) + SCT and decided to compare RAD versus VRD induction in an RCT. Methods: The DSMM XIV study was set up according to a double 2x2-factorial design to enroll NDMM pts up to 65 years (yrs). Post-induction (PI) CR rate was the efficacy endpoint for the initial study phase. We hypothesized CR rate with RAD would be non-inferior to an estimated 20% CR with VRD. The study was powered to confirm non-inferiority of RAD at a 10% margin with a one-sided α level of .05. Minimal residual disease (MRD) was analyzed by eight-color flow cytometry (EuroFlow standards) on marrow samples. Results: 476 pts were randomized between 05/2012 and 06/2016, 469 of whom (median age 55 (range, 32–65) yrs) received at least one dose of study drug. 18.3% of pts had ISS stage III MM and 17.2%, elevated LDH. 11.3% of pts had del17p; 11.1% had t(4;14); and 4% had t(14;16). 232 pts were randomized to 3 four-week RAD cycles and 237 to 3 three-week VRD cycles, respectively. 89.7% of RAD versus 93.2% of VRD pts completed all induction cycles. PI CR rate was 11.8% (90% CI, 7.9%-16.3%) with RAD versus 13.0% (90% CI, 8.9-18.0) with VRD, (P = .697). 72/317 pts (22.7%) with paired baseline/PI samples achieved negative MRD at a median sensitivity level of 6.73x10-6. 47 (20.3%) RAD versus 35 (14.8%) VRD pts experienced treatment-emergent SAEs (P = .144). Treatment-related induction mortality was 0% in either arm. Conclusions: To the best of our knowledge, this is the first RCT to compare two lenalidomide-based triplets prior to SCT. The endpoint was met with comparable PI CR rates for RAD and VRD, respectively. Tolerability was encouraging in both arms. Follow-up data is needed to analyze time-dependent endpoints. Clinical trial information: NCT01685814.