Prognostic value of minimal residual disease negativity in myeloma: combined analysis of POLLUX, CASTOR, ALCYONE, and MAIA.

We explored minimal residual disease (MRD) in relapsed/refractory multiple myeloma (RRMM) and transplant-ineligible (TIE) newly diagnosed multiple myeloma (NDMM) using data from 4 phase 3 studies (POLLUX, CASTOR, ALCYONE, and MAIA). Each study previously demonstrated that daratumumab-based therapies improved MRD negativity rates and reduced the risk of disease progression or death by approximately half vs standards of care. We conducted a large-scale pooled analysis for associations between patients achieving complete response or better (≥CR) with MRD-negative status and progression-free survival (PFS). MRD was assessed via next-generation sequencing (10-5 sensitivity threshold). Patient-level data were pooled from all 4 studies and for patients with TIE NDMM and patients with RRMM who received ≤2 prior lines of therapy (≤2 PL). PFS was evaluated by response and MRD status. Median follow-up (months) was 54.8 for POLLUX, 50.2 for CASTOR, 40.1 for ALCYONE, and 36.4 for MAIA. Patients who achieved ≥CR and MRD negativity had improved PFS vs those who failed to reach CR or were MRD positive (TIE NDMM and RRMM hazard ratio [HR] 0.20, P < .0001; TIE NDMM and RRMM ≤2 PL HR 0.20, P < .0001). This benefit occurred irrespective of therapy or disease setting. A time-varying Cox proportional hazard model confirmed that ≥CR with MRD negativity was associated with improved PFS. Daratumumab-based treatment was associated with more patients reaching ≥CR and MRD negativity. These findings represent the first large-scale analysis with robust methodology to support ≥CR with MRD negativity as a prognostic factor for PFS in RRMM and TIE NDMM. These trials were registered at www.clinicaltrials.gov as #NCT02076009, #NCT02136134, #NCT02195479, and #NCT02252172.

Plain language summary of the MAIA study of daratumumab plus lenalidomide and dexamethasone for the treatment of people with newly diagnosed multiple myeloma.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of a clinical trial called MAIA. The trial tested 2 combinations of cancer drugs (daratumumab plus lenalidomide and dexamethasone compared with lenalidomide and dexamethasone) in people with newly diagnosed multiple myeloma. None of the participants who took part in the study had been treated before or were eligible to receive stem-cell transplants. HOW WAS THE STUDY IN THIS SUMMARY CONDUCTED?: A total of 737 participants took part. Half of the participants took daratumumab plus lenalidomide and dexamethasone, while the other half of the participants took only lenalidomide and dexamethasone. Once participants started taking the drugs, the cancer was monitored for improvement (response to treatment), worsening (disease progression), or no change. Participants' blood and urine were tested for myeloma protein to measure response to the treatment. Participants were also monitored for side effects. WHAT WERE THE RESULTS OF THE STUDY?: After approximately 56 months of follow-up, more participants who took daratumumab plus lenalidomide and dexamethasone were alive and had decreased myeloma protein levels (indicating improvement of cancer) than participants who took only lenalidomide and dexamethasone. The most common side effects were abnormally low white and red blood cell counts and increased lung infections. WHAT DO THE RESULTS OF THE STUDY MEAN?: In the MAIA study, participants with multiple myeloma who took daratumumab plus lenalidomide and dexamethasone lived longer and had decreased myeloma protein levels than participants who took only lenalidomide and dexamethasone, indicating survival could be more likely with daratumumab added. Clinical Trial Registration: NCT02252172 (Phase 3 MAIA study).

Daratumumab plus Lenalidomide and Dexamethasone for Untreated Myeloma.

BACKGROUND: Lenalidomide plus dexamethasone is a standard treatment for patients with newly diagnosed multiple myeloma who are ineligible for autologous stem-cell transplantation. We sought to determine whether the addition of daratumumab would significantly reduce the risk of disease progression or death in this population. METHODS: We randomly assigned 737 patients with newly diagnosed multiple myeloma who were ineligible for autologous stem-cell transplantation to receive daratumumab plus lenalidomide and dexamethasone (daratumumab group) or lenalidomide and dexamethasone alone (control group). Treatment was to continue until the occurrence of disease progression or unacceptable side effects. The primary end point was progression-free survival. RESULTS: At a median follow-up of 28.0 months, disease progression or death had occurred in 240 patients (97 of 368 patients [26.4%] in the daratumumab group and 143 of 369 patients [38.8%] in the control group). The estimated percentage of patients who were alive without disease progression at 30 months was 70.6% (95% confidence interval [CI], 65.0 to 75.4) in the daratumumab group and 55.6% (95% CI, 49.5 to 61.3) in the control group (hazard ratio for disease progression or death, 0.56; 95% CI, 0.43 to 0.73; P<0.001). The percentage of patients with a complete response or better was 47.6% in the daratumumab group and 24.9% in the control group (P<0.001). A total of 24.2% of the patients in the daratumumab group, as compared with 7.3% of the patients in the control group, had results below the threshold for minimal residual disease (1 tumor cell per 105 white cells) (P<0.001). The most common adverse events of grade 3 or 4 were neutropenia (50.0% in the daratumumab group vs. 35.3% in the control group), anemia (11.8% vs. 19.7%), lymphopenia (15.1% vs. 10.7%), and pneumonia (13.7% vs. 7.9%). CONCLUSIONS: Among patients with newly diagnosed multiple myeloma who were ineligible for autologous stem-cell transplantation, the risk of disease progression or death was significantly lower among those who received daratumumab plus lenalidomide and dexamethasone than among those who received lenalidomide and dexamethasone alone. A higher incidence of neutropenia and pneumonia was observed in the daratumumab group. (Funded by Janssen Research and Development; MAIA ClinicalTrials.gov number, NCT02252172.).

Daratumumab, lenalidomide, and dexamethasone versus lenalidomide and dexamethasone alone in newly diagnosed multiple myeloma (MAIA): overall survival results from a randomised, open-label, phase 3 trial.

BACKGROUND: In the primary analysis of the phase 3 MAIA trial (median follow-up 28·0 months), a significant improvement in progression-free survival was observed with daratumumab plus lenalidomide and dexamethasone versus lenalidomide and dexamethasone alone in transplantation-ineligible patients with newly diagnosed multiple myeloma. Here, we report the updated efficacy and safety results from a prespecified interim analysis for overall survival. METHODS: MAIA is an ongoing, multicentre, randomised, open-label, phase 3 trial that enrolled patients at 176 hospitals in 14 countries across North America, Europe, the Middle East, and the Asia-Pacific region. Eligible patients were aged 18 years or older, had newly diagnosed multiple myeloma, had an Eastern Cooperative Oncology Group performance status score of 0-2, and were ineligible for high-dose chemotherapy with autologous stem-cell transplantation because of their age (≥65 years) or comorbidities. Patients were randomly assigned (1:1) using randomly permuted blocks (block size 4) by an interactive web response system to receive 28-day cycles of intravenous daratumumab (16 mg/kg, once per week during cycles 1-2, once every 2 weeks in cycles 3-6, and once every 4 weeks thereafter) plus oral lenalidomide (25 mg on days 1-21 of each cycle) and oral dexamethasone (40 mg on days 1, 8, 15, and 22 of each cycle; daratumumab group) or lenalidomide and dexamethasone alone (control group). Randomisation was stratified by International Staging System disease stage, geographical region, and age. Neither patients nor investigators were masked to treatment assignment. The primary endpoint was progression-free survival, which was centrally assessed, and a secondary endpoint was overall survival (both assessed in the intention-to-treat population). The safety population included patients who received at least one dose of the study treatment. The results presented here are from a prespecified interim analysis for overall survival, for which the prespecified stopping boundary was p=0·0414. This trial is registered with ClinicalTrials.gov, NCT02252172. FINDINGS: Between March 18, 2015, and Jan 15, 2017, 952 patients were assessed for eligibility, of whom 737 patients were enrolled and randomly assigned to the daratumumab group (n=368) or the control group (n=369). At a median follow-up of 56·2 months (IQR 52·7-59·9), median progression-free survival was not reached (95% CI 54·8-not reached) in the daratumumab group versus 34·4 months (29·6-39·2) in the control group (hazard ratio [HR] 0·53 [95% CI 0·43-0·66]; p<0·0001). Median overall survival was not reached in either group (daratumumab group, 95% CI not reached-not reached; control group, 95% CI 55·7-not reached; HR 0·68 [95% CI 0·53-0·86]; p=0·0013). The most common (>15%) grade 3 or higher treatment-emergent adverse events were neutropenia (197 [54%] patients in the daratumumab group vs 135 [37%] patients in the control group), pneumonia (70 [19%] vs 39 [11%]), anaemia (61 [17%] vs 79 [22%]), and lymphopenia (60 [16%] vs 41 [11%]). Serious adverse events occurred in 281 (77%) patients in the daratumumab group and 257 (70%) patients in the control group. Treatment-related deaths occurred in 13 (4%) patients in the daratumumab group and ten (3%) patients in the control group. INTERPRETATION: Daratumumab plus lenalidomide and dexamethasone increased overall survival and progression-free survival in patients ineligible for stem-cell transplantation with newly diagnosed multiple myeloma. There were no new safety concerns. Our results support the frontline use of daratumumab plus lenalidomide and dexamethasone for patients with multiple myeloma who are ineligible for transplantation. FUNDING: Janssen Research & Development.

Melflufen plus dexamethasone in relapsed/refractory multiple myeloma: long-term survival follow-up from the Phase II study O-12-M1.

An updated survival analysis was conducted for the Phase II study O-12-M1 of melphalan flufenamide (melflufen) plus dexamethasone in patients with relapsed/refractory multiple myeloma (RRMM) with two or more prior lines of therapy (including bortezomib and lenalidomide). Partial response or better was seen in 31%. After a 46-month median overall survival (OS) follow-up, melflufen plus dexamethasone had a median OS of 20·7 months (75th percentile OS, 47·5 months). The median time-to-next treatment for melflufen plus dexamethasone was 7·9 months. In summary, melflufen plus dexamethasone resulted in sustained long-term clinical benefit in patients with RRMM.

Health-related quality of life in patients with relapsed or refractory multiple myeloma: treatment with daratumumab, lenalidomide, and dexamethasone in the phase 3 POLLUX trial.

In the phase 3 POLLUX trial, daratumumab in combination with lenalidomide and dexamethasone (D-Rd) significantly improved progression-free survival in patients with relapsed/refractory multiple myeloma (RRMM) compared with lenalidomide and dexamethasone (Rd) alone. Here, we present patient-reported outcomes (PROs) from POLLUX, assessed using the validated European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30-item (EORTC QLQ-C30) and the EuroQol 5-dimensional descriptive system (EQ-5D-5L) questionnaires. Changes from baseline are presented as least-squares mean changes with 95% confidence intervals (CIs) derived from a mixed-effects model. PRO assessment compliance rates were high and similar in both D-Rd and Rd groups through cycle 40 (week 156). In this on-treatment analysis, mean changes from baseline were significantly greater in EORTC QLQ-C30 global health status, physical functioning, and pain scores in the D-Rd group versus the Rd group at multiple time points; however, magnitude of changes was low, suggesting no meaningful impact on health-related quality of life (HRQoL). Subgroup results were similar to those in the overall population. In the POLLUX study, baseline HRQoL was maintained with prolonged D-Rd treatment. These findings complement the sustained and significant improvement in progression-free survival observed with D-Rd and supports its use in patients with RRMM. Clinical trial registration: NCT02076009.

Subcutaneous delivery of daratumumab in relapsed or refractory multiple myeloma.

Daratumumab, a human monoclonal antibody targeting CD38, is approved as monotherapy and in combination regimens for patients with multiple myeloma (MM). Currently, daratumumab is administered IV. The phase 1b PAVO (MMY1004) study evaluated subcutaneously administered daratumumab in combination with the recombinant human hyaluronidase PH20 enzyme (rHuPH20) in patients with relapsed or refractory MM. Part 1 of the study, reported here, evaluated a mix-and-deliver (MD) formulation of daratumumab and rHuPH20 (DARA-MD) administered by subcutaneous infusion. Patients received subcutaneous daratumumab according to the approved IV monotherapy dosing schedule at 1200 mg (n = 8) or 1800 mg (n = 45). Primary end points were safety and pharmacokinetic (PK) variables. The most common treatment-emergent adverse events with DARA-MD 1200 mg were thrombocytopenia, upper respiratory tract infection, insomnia, and decreased appetite (37.5% each). Anemia (33.3%), upper respiratory tract infection, pyrexia, and diarrhea (26.7% each) were the most common treatment-emergent adverse events with DARA-MD 1800 mg. One patient in the 1200-mg dose group (12.5%) and 11 patients in the 1800-mg dose group (24.4%) experienced infusion-related reactions, which were generally grade 1/2 and typically occurred at the first infusion. The 1800 mg dose achieved similar or greater serum concentrations compared with the 16 mg/kg IV dose. Overall response rates of 25.0% and 42.2% were achieved with 1200-mg and 1800-mg DARA-MD, respectively. Subcutaneous administration of DARA-MD was well tolerated in patients with relapsed or refractory MM, with the 1800-mg dose exhibiting PK concentrations and responses consistent with IV daratumumab in a similar patient population. This study was registered at www.clinicaltrials.gov as #NCT02519452.

Subcutaneous daratumumab in patients with relapsed or refractory multiple myeloma: Part 2 of the open-label, multicenter, dose-escalation phase 1b study (PAVO).

Intravenous daratumumab is approved for the treatment of multiple myeloma. In Part 1 of the PAVO study, a mix-and-deliver subcutaneous formulation of daratumumab with recombinant human hyaluronidase PH20 (rHuPH20) was well tolerated, with low rates of infusion-related reactions and similar efficacy to intravenous daratumumab. Part 2 of PAVO evaluated a concentrated, pre-mixed co-formulation of daratumumab and rHuPH20 (DARA SC). Patients with ≥2 prior lines of therapy, including a proteasome inhibitor and immunomodulatory drug, received daratumumab (1800 mg) and rHuPH20 (30,000 U) in 15 mL subcutaneously over 3-5 minutes per the approved intravenous monotherapy dosing schedule. Primary endpoints were daratumumab trough concentration at the end of weekly dosing (just prior to the Cycle 3 Day 1 dose) and safety. Twenty-five patients were enrolled in PAVO Part 2. DARA SC achieved daratumumab trough concentrations similar to or greater than intravenous daratumumab 16 mg/kg. The adverse event profile of DARA SC was consistent with intravenous daratumumab, with no new safety concerns and a lower infusion-related reaction rate. At a median follow-up of 14.2 months, the overall response rate was 52%, median duration of response was 15.7 months, and median progression-free survival was 12.0 months. DARA SC 1800 mg was well tolerated in relapsed/refractory multiple myeloma, with a low infusion-related reaction rate and reduced administration time. Daratumumab serum concentrations following DARA SC were consistent with intravenous dosing, and deep and durable responses were observed. Based on these results, ongoing studies are investigating DARA SC in multiple myeloma and other conditions. (ClinicalTrials.gov identifier: 02519452).

Clinically-suspected cast nephropathy: A retrospective, national, real-world study.

Presentation with severe acute kidney injury due to cast nephropathy (CN) is a medical emergency in multiple myeloma (MM), with high risk of dialysis-dependent renal failure and death. Accrual of patients with CN into interventional studies is difficult, while phase III trials exclude patients with severe renal insufficiency. Real-world data are warranted. We assessed 2252 patients from the population-based Danish Multiple Myeloma Registry (DMMR) who were diagnosed between 2013 and 2017. We identified 204 patients with clinically-suspected CN, defined as serum creatinine concentration >177 µmol/L and serum free light chain (sFLC) concentration >1000 mg/L at the time of diagnosis. The median age was 72 years. Thirty-one percent of patients presented with dialysis-dependent renal failure. Kidney biopsies were performed in 19% of patients and showed CN in 74% of cases. Despite prompt initiation of bortezomib-based therapy in 94% of patients, 33% of patients died in the first year after diagnosis. Compared with the rest of the patients in the DMMR with symptomatic MM, patients with clinically-suspected CN had worse overall survival (OS) irrespective of transplant eligibility. Achievement of renal recovery was associated with deep reductions of involved sFLC. Achievement of very good partial response or better in the first line of therapy and/or deep reduction of involved sFLC at 3 months after initiation of therapy were associated with superior OS. In conclusion, MM patients presenting with clinically-suspected CN have an alarmingly high one-year mortality when treated with current standards of care. Early and deep hematologic response is crucial for survival.

Daratumumab, Lenalidomide, and Dexamethasone for Multiple Myeloma.

BACKGROUND: Daratumumab showed promising efficacy alone and with lenalidomide and dexamethasone in a phase 1-2 study involving patients with relapsed or refractory multiple myeloma. METHODS: In this phase 3 trial, we randomly assigned 569 patients with multiple myeloma who had received one or more previous lines of therapy to receive lenalidomide and dexamethasone either alone (control group) or in combination with daratumumab (daratumumab group). The primary end point was progression-free survival. RESULTS: At a median follow-up of 13.5 months in a protocol-specified interim analysis, 169 events of disease progression or death were observed (in 53 of 286 patients [18.5%] in the daratumumab group vs. 116 of 283 [41.0%] in the control group; hazard ratio, 0.37; 95% confidence interval [CI], 0.27 to 0.52; P<0.001 by stratified log-rank test). The Kaplan-Meier rate of progression-free survival at 12 months was 83.2% (95% CI, 78.3 to 87.2) in the daratumumab group, as compared with 60.1% (95% CI, 54.0 to 65.7) in the control group. A significantly higher rate of overall response was observed in the daratumumab group than in the control group (92.9% vs. 76.4%, P<0.001), as was a higher rate of complete response or better (43.1% vs. 19.2%, P<0.001). In the daratumumab group, 22.4% of the patients had results below the threshold for minimal residual disease (1 tumor cell per 105 white cells), as compared with 4.6% of those in the control group (P<0.001); results below the threshold for minimal residual disease were associated with improved outcomes. The most common adverse events of grade 3 or 4 during treatment were neutropenia (in 51.9% of the patients in the daratumumab group vs. 37.0% of those in the control group), thrombocytopenia (in 12.7% vs. 13.5%), and anemia (in 12.4% vs. 19.6%). Daratumumab-associated infusion-related reactions occurred in 47.7% of the patients and were mostly of grade 1 or 2. CONCLUSIONS: The addition of daratumumab to lenalidomide and dexamethasone significantly lengthened progression-free survival among patients with relapsed or refractory multiple myeloma. Daratumumab was associated with infusion-related reactions and a higher rate of neutropenia than the control therapy. (Funded by Janssen Research and Development; POLLUX ClinicalTrials.gov number, NCT02076009 .).

High-Parameter Mass Cytometry Evaluation of Relapsed/Refractory Multiple Myeloma Patients Treated with Daratumumab Demonstrates Immune Modulation as a Novel Mechanism of Action.

Daratumumab is a CD38-targeted human monoclonal antibody with direct anti-myeloma cell mechanisms of action. Flow cytometry in relapsed and/or refractory multiple myeloma (RRMM) patients treated with daratumumab revealed cytotoxic T-cell expansion and reduction of immune-suppressive populations, suggesting immune modulation as an additional mechanism of action. Here, we performed an in-depth analysis of the effects of daratumumab on immune-cell subpopulations using high-dimensional mass cytometry. Whole-blood and bone-marrow baseline and on-treatment samples from RRMM patients who participated in daratumumab monotherapy studies (SIRIUS and GEN501) were evaluated with high-throughput immunophenotyping. In daratumumab-treated patients, the intensity of CD38 marker expression decreased on many immune cells in SIRIUS whole-blood samples. Natural killer (NK) cells were depleted with daratumumab, with remaining NK cells showing increased CD69 and CD127, decreased CD45RA, and trends for increased CD25, CD27, and CD137 and decreased granzyme B. Immune-suppressive population depletion paralleled previous findings, and a newly observed reduction in CD38+ basophils was seen in patients who received monotherapy. After 2 months of daratumumab, the T-cell population in whole-blood samples from responders shifted to a CD8 prevalence with higher granzyme B positivity (P = 0.017), suggesting increased killing capacity and supporting monotherapy-induced CD8+ T-cell activation. High-throughput cytometry immune profiling confirms and builds upon previous flow cytometry data, including comparable CD38 marker intensity on plasma cells, NK cells, monocytes, and B/T cells. Interestingly, a shift toward cytolytic granzyme B+ T cells was also observed and supports adaptive responses in patients that may contribute to depth of response. © 2018 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.

Targeting CD38 with Daratumumab Monotherapy in Multiple Myeloma.

BACKGROUND: Multiple myeloma cells uniformly overexpress CD38. We studied daratumumab, a CD38-targeting, human IgG1κ monoclonal antibody, in a phase 1-2 trial involving patients with relapsed myeloma or relapsed myeloma that was refractory to two or more prior lines of therapy. METHODS: In part 1, the dose-escalation phase, we administered daratumumab at doses of 0.005 to 24 mg per kilogram of body weight. In part 2, the dose-expansion phase, 30 patients received 8 mg per kilogram of daratumumab and 42 received 16 mg per kilogram, administered once weekly (8 doses), twice monthly (8 doses), and monthly for up to 24 months. End points included safety, efficacy, and pharmacokinetics. RESULTS: No maximum tolerated dose was identified in part 1. In part 2, the median time since diagnosis was 5.7 years. Patients had received a median of four prior treatments; 79% of the patients had disease that was refractory to the last therapy received (64% had disease refractory to proteasome inhibitors and immunomodulatory drugs and 64% had disease refractory to bortezomib and lenalidomide), and 76% had received autologous stem-cell transplants. Infusion-related reactions in part 2 were mild (71% of patients had an event of any grade, and 1% had an event of grade 3), with no dose-dependent adverse events. The most common adverse events of grade 3 or 4 (in ≥ 5% of patients) were pneumonia and thrombocytopenia. The overall response rate was 36% in the cohort that received 16 mg per kilogram (15 patients had a partial response or better, including 2 with a complete response and 2 with a very good partial response) and 10% in the cohort that received 8 mg per kilogram (3 had a partial response). In the cohort that received 16 mg per kilogram, the median progression-free survival was 5.6 months (95% confidence interval [CI], 4.2 to 8.1), and 65% (95% CI, 28 to 86) of the patients who had a response did not have progression at 12 months. CONCLUSIONS: Daratumumab monotherapy had a favorable safety profile and encouraging efficacy in patients with heavily pretreated and refractory myeloma. (Funded by Janssen Research and Development and Genmab; ClinicalTrials.gov number, NCT00574288.).

Clinical efficacy of daratumumab monotherapy in patients with heavily pretreated relapsed or refractory multiple myeloma.

The efficacy and favorable safety profile of daratumumab monotherapy in multiple myeloma (MM) was previously reported. Here, we present an updated pooled analysis of 148 patients treated with daratumumab 16 mg/kg. Data were combined from part 2 of a first-in-human phase 1/2 study of patients who relapsed after or were refractory to ≥2 prior therapies and a phase 2 study of patients previously treated with ≥3 prior lines of therapy (including a proteasome inhibitor [PI] and an immunomodulatory drug [IMiD]) or were double refractory. Among the pooled population, patients received a median of 5 prior lines of therapy (range, 2 to 14 prior lines of therapy), and 86.5% were double refractory to a PI and an IMiD. Overall response rate was 31.1%, including 13 very good partial responses, 4 complete responses, and 3 stringent complete responses. The median duration of response was 7.6 months (95% confidence interval [CI], 5.6 to not evaluable [NE]). The median progression-free survival (PFS) and overall survival (OS) were 4.0 months (95% CI, 2.8-5.6 months) and 20.1 months (95% CI, 16.6 months to NE), respectively. When stratified by responders vs stable disease/minimal response vs progressive disease/NE, median PFS was 15.0 months (95% CI, 7.4 months to NE) vs 3.0 months (95% CI, 2.8-3.7 months) vs 0.9 months (95% CI, 0.9-1.0 months), respectively, and median OS was NE (95% CI, NE to NE) vs 18.5 months (95% CI, 15.1-22.4 months) vs 3.7 months (95% CI, 1.7-7.6 months), respectively. No new safety signals were identified. In this pooled data set, daratumumab 16 mg/kg monotherapy demonstrated rapid, deep, and durable responses, with a clinical benefit that extended to patients with stable disease or better.

Daratumumab depletes CD38+ immune regulatory cells, promotes T-cell expansion, and skews T-cell repertoire in multiple myeloma.

Daratumumab targets CD38-expressing myeloma cells through a variety of immune-mediated mechanisms (complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, and antibody-dependent cellular phagocytosis) and direct apoptosis with crosslinking. These mechanisms may also target nonplasma cells that express CD38, which prompted evaluation of daratumumab's effects on CD38-positive immune subpopulations. Peripheral blood (PB) and bone marrow (BM) from patients with relapsed/refractory myeloma from 2 daratumumab monotherapy studies were analyzed before and during therapy and at relapse. Regulatory B cells and myeloid-derived suppressor cells, previously shown to express CD38, were evaluated for immunosuppressive activity and daratumumab sensitivity in the myeloma setting. A novel subpopulation of regulatory T cells (Tregs) expressing CD38 was identified. These Tregs were more immunosuppressive in vitro than CD38-negative Tregs and were reduced in daratumumab-treated patients. In parallel, daratumumab induced robust increases in helper and cytotoxic T-cell absolute counts. In PB and BM, daratumumab induced significant increases in CD8(+):CD4(+) and CD8(+):Treg ratios, and increased memory T cells while decreasing naïve T cells. The majority of patients demonstrated these broad T-cell changes, although patients with a partial response or better showed greater maximum effector and helper T-cell increases, elevated antiviral and alloreactive functional responses, and significantly greater increases in T-cell clonality as measured by T-cell receptor (TCR) sequencing. Increased TCR clonality positively correlated with increased CD8(+) PB T-cell counts. Depletion of CD38(+) immunosuppressive cells, which is associated with an increase in T-helper cells, cytotoxic T cells, T-cell functional response, and TCR clonality, represents possible additional mechanisms of action for daratumumab and deserves further exploration.

Clinical efficacy and management of monoclonal antibodies targeting CD38 and SLAMF7 in multiple myeloma.

Immunotherapeutic strategies are emerging as promising therapeutic approaches in multiple myeloma (MM), with several monoclonal antibodies in advanced stages of clinical development. Of these agents, CD38-targeting antibodies have marked single agent activity in extensively pretreated MM, and preliminary results from studies with relapsed/refractory patients have shown enhanced therapeutic efficacy when daratumumab and isatuximab are combined with other agents. Furthermore, although elotuzumab (anti-SLAMF7) has no single agent activity in advanced MM, randomized trials in relapsed/refractory MM have demonstrated significantly improved progression-free survival when elotuzumab is added to lenalidomide-dexamethasone or bortezomib-dexamethasone. Importantly, there has been no significant additive toxicity when these monoclonal antibodies are combined with other anti-MM agents, other than infusion-related reactions specific to the therapeutic antibody. Prevention and management of infusion reactions is important to avoid drug discontinuation, which may in turn lead to reduced efficacy of anti-MM therapy. Therapeutic antibodies interfere with several laboratory tests. First, interference of therapeutic antibodies with immunofixation and serum protein electrophoresis assays may lead to underestimation of complete response. Strategies to mitigate interference, based on shifting the therapeutic antibody band, are in development. Furthermore, daratumumab, and probably also other CD38-targeting antibodies, interfere with blood compatibility testing and thereby complicate the safe release of blood products. Neutralization of the therapeutic CD38 antibody or CD38 denaturation on reagent red blood cells mitigates daratumumab interference with transfusion laboratory serologic tests. Finally, therapeutic antibodies may complicate flow cytometric evaluation of normal and neoplastic plasma cells, since the therapeutic antibody can affect the availability of the epitope for binding of commercially available diagnostic antibodies.

Phase 1/2 study of daratumumab, lenalidomide, and dexamethasone for relapsed multiple myeloma.

Daratumumab, a human CD38 immunoglobulin G1 kappa (IgG1κ) monoclonal antibody, has activity as monotherapy in multiple myeloma (MM). This phase 1/2 study investigated daratumumab plus lenalidomide/dexamethasone in refractory and relapsed/refractory MM. Part 1 (dose escalation) evaluated 4 daratumumab doses plus lenalidomide (25 mg/day orally on days 1-21 of each cycle) and dexamethasone (40 mg/week). Part 2 (dose expansion) evaluated daratumumab at the recommended phase 2 dose (RP2D) plus lenalidomide/dexamethasone. Safety, efficacy, pharmacokinetics, immunogenicity, and accelerated daratumumab infusions were studied. In part 1 (13 patients), no dose-limiting toxicities were observed, and 16 mg/kg was selected as the R2PD. In part 2 (32 patients), median time since diagnosis was 3.2 years, with a median of 2 prior therapies (range, 1-3 prior therapies), including proteasome inhibitors (91%), alkylating agents (91%), autologous stem cell transplantation (78%), thalidomide (44%), and lenalidomide (34%); 22% of patients were refractory to the last line of therapy. Grade 3 to 4 adverse events (≥5%) included neutropenia, thrombocytopenia, and anemia. In part 2, infusion-related reactions (IRRs) occurred in 18 patients (56%); most were grade ≤2 (grade 3, 6.3%). IRRs predominantly occurred during first infusions and were more common during accelerated infusions. In part 2 (median follow-up of 15.6 months), overall response rate was 81%, with 8 stringent complete responses (25%), 3 complete responses (9%), and 9 very good partial responses (28%). Eighteen-month progression-free and overall survival rates were 72% (95% confidence interval, 51.7-85.0) and 90% (95% confidence interval, 73.1-96.8), respectively. Daratumumab plus lenalidomide/dexamethasone resulted in rapid, deep, durable responses. The combination was well tolerated and consistent with the safety profiles observed with lenalidomide/dexamethasone or daratumumab monotherapy. This trial was registered at www.clinicaltrials.gov as #NCT01615029.

Melphalan, prednisone, and lenalidomide versus melphalan, prednisone, and thalidomide in untreated multiple myeloma.

The combination of melphalan, prednisone, and thalidomide (MPT) is considered standard therapy for newly diagnosed patients with multiple myeloma who are ineligible for stem cell transplantation. Long-term treatment with thalidomide is hampered by neurotoxicity. Melphalan, prednisone, and lenalidomide, followed by lenalidomide maintenance therapy, showed promising results without severe neuropathy emerging. We randomly assigned 668 patients between nine 4-week cycles of MPT followed by thalidomide maintenance until disease progression or unacceptable toxicity (MPT-T) and the same MP regimen with thalidomide being replaced by lenalidomide (MPR-R). This multicenter, open-label, randomized phase 3 trial was undertaken by Dutch-Belgium Cooperative Trial Group for Hematology Oncology and the Nordic Myeloma Study Group (the HOVON87/NMSG18 trial). The primary end point was progression-free survival (PFS). A total of 318 patients were randomly assigned to receive MPT-T, and 319 received MPR-R. After a median follow-up of 36 months, PFS with MPT-T was 20 months (95% confidence interval [CI], 18-23 months) vs 23 months (95% CI, 19-27 months) with MPR-R (hazard ratio, 0.87; 95% CI, 0.72-1.04; P = .12). Response rates were similar, with at least a very good partial response of 47% and 45%, respectively. Hematologic toxicity was more pronounced with MPR-R, especially grades 3 and 4 neutropenia: 64% vs 27%. Neuropathy of at least grade 3 was significantly higher in the MPT-T arm: 16% vs 2% in MPR-R, resulting in a significant shorter duration of maintenance therapy (5 vs 17 months in MPR-R), irrespective of age. MPR-R has no advantage over MPT-T concerning efficacy. The toxicity profile differed with clinically significant neuropathy during thalidomide maintenance vs myelosuppression with MPR.

Effects of single-agent bortezomib as post-transplant consolidation therapy on multiple myeloma-related bone disease: a randomized phase II study.

This phase II study explored the effects of bortezomib consolidation versus observation on myeloma-related bone disease in patients who had a partial response or better after frontline high-dose therapy and autologous stem cell transplantation. Patients were randomized to receive four 35-day cycles of bortezomib 1·6 mg/m2 intravenously on days 1, 8, 15 and 22, or an equivalent observation period, and followed up for disease status/survival. The modified intent-to-treat population included 104 patients (51 bortezomib, 53 observation). There were no meaningful differences in the primary endpoint of change from baseline to end of treatment in bone mineral density (BMD). End-of-treatment rates (bortezomib versus observation) of complete response/stringent complete response were 22% vs. 11% (P = 0·19), very good partial response or better of 80% vs. 68% (P = 0·17), and progressive disease of 8% vs. 23% (P = 0·06); median progression-free survival was 44·9 months vs. 21·8 months (P = 0·22). Adverse events observed ≥15% more frequently with bortezomib versus observation were diarrhoea (37% vs. 0), peripheral sensory neuropathy (20% vs. 4%), nausea (18% vs. 0) and vomiting (16% vs. 0). Compared with observation, bortezomib appeared to have little impact on bone metabolism/health, but was associated with trends for improved myeloma response and survival.

First-line chemoimmunotherapy with bendamustine and rituximab versus fludarabine, cyclophosphamide, and rituximab in patients with advanced chronic lymphocytic leukaemia (CLL10): an international, open-label, randomised, phase 3, non-inferiority trial.

BACKGROUND: Chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab is the standard therapy for physically fit patients with advanced chronic lymphocytic leukaemia. This international phase 3 study compared the efficacy and tolerance of the standard therapy with a potentially less toxic combination consisting of bendamustine and rituximab. METHODS: Treatment-naive fit patients with chronic lymphocytic leukaemia (aged 33-81 years) without del(17p) were enrolled after undergoing a central screening process. Patients were randomly assigned (1:1) with a computer-generated randomisation list using randomly permuted blocks with a block size of eight and were stratified according to participating country and Binet stage. Patients were allocated to receive six cycles of intravenous fludarabine (25 mg/m(2) per day) and cyclophosphamide (250 mg/m(2) per day) for the first 3 days or to intravenous bendamustine (90 mg/m(2) per day) for the first 2 days of each cycle. Rituximab 375 mg/m(2) was given intravenously in both groups on day 0 of cycle 1 and subsequently was given at 500 mg/m(2) during the next five cycles on day 1. The primary endpoint was progression-free survival with the objective to assess non-inferiority of bendamustine and rituximab to the standard therapy. We aimed to show that the 2-year progression-free survival with bendamustine and rituximab was not 67·5% or less with a corresponding non-inferiority margin of 1·388 for the hazard ratio (HR) based on the 90·4% CI. The final analysis was done by intention to treat. The study is registered with ClinicalTrials.gov, number NCT%2000769522. FINDINGS: 688 patients were recruited between Oct 2, 2008, and July 11, 2011, of which 564 patients who met inclusion criteria were randomly assigned. 561 patients were included in the intention-to-treat population: 282 patients in the fludarabine, cyclophosphamide, and rituximab group and 279 in the bendamustine and rituximab group. After a median observation time of 37·1 months (IQR 31·0-45·5) median progression-free survival was 41·7 months (95% CI 34·9-45·3) with bendamustine and rituximab and 55·2 months (95% CI not evaluable) with fludarabine, cyclophosphamide, and rituximab (HR 1·643, 90·4% CI 1·308-2·064). As the upper limit of the 90·4% CI was greater than 1·388 the null hypothesis for the corresponding non-inferiority hypothesis was not rejected. Severe neutropenia and infections were more frequently observed with fludarabine, cyclophosphamide, and rituximab (235 [84%] of 279 vs 164 [59%] of 278, and 109 [39%] vs 69 [25%], respectively) during the study. The increased frequency of infectious complications with fludarabine, cyclophosphamide, and rituximab was more pronounced in patients older than 65 years. INTERPRETATION: The combination of fludarabine, cyclophosphamide, and rituximab remains the standard front-line therapy in fit patients with chronic lymphocytic leukaemia, but bendamustine and rituximab is associated with less toxic effects. FUNDING: Roche Pharma AG, Mundipharma, German Federal Ministry of Education and Research.

Multiplex polymerase chain reaction-based prognostic models in diffuse large B-cell lymphoma patients treated with R-CHOP.

We present a multiplex analysis for genes known to have prognostic value in an attempt to design a clinically useful classification model in patients with diffuse large B-cell lymphoma (DLBCL). Real-time polymerase chain reaction was used to measure transcript levels of 28 relevant genes in 194 de novo DLBCL patients treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone). Including International Prognostic Index (IPI) as a variable in a penalized Cox regression, we investigated the association with disease progression for single genes or gene combinations in four models. The best model was validated in data from an online available R-CHOP treated cohort. With progression-free survival (PFS) as primary endpoint, the best performing IPI independent model incorporated the LMO2 and HLADQA1 as well as gene interactions for GCSAMxMIB1, GCSAMxCTGF and FOXP1xPDE4B. This model assigned 33% of patients (n = 60) to poor outcome with an estimated 3-year PFS of 40% vs. 87% for low risk (n = 61) and intermediate (n = 60) risk groups (P < 0·001). However, a simpler, IPI independent model incorporated LMO2 and BCL2 and assigned 33% of the patients with a 3-year PFS of 35% vs. 82% for low risk group (P < 0·001). We have documented the impact of a few single genes added to IPI for assignment in new drug trials.