Idecabtagene vicleucel for relapsed and refractory multiple myeloma: post hoc 18-month follow-up of a phase 1 trial.

Idecabtagene vicleucel (ide-cel) is a B-cell-maturation antigen (BCMA)-directed chimeric antigen receptor T cell therapy. We performed a post hoc analysis of a single-arm phase 1 multicenter study in relapsed/refractory multiple myeloma (CRB-401) (n = 62; median follow-up, 18.1 months). The primary endpoint was safety outcomes, and secondary endpoints included overall response rate (ORR), complete response (CR) and very good partial response (VGPR). The study met its primary endpoint with low rates of grade 3/grade 4 cytokine release syndrome (6.5%) and neurotoxicity (1.6%). ORR was 75.8%; 64.5% achieved VGPR or better and 38.7% achieved CR or stringent CR. Among exploratory endpoints, median duration of response, progression-free survival (PFS) and overall survival were 10.3, 8.8 and 34.2 months, respectively, and ide-cel expansion in blood and bone marrow correlated with clinical efficacy and postinfusion reduction of soluble BCMA. Patients with PFS ≥ 18 months had more naive and less exhausted T cells in apheresis material and improved functional T cell phenotype in the drug product compared with those with less durable responses. These results confirm ide-cel safety, tolerability and efficacy and describe T cell qualities that correlate with durable response. Clinicaltrials.gov identifier : NCT02658929 .

Inhibition of NF-κB DNA Binding Suppresses Myeloma Growth via Intracellular Redox and Tumor Microenvironment Modulation.

Multiple myeloma is a plasma cell malignancy that is still largely incurable, despite considerable progress in recent years. NF-κB is a well-established therapeutic target in multiple myeloma, but none of the currently available treatment options offer direct, specific pharmacologic targeting of NF-κB transcriptional activity. Thus, we designed a novel direct NF-κB inhibitor (IT848) as a drug candidate with strong potential for clinical translation and conducted comprehensive in vitro and in vivo mechanistic studies in multiple myeloma cell lines, primary multiple myeloma cells, xenograft models, and immunocompetent mouse models of multiple myeloma. Here, we show that IT848 inhibits NF-κB activity through inhibition of DNA binding of all five NF-κB subunits. IT848 treatment of multiple myeloma cell lines and patient samples inhibited proliferation and induced caspase-dependent and independent apoptosis. In addition to direct NF-κB inhibitory effects, IT848 treatment altered the redox homeostasis of multiple myeloma cells through depletion of the reduced glutathione pool, selectively inducing oxidative stress in multiple myeloma but not in healthy cells. Multiple myeloma xenograft studies confirmed the efficacy of IT848 as single agent and in combination with bortezomib. Furthermore, IT848 significantly improved survival when combined with programmed death protein 1 inhibition, and correlative immune studies revealed that this clinical benefit was associated with suppression of regulatory T-cell infiltration of the bone marrow microenvironment. In conclusion, IT848 is a potent direct NF-κB inhibitor and inducer of oxidative stress specifically in tumor cells, displaying significant activity against multiple myeloma cells in vitro and in vivo, both as monotherapy as well as in combination with bortezomib or immune checkpoint blockade.

Natural killer cells activity against multiple myeloma cells is modulated by osteoblast-induced IL-6 and IL-10 production.

Background: Natural killer (NK) cells are part of the innate arm of the immune system; as such NK cells can be activated rapidly to target virus-infected cells and tumor cells without prior sensitization. The human NK-92MI cell line is among the most widely used NK cell in preclinical research studies and has also been approved for clinical applications. Previous studies have shown that osteoblasts (OSB) confer drug resistance in multiple myeloma (MM) and other cancers that metastasize to the bone marrow. Aim: We evaluated here how OSB, which are bone forming cells and a key cellular component of the bone marrow microenvironment, modulate the cytotoxic activity of NK-92MI cells against the MM.1S multiple myeloma cell line. Methods: The osteoblastic niche was recapitulated with either the osteoblastic cell line hFOB 1.19 (hFOB) or primary osteoblasts (P-OSB) derived from surgical resections. Time-lapse imaging was utilized to quantify changes in MM.1S cell viability under different conditions, including: (1) Co-culture of MM.1S with NK92MI cells, (2) triple-culture of hFOB or P-OSB with MM.1S and NK-92MI, and (3) MM.1S or NK-92MI cells primed with OSB-derived supernatant. Cytokine analysis was conducted to quantify potential secreted factors associated with the protective effects of OSB. Results: The physical presence of OSB hindered the activity of NK-92MI cells, resulting in the increased viability of MM.1S compared to co-cultures which lacked OSB. This observation was accompanied by reduced perforin and granzyme A secretion from NK-92MI cells. Contact of OSB and NK-92MI cells also induced interleukin 6 (IL-6) and interleukin 10 (IL-10) production; two cytokines which are known to impair the NK cell immunity against MM and other cancers. OSB supernatant also conferred cytoprotection to MM.1S, suggesting a dual mechanism by which OSB may modulate both NK and MM cells. Conclusions: We demonstrated here that OSB can negatively impact the activity of NK cells against MM. As NK cells and their chimeric antigen receptor-modified versions become more widely used in the clinic, our results suggest that understanding the role of OSB as potential immunoregulators of the NK cell-mediated cytotoxic response in the bone marrow tumor microenvironment may provide new opportunities for enhancing the effectiveness of this potent immunotherapeutic approach.

Preferences and Priorities for Relapsed Multiple Myeloma Treatments Among Patients and Caregivers in the United States.

Introduction/Background: This study aimed to describe patient and caregiver preferences for treatments of relapsed or refractory multiple myeloma (MM). Materials and Methods: A survey including discrete-choice experiment (DCE) and best-worst scaling (BWS) exercises was conducted among US patients with relapsed or refractory MM and their caregivers. The DCE included six attributes with varying levels including progression-free survival (PFS), toxicity, and mode and frequency of administration. In addition, the impact of treatment cost was assessed using a fixed-choice question. The BWS exercise included 18 items (modes and frequency of administration, additional treatment convenience, and toxicity items). The survey was administered online to patients recruited from the Multiple Myeloma Research Foundation CoMMpass study (NCT01454297). Results: The final samples consisted of 94 patients and 32 caregivers. Avoiding severe nerve damage was most important to patients, followed by longer PFS. Caregivers considered PFS to be the most important attribute. We estimate that a third or more of patients were cost-sensitive, meaning their treatment preference was altered based on cost implications. Caregivers were not cost-sensitive. The three most bothersome treatment features in the BWS exercise were risk of kidney failure, lowering white blood cell counts, and weakening the immune system. Conclusion: Patients with relapsed or refractory MM and their caregivers consider many factors including efficacy, toxicity, mode/frequency of administration, and cost in their decisions regarding treatment options. The study provides a basis for future Research on patient and caregiver treatment preferences, which could be incorporated into shared decision-making with physicians.

Sustained Hematopoietic Engraftment Potential after Prolonged Storage of Cryopreserved Hematopoietic Stem Cells Used in Salvage Autologous Stem Cell Transplantation.

Salvage autologous hematopoietic stem cell transplantation (HSCT) is an effective treatment for patients with relapsed multiple myeloma (MM). Peripheral blood stem cells (PBSCs), a source of hematopoietic stem cells (HSCs), are collected before the first transplantation, and adequate quantities of PBSCs can be collected and stored potentially for years to support at least 2 transplantations for eligible patients. To ensure the safety of salvage HSCT in the treatment of patients in subsequent relapse, PBSCs must retain the potential to engraft even after several years of cryopreservation. Although PBSC viability has been studied extensively using in vitro techniques, few publications describe the most rigorous functional potency measure, of patients receiving a myeloablative conditioning regimen. This study describes a large single-institution experience evaluating the engraftment kinetics of PBSCs used in salvage transplantation after multiple years of storage compared with first transplantation for the same patients in the treatment of MM. A retrospective chart review of patients with MM undergoing HSCT between 2000 and 2021 identified 89 patients who received salvage autologous PBSCs stored for >1 year after first HSCT. PBSCs were cryopreserved and stored in vapor-phase liquid nitrogen refrigerators at ≤-150°C. All patients received a PBSC product from the same collection cycle for both transplantations. Differences in CD34+ cell doses and days to engraftment between the first and salvage transplantations were tested using the paired 2-tailed t-test and Wilcoxon signed-rank test. Univariate and multivariable linear regressions were used to determine the association between storage time and days to engraftment, adjusting for CD34+ cell dose and conditioning regimen in the multivariable model. The median duration of storage between the day of initial collection and salvage transplant was 5.4 years (range, 1.0 to 19.7 years). Engraftment kinetics demonstrated a sustained neutrophil engraftment (absolute neutrophil count >0.5 × 109 cells/L) at a median of 11 days after both the first and salvage transplantations (range, 8 to 15 days and 8 to 19 days, respectively; P < .05). The median time to sustained platelet engraftment (>20 × 109 cells/L without transfusion support) was 13.5 days after the first HSCT and 14 days after salvage HSCT (range, 9 to 27 days and 10 to 56 days, respectively; P = .616). After adjusting for CD34+ cell doses and conditioning regimens, there was no association between the duration of cryopreservation and days to neutrophil engraftment (r = 0.178, P = .130) or platelet engraftment (r = 0.244, P = .100). Engraftment kinetics of the salvage HSCT are comparable to those of the first HSCT even when products are stored in vapor-phase nitrogen refrigerators for a median of 5.4 years. There is no association between the duration of storage and time to engraftment when controlling for CD34+ cell dose and conditioning regimen. Prolonged storage of cryopreserved HSC products is a safe practice for MM patients undergoing salvage autologous HSCT.

Pomalidomide, dexamethasone, and daratumumab immediately after lenalidomide-based treatment in patients with multiple myeloma: updated efficacy, safety, and health-related quality of life results from the phase 2 MM-014 trial.

Patients with relapsed/refractory multiple myeloma (RRMM) need proven subsequent therapies after early-line lenalidomide treatment failure. The phase 2 MM-014 trial (NCT01946477) investigated pomalidomide, dexamethasone, and daratumumab after 1 to 2 prior treatment lines (62.5%, 1 prior line) in patients with RRMM and prior lenalidomide (75.0%, lenalidomide refractory). With a median follow-up of 28.4 months, overall response rate was 77.7% (52.7% achieved very good partial response or better) and median progression-free survival was 30.8 months. For patients with lenalidomide-refractory disease, these outcomes were 76.2%, 47.6%, and 23.7 months, respectively. No new safety signals were observed; 64.3% experienced grade 3/4 neutropenia. Health-related quality of life was preserved or trended toward improvement through 12 treatment cycles. Pomalidomide, dexamethasone, and daratumumab given immediately after early-line lenalidomide-based treatment continues to demonstrate safety and efficacy, supporting pomalidomide-dexamethasone as a foundation of combination therapy in RRMM and providing evidence that the immunomodulatory agent class delivers benefit after lenalidomide treatment failure.

Indatuximab ravtansine plus dexamethasone with lenalidomide or pomalidomide in relapsed or refractory multiple myeloma: a multicentre, phase 1/2a study.

BACKGROUND: Indatuximab ravtansine (BT062) is an antibody-drug conjugate that binds to CD138 and synergistically enhances the antitumor activity of lenalidomide in preclinical models of multiple myeloma. This phase 1/2a study was done to determine the safety, activity, and pharmacokinetics of indatuximab ravtansine in combination with immunomodulatory drugs in patients with relapsed or refractory multiple myeloma. METHODS: This open-label, phase 1/2a study took place at nine hospital sites in the USA. Eligible patients were aged 18 years or older, had relapsed or refractory multiple myeloma, and ECOG performance status or Zubrod score of 2 or below. Patients who received indatuximab ravtansine with lenalidomide and dexamethasone (indatuximab ravtansine plus lenalidomide) had failure of at least one previous therapy. Patients treated with indatuximab ravtansine with pomalidomide and dexamethasone (indatuximab ravtansine plus pomalidomide) had failure of at least two previous therapies (including lenalidomide and bortezomib) and had progressive disease on or within 60 days of completion of their last treatment. In phase 1, patients received indatuximab ravtansine intravenously on days 1, 8, and 15 of each 28-day cycle in escalating dose levels of 80 mg/m2, 100 mg/m2, and 120 mg/m2, with lenalidomide (25 mg; days 1 to 21 every 28 days orally) and dexamethasone (20-40 mg; days 1, 8, 15, and 22 every 28 days). In phase 2, the recommended phase 2 dose of indatuximab ravtansine was given to an expanded cohort of patients in combination with lenalidomide and dexamethasone. The protocol was amended to allow additional patients to be treated with indatuximab ravtansine plus pomalidomide (4 mg; days 1 to 21 every 28 days orally) and dexamethasone, in a more heavily pretreated patient population than in the indatuximab ravtansine plus lenalidomide group. The phase 1 primary endpoint was to determine the dose-limiting toxicities and the maximum tolerated dose (recommended phase 2 dose) of indatuximab ravtansine, and the phase 2 primary endpoint was to describe the objective response rate (ORR; partial response or better) and clinical benefit response (ORR plus minor response). All patients were analysed for safety and all patients with post-treatment response assessments were analysed for activity. This study is registered with ClinicalTrials.gov, number NCT01638936, and is complete. FINDINGS: 64 (86%) of 74 screened patients were enrolled between July 3, 2012, and June 30, 2015. 47 (73%) patients received indatuximab ravtansine plus lenalidomide (median follow-up 24·2 months [IQR 19·9-45·4]) and 17 (27%) received indatuximab ravtansine plus pomalidomide (24·1 months [17·7-36·7]). The maximum tolerated dose of indatuximab ravtansine plus lenalidomide was 100 mg/m2, and defined as the recommended phase 2 dose for indatuximab ravtansine plus pomalidomide. An objective response for indatuximab ravtansine plus lenalidomide was observed in 33 (71·7%) of 46 patients and in 12 (70·6%) of 17 patients in the indatuximab ravtansine plus pomalidomide group. The clinical benefit response for indatuximab ravtansine plus lenalidomide was 85% (39 of 46 patients) and for indatuximab ravtansine plus pomalidomide it was 88% (15 of 17 patients). The most common grade 3-4 adverse events in both groups were neutropenia (14 [22%] of 64 patients), anaemia (10 [16%]), and thrombocytopenia (seven [11%]). Treatment-emergent adverse events (TEAEs) that led to discontinuation occurred in 35 (55%) of the 64 patients. Five (8%) patients with a TEAE had a fatal outcome; none was reported as related to indatuximab ravtansine. INTERPRETATION: Indatuximab ravtansine in combination with immunomodulatory drugs shows preliminary antitumor activity, is tolerated, and could be further evaluated in patients with relapsed or refractory multiple myeloma. FUNDING: Biotest AG.

KarMMa-RW: comparison of idecabtagene vicleucel with real-world outcomes in relapsed and refractory multiple myeloma.

Patients with relapsed and refractory multiple myeloma (RRMM) who are triple-class exposed (to an immunomodulatory agent, proteasome inhibitor, and anti-CD38 antibody) have limited treatment options and there is no standard of care. Idecabtagene vicleucel (ide-cel, bb2121), a BCMA-directed CAR T-cell therapy, demonstrated efficacy in triple-class exposed RRMM patients in the KarMMa trial (NCT03361748). In this retrospective study (KarMMa-RW), patient-level data from triple-class exposed RRMM patients were merged into a single data model and compared with KarMMa using trimmed stabilized inverse probability of treatment weighting. Endpoints included overall response rate (ORR; primary), rate of very good partial response or better (≥VGPR), progression-free survival (PFS), and overall survival (OS). Of 1949 real-world triple-class exposed RRMM patients, 190 received subsequent (index) line of therapy and met KarMMa eligibility criteria (Eligible RRMM cohort). With a median follow-up of 13.3 months in KarMMa and 10.2 months in Eligible RRMM, ORR, and ≥VGPR were significantly improved in KarMMa versus Eligible RRMM (ORR, 76.4% vs 32.2%; ≥VGPR, 57.9% vs 13.7%; both P < 0.0001) as were PFS (11.6 vs 3.5 months; P = 0.0004) and OS (20.2 vs 14.7 months; P = 0.0006). This study demonstrated that ide-cel significantly improved responses and survival compared with currently available therapies in triple-class exposed RRMM.

Phase 1b trial of isatuximab, an anti-CD38 monoclonal antibody, in combination with carfilzomib as treatment of relapsed/refractory multiple myeloma.

BACKGROUND: Isatuximab (Isa), an anti-CD38 monoclonal antibody, and carfilzomib (K), a next-generation proteasome inhibitor (PI), both have potent single-agent activity in relapsed and refractory multiple myeloma (RRMM). METHODS: This phase 1b study evaluated the combination of Isa and K in 33 patients with RRMM. Isa was administered by intravenous infusion in 3 dosing cohorts: dose level 1 (Isa at 10 mg/kg biweekly), dose level 2 (DL2; Isa at 10 mg/kg weekly for 4 doses and then biweekly), and dose level 3 (Isa at 20 mg/kg weekly for 4 doses and then biweekly) and all patients received K (20 mg/m2 intravenously for cycle 1, days 1 and 2, and then 27 mg/m2 for all subsequent doses). A standard 3+3 dose-escalation design was used, no dose-limiting toxicity was observed, and the maximum tolerated dose was not reached. An expansion cohort of 18 patients was enrolled at DL2 to further evaluate safety and efficacy. Responses were assessed with the International Myeloma Working Group response criteria, and patients continued treatment until disease progression or unacceptable toxicity. RESULTS: With a median follow-up of 26.7 months, in this heavily pretreated population with a median of 3 prior lines (refractory to PIs and immunomodulatory drugs, 76%; refractory to K, 27%), the overall response rate was 70% (stringent complete response/complete response, 4; very good partial response, 8; partial response, 11). The median progression-free survival was 10.1 months, and the 2-year survival probability was 76%. The most common treatment-related adverse events (grade 2 or higher) were anemia, leukopenia, neutropenia, thrombocytopenia, hypertension, and infection. Infusion reactions were common (55%) but did not limit dosing. CONCLUSIONS: Treatment with Isa plus K was well tolerated with no unexpected toxicity. The combination was effective despite the enrollment of heavily pretreated patients with RRMM. LAY SUMMARY: This phase 1b study was designed to assess the safety, pharmacokinetics, and preliminary efficacy of isatuximab and carfilzomib in patients with relapsed and refractory multiple myeloma. Thirty-three patients were treated: 15 in dose escalation and 18 in dose expansion. Patients received an average of 10 cycles. The treatment was safe and effective. No unexpected toxicity or drug-drug interactions were noted. Seventy percent of the subjects responded to therapy, and the progression-free survival was 10.1 months.

Associations Between Amplification (1q) and Prior Cancer in a Real-World De Novo Myeloma Cohort.

Genomic biomarkers inform treatment in multiple myeloma (MM), making patient clinical data a potential window into MM biology. We evaluated de novo MM patients for associations between specific MM cytogenetic patterns and prior cancer history. Analyzing a MM real-world dataset, we identified a cohort of 1769 patients with fluorescent in situ hybridization cytogenetic testing at diagnosis. Of the patients, 241 (0.14) had histories of prior cancer(s). Amplification of the long arm of chromosome 1 [amp(1q)] varied by prior cancer history (0.31 with prior cancer vs 0.24 without; 2-sided P = .02). No other MM translocations, amplifications, or deletions were associated with prior cancers. Amp(1q) and cancer history remained strongly associated in a logistic regression adjusting for patient demographic and disease attributes. The results merit follow-up regarding carcinogenic treatment effects and screening strategies for second malignancies. Broadly, the findings suggest that analyses of patient-level phenotypic-genomic real-world dataset may accelerate cancer research through hypothesis-generating studies.

Patient-reported outcomes following autologous stem cell transplant for patients with multiple myeloma.

We evaluated changes in patient-reported outcomes and cognitive function from pre- to 3-6 months post-treatment among 42 newly diagnosed patients with multiple myeloma undergoing transplant with complete data using PROMIS-29. There were statistically significant improvements in physical (p < .001) and mental health (p < .001) but not cognition from pre-treatment to 3-6 month follow-up. Similar results were seen within age or comorbidity strata. Patients with myeloma undergoing transplant experienced generally improved short-term health outcomes with no significant declines in cognition.

Prevalence and Survival Impact of Self-Reported Symptom and Psychological Distress Among Patients With Multiple Myeloma.

BACKGROUND: Advances in the management of multiple myeloma (MM) have extended survival and reduced painful skeletal-related events. As MM is evolving toward a chronic disease, we sought to determine the prevalence of self-reported symptom burden and psychological distress, and to determine the association of distress with survival. METHODS: The CPASS-7 patient-reported outcome instrument was administered to a convenience sample of MM patients at 7 outpatient cancer centers. RESULTS: A total of 239 patients completed the CPASS-7 between September 2015 and October 2016%; 57% of respondents were male, and median age was 67 years. Forty-eight percent were concerned that they could not do the things they wanted to do, with 33% reporting decreased performance status. Financial toxicity concerns were self-reported by 44%, with family burdens noted in 24%. Although depression was reported by only 15%, 41% noted lack of pleasure. Pain was a concern in 36%. With a median follow-up of 316 days since CPASS-7 completion, 13% of patients had died. A high total distress score was noted in 57 (24%) and trended toward an association with a decreased survival rate compared to the 182 patients (76%) with a low total distress score (P = .066). The 6-month survival rates for patients with high and low distress scores were 86% and 96%, respectively, and 12-month survival rates were 76% and 87%, respectively. CONCLUSION: Despite dramatic improvements in survival among patients with MM, symptom, financial, and psychosocial concerns continue to be major patient concerns. As MM becomes a chronic disease, additional attention to addressing these issues is required.

A phase 1b study of once-weekly carfilzomib combined with lenalidomide and dexamethasone in patients with newly diagnosed multiple myeloma.

Twice-weekly carfilzomib with lenalidomide-dexamethasone (Rd) is an effective regimen for newly diagnosed multiple myeloma (NDMM). Here we evaluated once-weekly carfilzomib with Rd (once-weekly KRd) in NDMM patients. The NDMM patients were enrolled regardless of transplant eligibility. Patients received carfilzomib on days 1, 8, and 15; lenalidomide 25 mg on days 1-21; and dexamethasone 40 mg on carfilzomib days (also day 22 for cycles 1-8) for ≤18, 28-day cycles. Enrollment initiated in a carfilzomib 20/70 mg/m2 (20 mg/m2 on cycle one, day 1; 70 mg/m2 thereafter) NDMM dose-expansion arm, which was suspended because of serious adverse events. After evaluation of dose-limiting toxicities in a two-step-up dose-evaluation cohort, an NDMM dose-expansion arm (carfilzomib 20/56 mg/m2 ) was opened. Fifty-one NDMM patients were enrolled in dose-finding and dose-expansion cohorts. Results are presented for the carfilzomib 56 mg/m2 NDMM dose-expansion arm (n = 33). The grade ≥ 3 treatment-emergent AE (TEAE) rate was 63.6%. Twenty-five patients underwent stem cell collection; 18 proceeded to auto stem cell transplant, and five resumed KRd on study after autoSCT. The overall response rate (ORR) based on best overall response by cycle four was 97.0% (≥very good partial response [VGPR], 69.7%) in the NDMM 20/56 mg/m2 cohort. In patients who did not receive autoSCT (n = 15), the median number of cycles was 16.0; ORR was 93.3% (≥VGPR, 80.0%). At a median follow-up of 8.1 months, median progression-free survival was not reached. Once-weekly KRd (carfilzomib 56 mg/m2 ) had a favorable safety profile and promising activity in NDMM, supporting the use of this regimen in this setting.

Immunomodulation in Pomalidomide, Dexamethasone, and Daratumumab-Treated Patients with Relapsed/Refractory Multiple Myeloma.

PURPOSE: Addition of daratumumab to pomalidomide and low-dose dexamethasone (LoDEX) is a safe and effective combination for relapsed/refractory multiple myeloma treatment. We sought to better understand immune combinational benefit of pomalidomide and daratumumab with LoDEX. PATIENTS AND METHODS: Immunophenotypic changes were analyzed in peripheral blood from longitudinal sampling of patients treated with this triplet regimen from cohort B of the CC4047-MM-014 phase II trial (NCT01946477). RESULTS: Consistent with the daratumumab mechanism, treatment led to decreased natural killer (NK) and B cells. In contrast, pronounced increases occurred in activated and proliferating NK and T cells, appreciably in CD8+ T cells, along with reduction in naïve and expansion of effector memory compartments. Timing of T-cell changes correlated with pomalidomide dosing schedule. Enhanced activation/differentiation did not result in increased exhausted T-cell phenotypes or increases in regulatory T cells. Similar immune enhancements were also observed in patients previously refractory to lenalidomide. CONCLUSIONS: These data support a potential mechanism for enhanced immune-mediated cytotoxicity in which daratumumab-mediated NK-cell diminution is partially offset by pomalidomide effects on the remaining NK-cell pool. Furthermore, daratumumab antimyeloma activity and elimination of CD38+ T cells (regulatory/activated) provide a rationale for therapeutic combination with direct tumoricidal activity and immunomodulation of pomalidomide-directed T-cell enhancements. These data highlight enhancements in immune subpopulations for the combination of daratumumab with pomalidomide and potentially with next-generation cereblon-targeting agents.

Pomalidomide, dexamethasone, and daratumumab in relapsed refractory multiple myeloma after lenalidomide treatment.

Patients with multiple myeloma who have relapsed after or become refractory to lenalidomide in early treatment lines represent a clinically important population in need of effective therapies. The safety and efficacy of pomalidomide, low-dose dexamethasone, and daratumumab was evaluated in lenalidomide-pretreated patients with relapsed or refractory multiple myeloma (RRMM) after one to two prior treatment lines in the phase 2 MM-014 study. Patients received pomalidomide 4 mg daily from days 1-21 and dexamethasone 40 mg weekly (28-day cycles). Daratumumab 16 mg/kg was administered per label. Primary endpoint was overall response rate (ORR); secondary endpoints included progression-free survival (PFS) and safety. Per protocol, all patients (N = 112) had received lenalidomide in their most recent prior regimen (75.0% lenalidomide refractory). ORR was 77.7% (76.2% in lenalidomide-refractory patients); median follow-up was 17.2 months. Median PFS was not reached (1-year PFS rate 75.1%). The most common hematologic grade 3/4 treatment-emergent adverse event was neutropenia (62.5%). Grade 3/4 infections were reported in 31.3% of patients, including 13.4% with grade 3/4 pneumonia. These results demonstrate the safety and efficacy of pomalidomide-based therapy as early as second line in patients with RRMM, even immediately after lenalidomide failure, indicating that switching from the immunomodulatory agent class is not necessary.