Antigen escape as a shared mechanism of resistance to BCMA-directed therapies in multiple myeloma

B-cell maturation antigen (BCMA)-targeting therapeutics have dramatically improved outcomes in relapsed/refractory multiple myeloma (RRMM). However, whether the mechanisms of resistance between these therapies are shared and how the identification of such mechanisms before therapy initiation could refine clinical decision-making remains undefined. We analyzed outcomes for 72 RRMM patients treated with teclistamab, a CD3 x BCMA bispecific antibody (BsAb), 42% (30/72) of whom had prior BCMA-directed therapy exposure. Malignant plasma cell BCMA expression was present in all BCMA therapy-naïve patients. Prior therapy-mediated loss of plasma cell BCMA expression before teclistamab treatment, measured by immunohistochemistry, was observed in 3 patients, none of whom responded to teclistamab, and one of whom also did not respond to ciltacabtagene autoleucel. Whole exome sequencing of tumor DNA from one patient revealed biallelic loss of TNFRSF17 following treatment with belantamab mafodotin. Low-to-undetectable peripheral blood soluble BCMA levels correlated with the absence of BCMA expression by bone marrow plasma cells. Thus, although rare, loss of BCMA expression following TNFRSF17 gene deletions can occur following any BCMA-directed therapy and prevents response to subsequent anti-BCMA-directed treatments, underscoring the importance of verifying the presence of a target antigen.

Unscheduled healthcare interactions in multiple myeloma patients receiving T cell redirection therapies

Outcomes for relapsed/refractory multiple myeloma (RRMM) patients have dramatically improved following the development and now growing utilization of B cell maturation antigen targeted chimeric antigen receptor (CAR) T cell therapy and bispecific antibody (BsAb) therapy. However, healthcare utilization as a quality-of-life metric in these growing populations has not been thoroughly evaluated. We performed a retrospective cohort study evaluating the frequency and cause of unscheduled healthcare interactions (UHIs) among RRMM patients responding to B-cell maturation antigen targeted BsAbs and CAR T cell therapies (N = 46). This included analysis of remote UHIs including calls to physicians' offices and messages sent through an online patient portal. Our results showed that nearly all (89%) RRMM patients receiving these therapies required a UHI during the first 125 days of treatment, with a mean of 3.7 UHIs per patient. RRMM patients responding to BsAbs were significantly more likely to remotely contact their physicians' offices (1.8-fold increase, p = 0.038) or visit an urgent care center (>3-fold increase, p = 0.012) than RRMM patients responding to CAR T cell therapies. This was largely due to increased reports of mild upper respiratory tract infections in BsAb patients. Our results underscore the need to develop preemptive management strategies for commonly reported symptoms that RRMM patients experience while receiving CAR T cell or BsAb therapies. This preemptive management may significantly reduce unnecessary healthcare utilization in this vulnerable patient population.

Patterns of CRS with Teclistamab in Relapsed/Refractory Multiple Myeloma patients with Prior T-Cell Redirection Therapy

Teclistamab (Tec) is a first-in-class BCMA X CD3 bispecific T-cell engager antibody approved for treating multiple myeloma progressing after at least 4 lines of therapy. The objective of this study was to evaluate the rate of cytokine release syndrome (CRS) in patients who were treated with commercial Tec and had prior exposure to other T-cell redirection therapies. A retrospective chart review was performed to identify patients who completed the Tec step-up dosing phase between November 2022 and November 2023. Patients were divided into 2 cohorts based on prior exposure to T-cell redirection therapy (cohort 1: T-cell redirection therapy experienced; cohort 2: T-cell redirection therapy naïve). The primary objective was to compare the differences in the rates of CRS between the two cohorts. Univariate and multivariate logistic regression analyses were performed to assess the association between CRS rates with Tec and prior treatment with T-cell redirection therapy. A total of 72 patients were included in the analysis (27 in cohort 1 and 45 in cohort 2). The CRS rates were significantly lower in cohort 1 (37%, n=10) compared to cohort 2 (80%, n=36; p=0.0004). Based on multivariate logistic regression analysis, patients without prior exposure to T-cell redirection therapy (cohort 2) had about a 4-fold increase in the incidence of CRS (95% CI: 1.40-14.90, p=0.0002) with Tec. In our study, prior exposure to T-cell redirection therapy reduced the risk of CRS with Tec during the step-up dosing phase. This observation will allow for the optimization of CRS prophylactic strategies for Tec.

CD8 effector T cells enhance teclistamab response in BCMA-exposed and -naïve multiple myeloma

ABSTRACT

Teclistamab, a B-cell maturation antigen (BCMA)- and CD3-targeting bispecific antibody, is an effective novel treatment for relapsed/refractory multiple myeloma (R/RMM), but efficacy in patients exposed to BCMA-directed therapies and mechanisms of resistance have yet to be fully delineated. We conducted a real-world retrospective study of commercial teclistamab, capturing both clinical outcomes and immune correlates of treatment response in a cohort of patients (n = 52) with advanced R/RMM. Teclistamab was highly effective with an overall response rate (ORR) of 64%, including an ORR of 50% for patients with prior anti-BCMA therapy. Pretreatment plasma cell BCMA expression levels had no bearing on response. However, comprehensive pretreatment immune profiling identified that effector CD8+ T-cell populations were associated with response to therapy and a regulatory T-cell population associated with nonresponse, indicating a contribution of immune status in outcomes with potential utility as a biomarker signature to guide patient management.

Outcomes and Management of the SARS-CoV2 Omicron Variant in Recipients of Hematopoietic Cell Transplantation and Chimeric Antigen Receptor T Cell Therapy

Hematopoietic cell transplantation (HCT) and chimeric antigen receptor T cell therapy (CAR-T) recipients who develop Coronavirus disease 2019 (COVID-19) can have decreased overall survival (OS), likely due to disease-inherent and therapy-related immunodeficiency. The availability of COVID-19-directed therapies and vaccines have improved COVID-19-related outcomes, but immunocompromised individuals remain vulnerable. Specifically, the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant infections, including Omicron and its sublineages, particularly in HCT recipients, remain to be defined. The aim of this study was to compare the impact of SARS-CoV-2 Omicron infections in HCT/CAR-T recipients with outcomes previously reported for ancestral SARS-CoV-2 infections early in the pandemic (March to June 2020). This was a retrospective analysis of adult HCT/CAR-T recipients diagnosed with COVID-19 at Memorial Sloan Kettering Cancer Center between July 2021 and July 2022. We identified 353 patients (172 autologous HCT recipients [49%], 152 allogeneic HCT recipients [43%], and 29 CAR-T recipients [8%]), with a median time from HCT/CAR-T to SARS-CoV-2 infection of 1010 days (interquartile range, 300 to 2046 days). Forty-one patients (12%) were diagnosed with COVID-19 during the delta wave, and 312 patients (88%) were diagnosed during the Omicron wave. Risk factors associated with increased odds of COVID-19-related hospitalization were the presence of 2 or more comorbidities (odds ratio [OR], 4.9; 95% confidence interval [CI], 2.4 to 10.7; P < .001), CAR-T therapy compared to allogeneic HCT (OR, 7.7; 95% CI, 3.0 to 20.0; P < .001), hypogammaglobulinemia (OR, 2.71; 95% CI, 1.06 to 6.40; P = .027), and age at COVID-19 diagnosis (OR, 1.03; 95% CI, 1.0 to 1.05; P = .04). In contrast, infection during the Omicron variant BA5/BA4-dominant period compared to variant BA1 (OR, .21; 95% CI, .03 to .73; P = .037) and more than 3 years from HCT/CAR-T therapy to COVID-19 diagnosis compared to early infection at <100 days (OR, .31; 95% CI, .12 to .79; P = .011) were associated with a decreased odds for hospitalization. The OS at 12 months from COVID-19 diagnosis was 89% (95% CI, 84% to 94%), with 6 of 26 deaths attributable to COVID-19. Patients with the ancestral strain of SAR-CoV-2 had a lower OS at 12 months, with 73% (95% CI, 62% to 84%) versus 89% (95% CI, 84% to 94%; P < .001) in the Omicron cohort. Specific COVID-19 treatment was administered in 62% of patients, and 84% were vaccinated with mRNA COVID-19 vaccines. Vaccinated patients had significantly better OS than unvaccinated patients (90% [95% CI, 86% to 95%] versus 82% [95% CI, 72% to 94%] at 12 months; P = .003). No significant difference in OS was observed in patients infected with the Omicron and those infected with the Delta variant (P = .4) or treated with specific COVID-19 treatments compared with those not treated (P = .2). We observed higher OS in HCT and CAR-T recipients infected with the Omicron variants compared to those infected with the ancestral strain of SARS-CoV2. The use of COVID-19 antivirals, mAbs, and vaccines might have contributed to the improved outcomes.

Randomized Phase II Trial of Dendritic Cell/Myeloma Fusion Vaccine with Lenalidomide Maintenance after Upfront Autologous Hematopoietic Cell Transplantation for Multiple Myeloma: BMT CTN 1401

PURPOSE

Vaccination with dendritic cell (DC)/multiple myeloma (MM) fusions has been shown to induce the expansion of circulating multiple myeloma-reactive lymphocytes and consolidation of clinical response following autologous hematopoietic cell transplant (auto-HCT).

PATIENTS AND METHODS

In this randomized phase II trial (NCT02728102), we assessed the effect of DC/MM fusion vaccination, GM-CSF, and lenalidomide maintenance as compared with control arms of GM-CSF and lenalidomide or lenalidomide maintenance alone on clinical response rates and induction of multiple myeloma-specific immunity at 1-year posttransplant.

RESULTS

The study enrolled 203 patients, with 140 randomized posttransplantation. Vaccine production was successful in 63 of 68 patients. At 1 year, rates of CR were 52.9% (vaccine) and 50% (control; P = 0.37, 80% CI 44.5%, 61.3%, and 41.6%, 58.4%, respectively), and rates of VGPR or better were 85.3% (vaccine) and 77.8% (control; P = 0.2). Conversion to CR at 1 year was 34.8% (vaccine) and 27.3% (control; P = 0.4). Vaccination induced a statistically significant expansion of multiple myeloma-reactive T cells at 1 year compared with before vaccination (P = 0.024) and in contrast to the nonvaccine arm (P = 0.026). Single-cell transcriptomics revealed clonotypic expansion of activated CD8 cells and shared dominant clonotypes between patients at 1-year posttransplant.

CONCLUSIONS

DC/MM fusion vaccination with lenalidomide did not result in a statistically significant increase in CR rates at 1 year posttransplant but was associated with a significant increase in circulating multiple myeloma-reactive lymphocytes indicative of tumor-specific immunity. Site-specific production of a personalized cell therapy with centralized product characterization was effectively accomplished in the context of a multicenter cooperative group study. See related commentary by Qazilbash and Kwak, p. 4703.

Genomic and immune signatures predict clinical outcome in newly diagnosed multiple myeloma treated with immunotherapy regimens

Despite improving outcomes, 40% of patients with newly diagnosed multiple myeloma treated with regimens containing daratumumab, a CD38-targeted monoclonal antibody, progress prematurely. By integrating tumor whole-genome and microenvironment single-cell RNA sequencing from upfront phase 2 trials using carfilzomib, lenalidomide and dexamethasone with daratumumab ( NCT03290950 ), we show how distinct genomic drivers including high APOBEC mutational activity, IKZF3 and RPL5 deletions and 8q gain affect clinical outcomes. Furthermore, evaluation of paired bone marrow profiles, taken before and after eight cycles of carfilzomib, lenalidomide and dexamethasone with daratumumab, shows that numbers of natural killer cells before treatment, high T cell receptor diversity before treatment, the disappearance of sustained immune activation (that is, B cells and T cells) and monocyte expansion over time are all predictive of sustained minimal residual disease negativity. Overall, this study provides strong evidence of a complex interplay between tumor cells and the immune microenvironment that is predictive of clinical outcome and depth of treatment response in patients with newly diagnosed multiple myeloma treated with highly effective combinations containing anti-CD38 antibodies.

The Simplified Comorbidity Index predicts non-relapse mortality in reduced-intensity conditioning allogeneic haematopoietic cell transplantation

Comorbidity assessment before allogeneic haematopoietic cell transplantation (allo-HCT) is essential for estimating non-relapse mortality (NRM) risk. We previously developed the Simplified Comorbidity Index (SCI), which captures a small number of 'high-yield' comorbidities and older age. The SCI was predictive of NRM in myeloablative CD34-selected allo-HCT. Here, we evaluated the SCI in a single-centre cohort of 327 patients receiving reduced-intensity conditioning followed by unmanipulated allografts from HLA-matched donors. Among the SCI factors, age above 60, mild renal impairment, moderate pulmonary disease and cardiac disease were most frequent. SCI scores ranged from 0 to 8, with 39%, 20%, 20% and 21% having scores of 0-1, 2, 3 and ≥4 respectively. Corresponding cumulative incidences of 3-year NRM were 11%, 16%, 22% and 27%; p = 0.03. In multivariable models, higher SCI scores were associated with incremental risks of all-cause mortality and NRM. The SCI had an area under the receiver operating characteristic curve of 65.9%, 64.1% and 62.9% for predicting 1-, 2- and 3-year NRM versus 58.4%, 60.4% and 59.3% with the haematopoietic cell transplantation comorbidity index. These results demonstrate for the first time that the SCI is predictive of NRM in patients receiving allo-HCT from HLA-matched donors after reduced-intensity conditioning.

Bortezomib, lenalidomide and dexamethasone (VRd) vs carfilzomib, lenalidomide and dexamethasone (KRd) as induction therapy in newly diagnosed multiple myeloma

Lenalidomide and dexamethasone with bortezomib (VRd) or carfilzomib (KRd) are commonly used induction regimens in the U.S. This single-center, retrospective study evaluated outcomes and safety of VRd and KRd. Primary endpoint was progression-free survival (PFS). Of 389 patients with newly diagnosed multiple myeloma, 198 received VRd and 191 received KRd. Median PFS was not reached (NR) in both groups; 5-year PFS was 56% (95%CI, 48-64%) for VRd and 67% (60-75%) for KRd (P = 0.027). Estimated 5-year EFS was 34% (95%CI, 27-42%) for VRd and 52% (45-60%) for KRd (P < 0.001) with corresponding 5-year OS of 80% (95%CI, 75-87%) and 90% (85-95%), respectively (P = 0.053). For standard-risk patients, 5-year PFS was 68% (95%CI, 60-78%) for VRd and 75% (65-85%) for KRd (P = 0.20) with 5-year OS of 87% (95%CI, 81-94%) and 93% (87-99%), respectively (P = 0.13). For high-risk patients, median PFS was 41 months (95%CI, 32.8-61.1) for VRd and 70.9 months (58.2-NR) for KRd (P = 0.016). Respective 5-year PFS and OS were 35% (95%CI, 24-51%) and 69% (58-82%) for VRd and 58% (47-71%) and 88% (80-97%, P = 0.044) for KRd. Overall, KRd resulted in improved PFS and EFS with a trend toward improved OS compared to VRd with associations primarily driven by improvements in outcome for high-risk patients.

Tracking the evolution of therapy-related myeloid neoplasms using chemotherapy signatures

Patients treated with cytotoxic therapies, including autologous stem cell transplantation, are at risk for developing therapy-related myeloid neoplasms (tMN). Preleukemic clones (ie, clonal hematopoiesis [CH]) are detectable years before the development of these aggressive malignancies, although the genomic events leading to transformation and expansion are not well defined. Here, by leveraging distinctive chemotherapy-associated mutational signatures from whole-genome sequencing data and targeted sequencing of prechemotherapy samples, we reconstructed the evolutionary life-history of 39 therapy-related myeloid malignancies. A dichotomy was revealed, in which neoplasms with evidence of chemotherapy-induced mutagenesis from platinum and melphalan were hypermutated and enriched for complex structural variants (ie, chromothripsis), whereas neoplasms with nonmutagenic chemotherapy exposures were genomically similar to de novo acute myeloid leukemia. Using chemotherapy-associated mutational signatures as temporal barcodes linked to discrete clinical exposure in each patient's life, we estimated that several complex events and genomic drivers were acquired after chemotherapy was administered. For patients with prior multiple myeloma who were treated with high-dose melphalan and autologous stem cell transplantation, we demonstrate that tMN can develop from either a reinfused CH clone that escapes melphalan exposure and is selected after reinfusion, or from TP53-mutant CH that survives direct myeloablative conditioning and acquires melphalan-induced DNA damage. Overall, we revealed a novel mode of tMN progression that is not reliant on direct mutagenesis or even exposure to chemotherapy. Conversely, for tMN that evolve under the influence of chemotherapy-induced mutagenesis, distinct chemotherapies not only select preexisting CH but also promote the acquisition of recurrent genomic drivers.

Abstract 6785: Dendritic cell/myeloma fusion vaccine with lenalidomide maintenance following autologous hematopoietic cell transplant induced T cell activation and expansion

Introduction: Multiple myeloma (MM), a clonal disorder of terminally differentiated plasma cells, is the second most common hematologic malignancy with ~57.9% 5-year survival rate. Current MM therapies are not curative and in most patients MM relapse. Aiming to restore antitumor immunity and counteract MM evolution, we have developed a personalized dendritic(DC)/MM cell fusion vaccine, whereby several tumor antigens are presented in the context of DC mediated co-stimulation. BMT CTN 1401 is a multicenter randomized phase II clinical trial (NCT02728102) evaluating the efficacy of the DC/MM vaccine combined with lenalidomide maintenance (Len) after autoHCT. 203 patients were enrolled from 18 centers. Aim: To evaluate the impact of the DC/MM vaccine on the establishment of anti-MM immune response we profiled the peripheral blood (PB) immune landscape at the single-cell level, with particular focus on the T cell compartment.

Method: We performed single-cell immunoprofiling (gene expression + V(D)J sequencing) on 40 patients (3xDC/MM vaccine/Len/GM-CSF: N=20; Len/GM-CSF: N=10; Len: N=10). 160 PB mononuclear cells (PBMC) samples were collected at enrollment, prior to Len, after 1 and 3 vaccines and were processed using the 10x Genomics single cell 5' assay. Here we present the analysis relative to 52 PBMC samples from 13 vaccinated patients included in the initial study cohort. The remaining 108 PBMC samples have already been subjected to single-cell immunoprofiling and the analysis is ongoing.

Results: 309,423 cells passed quality-check identifying 47 cell populations, corresponding to 20 major compartments. The T cell compartment (146,373 cells) was divided into 14 different cell populations including activated CD8, CD4, and NKT cells that exhibited a gradual increase during the course of the study. Relatively, TCR sequencing demonstrated a recovery of T cell clonal diversity and a progressive rise in the frequency of expanded clonotypes within the activated CD4 and cytotoxic T cell populations after vaccination. Consistently, we observed a progressively raised number of shared TCR clonotypes within the activated CD8 and CD4 T cell subsets. The identification of common epitope/paratope hotspots among the expanded clonotypes and the different patients revealed a higher proportion of shared TCR clonotype groups across patients after vaccination compared to the early post-transplant period, predominantly after 3 vaccinations.

Conclusions: Assessment of PBMC samples from 13 vaccinated patients provided a detailed picture of the PBMC landscape. The constant T cell expansion in patients following vaccination coupled with the shared paratope/epitope hotspots and TCR signatures among patients indicated the TCR cross-reactivity and suggested for the establishment of an anti-MM immune response.

Citation Format: Giulia Cheloni, Dimitra Karagkouni, Daniela Torres, David J. Chung, Nina Shah, Natalie S. Callander, Thinle Chodon, Yvonne Efebera, Nancy Geller, Peiman Hematti, Hillard Lazarus, Ehsan Malek, Philip L. McCarthy, Ajay K. Nooka, Jacalyn Rosenblatt, Aaron P. Rapoport, Robert J. Soiffer, Dina Stroopinsky, Edmund K. Waller, Marcelo C. Pasquini, Ioannis Vlachos, David Avigan. Dendritic cell/myeloma fusion vaccine with lenalidomide maintenance following autologous hematopoietic cell transplant induced T cell activation and expansion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6785.

Association of patient activity bio-profiles with health-related quality of life in patients with newly diagnosed multiple myeloma: a prospective observational cohort study

BACKGROUND

Due to the nature of their disease, patients with multiple myeloma (MM) often have bone disease-related pain that limits physical activity and diminishes health-related quality of life (HRQOL). Digital health technology with wearables and electronic patient reported outcome (ePRO) tools can provide insights into MM HRQoL.

METHODS

In this prospective observational cohort study conducted at Memorial Sloan Kettering Cancer in NY, NY, USA, patients with newly diagnosed MM (n = 40) in two cohorts (Cohort A - patients <65 years; Cohort B - patients ≥65 years) were passively remote-monitored for physical activity at baseline and continuously for up to 6 cycles of induction therapy from Feb 20, 2017 to Sep 10, 2019. The primary endpoint of the study was to determine feasibility of continuous data capture, defined as 13 or more patients of each 20-patient cohort compliant with capturing data for ≥16 h of a 24-hr period in ≥60% of days of ≥4 induction cycles. Secondary aims explored activity trends with treatment and association to ePRO outcomes. Patients completed ePRO surveys (EORTC - QLQC30 and MY20) at baseline and after each cycle. Associations between physical activity measurements, QLQC30 and MY20 scores, and time from the start of treatment were estimated using a linear mixed model with a random intercept.

FINDINGS

Forty patients were enrolled onto study, and activity bioprofiles were compiled among 24/40 (60%) wearable user participants (wearing the device for at least one cycle). In an intention to treat feasibility analysis, 21/40 (53%) patients [12/20 (60%) Cohort A; 9/20 (45%) Cohort B] had continuous data capture. Among data captured, overall activity trended upward cycle over cycle for the entire study cohort (+179 steps/24 h per cycle; p = 0.0014, 95% CI: 68-289). Older patients (age ≥65 years) had higher increases in activity (+260 steps/24 h per cycle; p < 0.0001, 95% CI: -154 to 366) compared to younger patients (+116 steps/24 h per cycle; p = 0.21, 95% CI: -60 to 293). Activity trends associated with improvement of ePRO domains, including physical functioning scores (p < 0.0001), global health scores (p = 0.02), and declining disease burden symptom scores (p = 0.042).

INTERPRETATION

Our study demonstrates that feasibility of passive wearable monitoring is challenging in a newly diagnosed MM patient population due to patient use. However, overall continuous data capture monitoring remains high among willing user participants. As therapy is initiated, we show improving activity trends, mainly in older patients, and that activity bioprofiles correlate with traditional HRQOL measurements.

FUNDING

Grants -National Institutes of HealthP30 CA 008748, Awards - Kroll Award 2019.

Assessment of renal outcome following therapy in monoclonal immunoglobulin deposition disease: Emphasizing the need for a consensus approach

Monoclonal immunoglobulin deposition disease (MIDD), often associated with plasma cell dyscrasias, predominantly affects the kidneys. In this disease, hematologic response (HR) to treatment can be reliably assessed by International Myeloma Working Group (IMWG) consensus criteria, while uniform criteria for assessing renal response are lacking. We report a retrospective analysis of renal outcomes among 34 patients with MIDD. With most patients treated with bortezomib and autologous stem cell transplantation, 26 of 28 (94%) achieved very good partial HR or better. We demonstrate that both IMWG (based on estimated glomerular filtration rate, eGFR) and amyloid (based on proteinuria) criteria are needed to capture renal response: among 28 evaluable patients, 6 (21%) had isolated proteinuria, while 13 (46%) had isolated decreased eGFR. Using both criteria, which were concordant in patients with both decreased eGFR and proteinuria, 22 of 28 patients (79%) achieved a renal response, including 2 of 7 discontinuing dialyses. All 6 patients (100%) with isolated proteinuria and 7 of 13 (54%) with isolated decreased eGFR achieved renal response, suggesting that isolated proteinuria is an early manifestation of MIDD associated with reversible renal damage. Baseline eGFR predicted renal response (p = .02 by quartile) and survival (p = .02), while HR (CR vs. non-CR) did not, probably because of high HR rate. With a median follow-up of 110 months, the median overall survival was 136 months (95% CI: 79-NR) and median renal survival had not been reached. Prospective studies using uniform renal response criteria are needed to optimize the management of MIDD.

Sustained Minimal Residual Disease Negativity in Multiple Myeloma is Associated with Stool Butyrate and Healthier Plant-Based Diets

PURPOSE

Sustained minimal residual disease (MRD) negativity is associated with long-term survival in multiple myeloma. The gut microbiome is affected by diet, and in turn can modulate host immunity, for example through production of short-chain fatty acids including butyrate. We hypothesized that dietary factors affect the microbiome (abundance of butyrate-producing bacteria or stool butyrate concentration) and may be associated with multiple myeloma outcomes.

EXPERIMENTAL DESIGN

We examined the relationship of dietary factors (via a food frequency questionnaire), stool metabolites (via gas chromatography-mass spectrometry), and the stool microbiome (via 16S sequencing - α-diversity and relative abundance of butyrate-producing bacteria) with sustained MRD negativity (via flow cytometry at two timepoints 1 year apart) in myeloma patients on lenalidomide maintenance. The Healthy Eating Index 2015 score and flavonoid nutrient values were calculated from the food frequency questionnaire. The Wilcoxon rank sum test was used to evaluate associations with two-sided P < 0.05 considered significant.

RESULTS

At 3 months, higher stool butyrate concentration (P = 0.037), butyrate producers (P = 0.025), and α-diversity (P = 0.0035) were associated with sustained MRD negativity. Healthier dietary proteins, (from seafood and plants), correlated with butyrate at 3 months (P = 0.009) and sustained MRD negativity (P = 0.05). Consumption of dietary flavonoids, plant nutrients with antioxidant effects, correlated with stool butyrate concentration (anthocyanidins P = 0.01, flavones P = 0.01, and flavanols P = 0.02).

CONCLUSIONS

This is the first study to demonstrate an association between a plant-based dietary pattern, stool butyrate production, and sustained MRD negativity in multiple myeloma, providing rationale to evaluate a prospective dietary intervention.

A prospective study of dysgeusia and related symptoms in patients with multiple myeloma after autologous hematopoietic cell transplantation

BACKGROUND

Dysgeusia is a common but understudied complication in patients undergoing autologous hematopoietic cell transplantation (auto-HCT). We assessed the feasibility of using chemical gustometry (CG) to measure dysgeusia and explored its associations with symptom burden, nutrition, chemotherapy pharmacokinetics (PK), and the oral microbiome.

METHODS

We conducted a single-center, prospective feasibility study (NCT03276481) of patients with multiple myeloma undergoing auto-HCT. CG was performed longitudinally testing five flavors (sweet, sour, salty, bitter, umami) to calculate a total taste score (maximum score, 30). We measured caloric intake and patient-reported symptoms, assessing their correlation with oral microbiota composition and salivary and blood melphalan PK exposure.

RESULTS

Among all 45 patients, 39 (87%) completed at least four (>60%) and 22 (49%) completed all six CG assessments. Median total CG scores remained stable over time but were lowest at day +7 (27, range 24-30) with recovery by day +100. Symptom burden was highest by day +10 (area under the curve, 2.9; range, 1.0-4.6) corresponding with the lowest median overall caloric intake (1624 kcal; range, 1345-2267). Higher serum/salivary melphalan levels correlated with higher patient-reported dysgeusia and lower caloric intake. Oral microbiota α-diversity was stable early and increased slightly by day +100.

CONCLUSIONS

Assessment of dysgeusia by CG is feasible after auto-HCT. Most dysgeusia, symptom burden, and lowest caloric intake occurred during the blood count nadir. Higher melphalan concentrations correlated with more dysgeusia and poorer caloric intake. Future studies will aim to modulate melphalan exposure by PK-targeted dosing and characterize patient taste preferences to personalize diets for improved nutritional intake.

LAY SUMMARY

Taste changes after cancer treatments are very common. We used chemical gustometry (taste testing) to study taste changes and to better understand why patients with multiple myeloma experience this symptom after autologous hematopoietic cell transplantation. We found that taste testing was feasible, taste changes peaked when blood counts were lowest, and most patients recovered their taste by 100 days after transplantation. Taste changes correlated with lower food intake and with higher levels of chemotherapy in the body. Future work will focus on using personalized chemotherapy doses to reduce taste changes and to match patients' individual taste preferences with their diets.

Continuous induction with lenalidomide/dexamethasone versus autologous stem cell transplantation in newly diagnosed multiple myeloma: a case for response-adapted approach

Although upfront autologous stem cell transplantation (ASCT) generally improves progression-free survival (PFS) in newly diagnosed multiple myeloma (NDMM), the overall survival (OS) benefit and optimal timing of ASCT are not well established. Patients with early response may be able to safely continue induction and avoid ASCT without compromised outcomes. We report an extended follow-up analysis of a phase 2 trial that randomized transplant-eligible patients with NDMM who responded to induction (50/65 patients) to continued induction or ASCT; median follow-up was 8.0 years. Patients had similar 8-year PFS (55% vs. 43%), 8-year OS (83% vs. 72%), and rates of at least very good partial response (72% vs. 84%) whether continuing induction of lenalidomide and dexamethasone (Ld arm) or receiving ASCT (Ld + ASCT arm) (p = 0.5). Notably, over 50% of patients receiving continuous Ld had PFS of 5-10 years. These results suggest the need for prospective trials incorporating response-adapted therapeutic approaches to NDMM.STATEMENT OF PRIOR PRESENTATIONPresented in abstract form (interim analysis) at the 56th annual meeting of the American Society of Hematology (San Francisco, CA, 6 December 2014) and at the 57th annual meeting of the American Society of Hematology (Orlando, FL, 3 December 2015).

Abstract 5747: Chemotherapy-related mutational signatures reveal the origins of therapy-related myeloid neoplasms

Patients treated with chemotherapy (CT) and/or autologous stem-cell transplantation (ASCT) are at risk for therapy-related myeloid neoplasms (tMN). Certain cytotoxic agents introduce mutations within distinct trinucleotide contexts resulting in a unique barcode for each exposed cell. We leveraged mutational signatures to investigate the role of CT in the genomic landscape of tMN with respect to antecedent clonal hematopoiesis (CH).

We analyzed 32 tMN and 2 tALL from 33 patients and interrogated for copy number abnormalities (CNA), structural variants (SV), single nucleotide variants (SNV), and mutational signatures. For 7 patients with tMN post-melphalan/ASCT, we investigated antecedent CH using targeted sequencing on pre-melphalan samples, including autograft products.

CH variants that became clonal in tumor were seen in 5/7 pre-melphalan/ASCT samples (TP53, RUNX1, NCOR1, NF1, CREBBP, DNMT3A, and PPM1D). Complex SV were seen in 7 tMNs; including chromothripsis in 6 (19.4%). In 4 cases, chromothripsis involved chromosome 19 with hyper-amplification of the SMARCA4 locus (≥5 copies). Mutational signature analysis revealed 6 known single base substitution (SBS) signatures in tMN including melphalan (SBS-MM1) and platinum signatures (SBS31, SBS35, and E-SBS37). TMNs with CT signatures had higher mutation burden than those without (p = 0.004). 17 patients with exposure to agents other than melphalan/platinum did not have increased mutational burden with respect to de novo AML (TCGA; NEJM, 2013).

All patients with prior platinum exposure (including tALL, n=9) had platinum SBS signatures while only 2 of 7 patients with prior melphalan/ASCT had a melphalan signature (SBS-MM1). Detection of CT signatures in bulk sequencing relies on one cell, with its barcode of mutations, to expand to clonal dominance. Given pre-existent CH, including in 3/3 autograft products, absence of a CT signature despite melphalan exposure implies progression by a clone that escaped CT exposure with stem-cell collection and reinfusion. Conversely, all platinum-exposed tAML had signature evidence of exposure confirming existence of CH prior to exposure and supporting post-CT single-cell expansion. TMNs from 3 patients exposed to sequential platinum and melphalan/ASCT had platinum but not melphalan signatures confirming single-cell expansion of the pre-tMN CH clone post-platinum but with escape from exposure to melphalan via leukapheresis. Chromothripsis events bore only non-duplicated CT-induced mutations, indicative of acquisition prior to, and not directly caused by, CT exposure.

These disparities suggest that ASCT provides a mechanism for CH clones to escape CT and re-engraft with transplant. Coupled with driver events accrued prior to CT, this suggest that CT-induced mutagenesis may be less important than other factors, such as CT-induced immunosuppression, in the expansion of pre-TMN CH clones.

Citation Format: Benjamin Diamond, Bachisio Ziccheddu, Eileen M. Boyle, Kylee Maclachlan, Justin Taylor, Justin M. Watts, Sydney X. Lu, David G. Coffey, Niccolo Bolli, Elli Papaemmanuil, Kelly Bolton, Jae H. Park, Heather Landau, Karuna Ganesh, Mikkael A. Sekeres, Stephen Nimer, David J. Chung, Caleb H. Ho, Mikhail Roshal, Alexander Lesokhin, Gareth Morgan, Ola Landgren, Francesco Maura. Chemotherapy-related mutational signatures reveal the origins of therapy-related myeloid neoplasms [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5747.

Evaluating serum-free light chain ratio as a biomarker for multiple myeloma

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Background: In 2014, the definition of multiple myeloma was updated to include serum free light chain (FLC) ratio ≥100 as a myeloma defining biomarker, based on retrospective data indicating a 2-year progression rate of 80% and a median time to progression (TTP) of 12 months associated with this marker. However, two recent studies have reported lower 2-year progression rates, 30-44%, and longer median TTP of 40 months in patients with FLC ratio ≥100. Because of the disparity in risk prediction by FLC ratio across studies, we were motivated to assess the risk of progression in patients with SMM and a FLC ratio ≥100. Methods: We performed a retrospective analysis of patients diagnosed with SMM at Memorial Sloan Kettering Cancer Center between January 2000 and December 2017. Diagnosis of SMM and progression to MM was defined according to the International Myeloma Working Group (IMWG) criteria at the time of diagnosis. Kaplan-Meier method was used to assess TTP and generate survival curves, with log-rank test for comparison between groups. Results: A total of 438 patients were included in the study, with a median follow-up time of 52 months. While all patients with a FLC ratio ≥100 (n = 66) had elevated involved FLC levels, 35 (53%) had an involved FLC concentration > 100 mg/L. Per current diagnostic criteria, we only included patients with an involved FLC concentration > 100 mg/L in the FLC ratio ≥100 group, and found a median TTP of 31 months (95% confidence interval [CI] 16-59 months) and a 2-year progression rate of 49% (CI 28-63%). In a sensitivity analysis including all 66 cases with FLC ratio ≥100 (independent of involved FLC concentration), we found the median TTP to be 41 months (CI 30-72 months), compared to 101 months for those with a FLC ratio < 100 (CI 78-127 months; p < 0.0001). The risk of progression within 2 years was 35% (CI 22-46%) compared to 18% (CI 14-23%; p < 0.0001). Of note, 22 patients with a FLC ratio ≥100 were monitored expectantly for > 4 years, among whom 12 patients had an involved FLC level > 100 mg/L. Ten patients (7 with involved FLC level > 100 mg/L) were followed over a period ranging from 4 to 8.5 years before eventually progressing, and 12 patients (5 with involved FLC level > 100 mg/L) were followed between 4 and 8 years and did not progress during the study period. Conclusions: While FLC ratio ≥100 is associated with a high risk of progression in patients with SMM, it does not infer an imminent risk of progression, defined by the IMWG as median TTP of 12 months and 2-year progression rate of at least 80%. On the contrary, select patients with FLC ratio ≥100 can be followed for many years without progressing and some may never progress despite long-term follow-up. These findings suggest that in patients where FLC ratio ≥100 is the only myeloma-defining event, other high-risk features as well as the evolution of FLCs over time should be considered in the decision to start a patient on treatment.

Clinical efficacy of daratumumab (DARA)-based second line therapy after DARA-containing and DARA-free induction therapies in multiple myeloma: A single center experience

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Background: DARA has been FDA approved for newly diagnosed multiple myeloma (NDMM) in combination with lenalidomide/dexamethasone (Rd), bortezomib/melphalan/dex, and bortezomib/thalidomide/dex since 2018. With the increase use of DARA combinations in NDMM, understanding the role of DARA retreatment at relapse needs to be examined in clinical practice. Herein, we describe a single institution experience of the efficacy of DARA-based retreatment as second line of therapy (LOT2) for patients (pts) who received DARA-based induction compared to DARA-free induction regimens. Methods: Thirty-three pts treated with DARA-based LOT2 at MSK from 1/2015 to 9/2021 were included in this retrospective analysis. Primary endpoint was overall response rate (ORR; ≥PR by IMWG criteria). Discrete patient characteristics were summarized by frequency (percentage) and continuous characteristics were summarized by median (IQR). Progression free survival (PFS) was evaluated by Kaplan-Meier method. Results: Two cohorts were identified based on prior DARA exposure: cohort 1 (N=6) received DARA-based induction without meeting DARA-refractory criteria and cohort 2 (N=27) had carfilzomib and Rd (KRd) induction (Table). Median follow-up was 13.8 and 14.5 months for cohorts 1 and 2, respectively. In cohort 1, 5 pts received DARA-KRd and 1 had DRd as first line therapy (LOT1). Median time between last dose of DARA in LOT1 and first dose of DARA in LOT2 was 17.5 months (IQR 12.1-19.8). ORR were 83% and 79% for cohorts 1 and 2, respectively. In cohort 1, ORR comprised of 1 sCR, 1 VGPR, and 3 PR. For cohort 2, there were 5 sCR/CR, 7 VGPR, and 9 PR. Median PFS was not reached in cohort 1 and 16.2 months in cohort 2. Conclusions: In a cohort of pts retreated with DARA after DARA-based induction, our findings suggest that DARA-exposed MM pts may derive benefit from DARA retreatment in subsequent lines of therapy similarly to pts who were DARA-naïve prior to DARA-based LOT2. Longer follow-up is needed to assess survival outcomes. In addition, larger confirmatory studies are warranted to further characterize response characteristics of DARA combinations in LOT2, especially as DARA-based therapy is increasingly used in treating NDMM. [Table: see text]

African American patients with smoldering multiple myeloma may have a lower risk of progression compared to White patients

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Background: The incidence of multiple myeloma (MM) is two to threefold higher in African Americans (AAs) compared to whites when adjusted for socioeconomics, age, and sex. However, there is limited information on whether racial background affects the risk of progression from smoldering MM (SMM) to MM. Methods: Patients with SMM presenting to Memorial Sloan Kettering Cancer Center between the years 2000 and 2019 and who identified as either AA or white were included in the study. Baseline characteristics were collected at the time of diagnosis including laboratory, imaging, and pathology reports. Differences in distributions of continuous and discrete characteristics were assessed by Kruskal-Wallis and chi-square tests. Time to progression (TTP) was assessed using the Kaplan-Meier method with log-rank test for comparisons. Univariate and multivariate Cox proportional hazard models were used to estimate effects of risk factors on TTP with hazard ratios (HR) and 95% confidence intervals (CI). Results: A total of 576 patients were included (70 were AA, 12%). Median follow-up time was 3 years in AAs and 4 years in whites. Differences in baseline characteristics between AAs and whites included median age (60 years in AAs vs 64 years in whites, p = 0.01), median hemoglobin level (12.3g/dL in AA vs 12.8g/dL in whites, p = 0.02), and immunoparesis including 1 or 2 uninvolved immunoglobulins (31% and 10% in AAs vs 56% and 27% in whites, p = 0.002). There was no difference in bone marrow plasma cells, M-spike, free light chain ratio, or Mayo-2018 SMM risk score. AA race was associated with a significantly decreased risk of progression in the univariate model (HR 0.57, CI 0.34-0.94). In the multivariate model adjusting for age, sex, and variables associated with an increased risk of progression in the univariate model (bone marrow plasma cells, M-spike, free light chain ratio, immunoparesis and low albumin), AA race remained associated with a decreased risk of progression (HR 0.39, CI 0.16-0.95). Overall, AA patients with SMM had a significantly (p = 0.027) longer median TTP (9.7 vs 6.2 years), and a lower 2-year (12.6% vs 20.1%) and 5-year (34% vs 44.6%) progression rate than whites. Because AA patients were younger at diagnosis, we stratified patients by age group, < 65 vs ≥65 years. In patients < 65 years, there was no difference in progression rate. In patients aged ≥65 years, AA patients continued to have a longer TTP than whites (9.8 vs 5.2 years, p = 0.02). Conclusions: In our retrospective single institution experience, AA patients with SMM had a lower risk of progression to MM compared to whites. Both groups had similar Mayo-2018 risk scores, however, AA patients had a lower degree of immunoparesis at baseline. Future studies are needed to better understand if these differences are explained by differences in disease biology including genomic mechanisms, immune microenvironment, and systemic immune response.

Capture Rate of V(D)J Sequencing for Minimal Residual Disease Detection in Multiple Myeloma

PURPOSE

Minimal residual disease (MRD) negativity is a strong predictor for outcome in multiple myeloma. To assess V(D)J clonotype capture using the updated Adaptive next-generation sequencing (NGS) MRD assay in a clinical setting, we analyzed baseline and follow-up samples from patients with multiple myeloma who achieved deep clinical responses.

EXPERIMENTAL DESIGN

A total of 159 baseline and 31 follow-up samples from patients with multiple myeloma were sequenced using the NGS MRD assay. Baseline samples were also sequenced using a targeted multiple myeloma panel (myTYPE). We estimated ORs with 95% confidence intervals (CI) for clonotypes detection using logistic regression.

RESULTS

The V(D)J clonotype capture rate was 93% in baseline samples with detectable genomic aberrations, indicating presence of tumor DNA, assessed through myTYPE. myTYPE-positive samples had significantly higher V(D)J clonotype detection rates in univariate (OR, 7.3; 95% CI, 2.8-22.6) and multivariate analysis (OR, 4.4; 95% CI, 1.4-16.9; P = 0.016). Higher disease burden was associated with higher probability of V(D)J clonotype capture, meanwhile no such association was found for age, gender, or type of heavy or light immunoglobulin chain. All V(D)J clonotypes detected at baseline were detected in MRD-positive samples indicating that the V(D)J clonotypes remained stable and did not undergo further rearrangements during follow-up. Of the 31 posttreatment samples, 12 were MRD-negative using the NGS MRD assay.

CONCLUSIONS

NGS for V(D)J rearrangements in multiple myeloma offers a reliable and sensitive method for MRD tracking with high detection rates in the clinical setting.

Hematopoietic Cell Transplantation is Feasible in Patients with Prior COVID-19 Infection

There are limited data on outcomes of patients with prior Coronavirus disease 2019 (COVID-19) who proceeded to autologous or allogeneic hematopoietic cell transplantation (HCT). Whether these patients are more susceptible to poor outcomes and recurrence of COVID-19 is unknown. We report a retrospective analysis of outcomes of 15 consecutive patients with hematologic malignancies who experienced COVID-19 and subsequently underwent autologous (n = 8) or allogeneic (n = 7) HCT between June 17, 2020, and February 17, 2021. The cohort included patients with asymptomatic past infections or symptomatic COVID-19 disease. Data were obtained from chart review. Descriptive statistics were used to summarize patient characteristics. Among eight patients who underwent autologous HCT, four had a diagnosis of multiple myeloma and four had a diagnosis of non-Hodgkin's lymphoma. Four of these eight patients did not test positive for anti-SARS-CoV-2 IgG antibody at any point during the course of treatment. The other four patients had detectable anti-SARS-CoV-2 IgG antibodies before undergoing autologous HCT, but only two of these patients remained anti-SARS-CoV-2 IgG antibody-positive at their last follow-up. One patient died from progression of disease. Seven patients with prior COVID-19 underwent allogeneic HCT for acute lymphoblastic leukemia (n = 3), acute myelogenous leukemia (n = 1), chronic myelogenous leukemia in lymphoid blast crisis (n = 1), myelodysplastic syndrome (n = 1), or myelofibrosis (n = 1). Three of the seven patients tested positive for anti-SARS-CoV-2 IgG antibodies following the initial COVID-19 diagnosis; however, only one of these patients retained anti-SARS-CoV-2 IgG antibody following allogeneic HCT. One patient died of infection (fungal and Pneumocystis jirovecii pneumonia) occurring in the context of ongoing treatment for graft-versus-host disease. None of the 15 patients had recurrent COVID-19 infection. Based on our experience, autologous and allogeneic HCT can be safely performed in selected patients with previous COVID-19 infection.

Disease- and Therapy-Specific Impact on Humoral Immune Responses to COVID-19 Vaccination in Hematologic Malignancies

Coronavirus disease-19 (COVID-19) vaccine response data for patients with hematologic malignancy, who carry high risk for severe COVID-19 illness, are incomplete. In a study of 551 hematologic malignancy patients with leukemia, lymphoma, and multiple myeloma, anti-SARS-CoV-2 spike IgG titers and neutralizing activity were measured at 1 and 3 months from initial vaccination. Compared with healthy controls, patients with hematologic malignancy had attenuated antibody titers at 1 and 3 months. Furthermore, patients with hematologic malignancy had markedly diminished neutralizing capacity of 26.3% at 1 month and 43.6% at 3 months, despite positive seroconversion rates of 51.5% and 68.9% at the respective time points. Healthy controls had 93.2% and 100% neutralizing capacity at 1 and 3 months, respectively. Patients with leukemia, lymphoma, and multiple myeloma on observation had uniformly blunted responses. Treatment with Bruton tyrosine kinase inhibitors, venetoclax, phosphoinositide 3-kinase inhibitors, anti-CD19/CD20-directed therapies, and anti-CD38/B-cell maturation antigen-directed therapies substantially hindered responses, but single-agent immunomodulatory agents did not.

Significance

Patients with hematologic malignancy have compromised COVID-19 vaccine responses at baseline that are further suppressed by active therapy, with many patients having insufficient neutralizing capacity despite positive antibody titers. Refining vaccine response parameters is critical to guiding clinical care, including the indication for booster vaccines, for this vulnerable population.See related article by Tamari et al., p. 577. This article is highlighted in the In This Issue feature, p. 549.

Predictors of Humoral Response to SARS-CoV-2 Vaccination after Hematopoietic Cell Transplantation and CAR T-cell Therapy

Cellular therapies including allogeneic hematopoietic cell transplant (allo-HCT) and autologous hematopoietic cell transplant (auto-HCT) and chimeric antigen receptor (CAR) T-cell therapy render patients severely immunocompromised for extended periods after therapy, and data on responses to COVID-19 vaccines are limited. We analyzed anti-SARS-CoV-2 spike IgG Ab (spike Ab) titers and neutralizing Ab among 217 recipients of cellular treatments (allo-HCT, n = 149; auto-HCT, n = 61; CAR T-cell therapy, n = 7). At 3 months after vaccination, 188 patients (87%) had positive spike Ab levels and 139 (77%) had positive neutralization activity compared with 100% for both in 54 concurrent healthy controls. Time from cellular therapy to vaccination and immune recovery post-cellular therapy were associated with response. Vaccination against COVID-19 is an important component of post-cellular therapy care, and predictors of quantitative and qualitative response are critical in informing clinical decisions about optimal timing of vaccines and the requirement for booster doses.

Significance

Identifying predictors of response to vaccination against SARS-CoV-2 in patients following cellular therapy is critical to managing this highly vulnerable patient population. To date, this is the most comprehensive study evaluating quantitative and qualitative responses to vaccination, providing parameters most predictive of response and potentially informing booster vaccination strategies.See related article by Chung et al., p. 568. This article is highlighted in the In This Issue feature, p. 549.

Dynamics of minimal residual disease in patients with multiple myeloma on continuous lenalidomide maintenance: a single-arm, single-centre, phase 2 trial

Background Lenalidomide maintenance improves progression-free survival for patients with multiple myeloma, although its optimal duration is unknown. Clearance of minimal residual disease (MRD) in the bone marrow results in superior outcomes, although its attainment or sustainment does not alter clinical decision-making. Studies that have evaluated MRD serially are limited in length. We therefore aimed to evaluate longitudinal changes in MRD-status (dynamics) and their association with progression-free survival in patients with multiple myeloma.

METHODS

In this single-centre, single-arm, phase 2 study, we enrolled patients aged 18 years and older from the Memorial Sloan Kettering Cancer Center (New York, NY, USA) who had newly diagnosed multiple myeloma following unrestricted frontline therapy and an Eastern Cooperative Oncology Group Performance Status of 2 or lower, including patients who started maintenance before study enrolment. All participants received lenalidomide maintenance at 10 mg for 21 days of 28-day cycles until progression or unacceptable toxic effects for up to 5 years on protocol. The primary endpoint was progression-free survival at 60 months per protocol and key secondary endpoints were MRD rates after completion of the 12th, 24th, and 36th cycle of maintenance and the association between progression-free survival and annual measurement of MRD status. MRD was assessed from first-pull bone marrow aspirates at baseline and annually by flow cytometry per International Myeloma Working Group criteria, (limit of detection of at least 1 × 10^-5) up to a maximum of 5 years. Patients who completed at least four cycles of treatment were included in the analysis of the primary endpoint, and patients who had completed at least one dose of treatment on protocol were assessable for secondary endpoints. The study was registered at ClinicalTrials.gov, NCT02538198, and is now closed to accrual.

FINDINGS

Between Sept 8, 2015, and Jan 25, 2019, 108 patients (100 evaluable for the primary endpoint) were enrolled. Median follow-up was 40·7 months (95% CI 38·7-45·0). At 60 months, progression-free survival was 64% (95% CI 52-79). Median progression-free survival was unreached (95% CI unreached-unreached). MRD dynamics were assessed using 340 MRD assessments done over 5 years for 103 evaluable patients. Patients who sustained MRD negativity for 2 years (n=34) had no recorded disease progression at median 19·8 months (95% CI 15·8-22·3) past the 2-year maintenance landmark. By contrast, patients who lost their MRD-negative responses (n=10) were more likely to progress than those with sustained MRD negativity (HR infinite; p<0·0001) and those with persistent MRD positivity (HR 5·88, 95% CI 1·18-33·33; p=0·015) at the 2-year landmark. Haematological and non-haematological serious adverse events occurred in 19 patients (18%). The most common adverse events of grade 3 or worse were decreased lymphocyte count in 48 (44%) patients and decreased neutrophil count in 47 (44%) patients. One death occurred on study due to sepsis and heart failure and was considered unrelated to the study drug.

INTERPRETATION

Serial measurements of MRD allow for dynamic assessment of risk for disease progression. Early intervention should be investigated for patients with loss of MRD negativity. Sustained MRD positivity is not categorically an unfavourable outcome and might portend prolonged stability of low-level disease.

FUNDING

Memorial Sloan Kettering and Celgene.

Safety and Effectiveness of Weekly Carfilzomib, Lenalidomide, Dexamethasone, and Daratumumab Combination Therapy for Patients With Newly Diagnosed Multiple Myeloma: The MANHATTAN Nonrandomized Clinical Trial

Importance

Recently, the benefit of adding daratumumab to the proteasome inhibitor-based, 3-drug combination of bortezomib, lenalidomide, and dexamethasone for patients with newly diagnosed multiple myeloma who underwent high-dose melphalan chemotherapy and autologous hemopoietic cell transplant was assessed. Here, we examine the addition of daratumumab to the second-generation proteasome inhibitor-based, 3-drug combination of carfilzomib, lenalidomide, and dexamethasone.

Objective

To assess the safety and effectiveness of carfilzomib-lenalidomide-dexamethasone-daratumumab combination therapy for patients with newly diagnosed multiple myeloma, in the absence of high-dose melphalan chemotherapy and autologous hemopoietic cell transplant.

Design, Setting, and Participants

Clinical and correlative pilot study at the Memorial Sloan Kettering Cancer Center in New York, New York. Patients with newly diagnosed multiple myeloma were enrolled between October 1, 2018, and November 15, 2019. The median follow-up from start of treatment was 20.3 months (95% CI, 19.2-21.9 months).

Interventions

Eight 28-day cycles with intravenous carfilzomib, 20/56 mg/m2 (days 1, 8, and 15); oral lenalidomide, 25 mg, (days 1-21); dexamethasone, 40 mg weekly, orally or intravenously (cycles 1-4), and 20 mg after cycle 4; and intravenous daratumumab, 16 mg/kg (days 1, 8, 15, and 22 [cycles 1-2]; days 1 and 15 [cycles 3-6]; and day 1 [cycles 7 and 8]).

Main Outcomes and Measures

The primary end point was the minimal residual disease (MRD) rate, in the absence of high-dose melphalan chemotherapy and autologous hemopoietic cell transplant. Secondary end points included determining safety and tolerability, evaluating rates of clinical response per the International Myeloma Working Group, and estimating progression-free survival (PFS) and overall survival (OS) rates.

Results

Forty-one evaluable patients were enrolled (median age, 59 years; range, 30-70 years); 25 (61%) were female, and 20 (49%) had high-risk multiple myeloma. The primary end point (MRD negativity in the bone marrow; 10-5 sensitivity) was achieved in 29 of 41 patients (71%; 95% CI, 54%-83%), and therefore the trial was deemed successful. Median time to MRD negativity was 6 cycles (range, 1-8 cycles). Secondary end points of the overall response rate and the very good partial response or complete response rate were 100% (41 of 41 patients) and 95% (39 of 41 patients), respectively. At 11 months of the median follow-up, the 1-year PFS rate and the OS rate were 98% (95% CI, 93%-100%) and 100%, respectively. Most common (≥2 patients) grade 3 or 4 adverse events were neutropenia (12 patients [27%]), rash (4 patients [9%]), lung infection (3 patients [7%]), and increased alanine aminotransferase level (2 patients [4%]). There were no deaths.

Conclusions and Relevance

In this nonrandomized clinical trial, carfilzomib-lenalidomide-dexamethasone-daratumumab combination therapy was associated with high rates of MRD negativity in patients with newly diagnosed multiple myeloma and high rates of PFS.

Fecal microbiota diversity disruption and clinical outcomes after auto-HCT: a multicenter observational study

We previously described clinically relevant reductions in fecal microbiota diversity in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT). Recipients of high-dose chemotherapy and autologous HCT (auto-HCT) incur similar antibiotic exposures and nutritional alterations. To characterize the fecal microbiota in the auto-HCT population, we analyzed 1161 fecal samples collected from 534 adult recipients of auto-HCT for lymphoma, myeloma, and amyloidosis in an observational study conducted at 2 transplantation centers in the United States. By using 16S ribosomal gene sequencing, we assessed fecal microbiota composition and diversity, as measured by the inverse Simpson index. At both centers, the diversity of early pretransplant fecal microbiota was lower in patients than in healthy controls and decreased further during the course of transplantation. Loss of diversity and domination by specific bacterial taxa occurred during auto-HCT in patterns similar to those with allo-HCT. Above-median fecal intestinal diversity in the periengraftment period was associated with decreased risk of death or progression (progression-free survival hazard ratio, 0.46; 95% confidence interval, 0.26-0.82; P = .008), adjusting for disease and disease status. This suggests that further investigation into the health of the intestinal microbiota in auto-HCT patients and posttransplant outcomes should be undertaken.

Reduction of Opioid Use by Acupuncture in Patients Undergoing Hematopoietic Stem Cell Transplantation: Secondary Analysis of a Randomized, Sham-Controlled Trial

OBJECTIVE

To evaluate acupuncture as a nonpharmacologic intervention for pain management in patients undergoing hematopoietic stem cell transplantation (HSCT).

METHODS

Adult patients with multiple myeloma undergoing high-dose melphalan chemotherapy and autologous peripheral blood HSCT were randomized to receive either true (TA) or sham acupuncture (SA) once daily for five days starting on the day after chemotherapy. Use of pain medications and pain scores were assessed at baseline and at days 5, 15, and 30 after transplantation.

RESULTS

Among 60 evaluable subjects, the SA group (vs TA) had greater than five times odds of increasing pain medication use from baseline. Among patients who were opioid nonusers at baseline, all 15 patients in the TA group remained free from opioid use at the end of the study. In contrast, 20% of those in the SA group (four of the 20 patients) started to use opioids after chemotherapy and stem cell infusion (day 5) and 40% (eight of the 20) had become opioid users by day 30 after HSCT (Fisher exact test P = 0.006). Among patients who were taking opioids at baseline, 14% in the TA group vs 10% in the SA group increased opioid intake at day 5, and 21% (TA) vs 30% (SA) at day 30 (P = 0.86).

CONCLUSIONS

Acupuncture appears to significantly reduce the need for pain medications during HSCT and the number of post-HSCT opioid users among baseline opioid nonusers. It warrants further studies as an opioid-sparing intervention for pain in HSCT patients.

Prognostic Factors for Postrelapse Survival after ex Vivo CD34+-Selected (T Cell-Depleted) Allogeneic Hematopoietic Cell Transplantation in Multiple Myeloma

Allogeneic hematopoietic cell transplantation (alloHCT) for multiple myeloma (MM), with its underlying graft-versus-tumor capacity, is a potentially curative approach for high-risk patients. Relapse is the main cause of treatment failure, but predictors for postrelapse survival are not well characterized. We conducted a retrospective analysis to evaluate predictors for postrelapse overall survival (OS) in 60 MM patients who progressed after myeloablative T cell-depleted alloHCT. The median patient age was 56 years, and 82% had high-risk cytogenetics. Patients received a median of 4 lines of therapy pre-HCT, and 88% achieved at least a partial response (PR) before alloHCT. Of the 38% who received preemptive post-HCT therapy, 13 received donor lymphocyte infusions (DLIs) and 10 received other interventions. Relapse was defined as very early (<6 months; 28%), early (6 to 24 months; 50%), or late (>24 months; 22%). At relapse, 27% presented with extramedullary disease (EMD). The median postrelapse overall survival (OS) by time to relapse was 4 months for the very early relapse group, 17 months for the early relapse group, and 72 months for the late relapse group (P = .002). Older age, relapse with EMD, <PR before alloHCT, <PR by day +100, and no maintenance were prognostic for inferior postrelapse OS on univariate analysis. On multivariate analysis adjusted for age and sex, very early relapse (hazard ratio [HR], 4.37; 95% confidence interval [CI], 1.42 to 13.5), relapse with EMD (HR, 5.20; 95% CI, 2.10 to 12.9), and DLI for relapse prevention (HR, .11; 95% CI, 2.10 to 12.9) were significant predictors for postrelapse survival. Despite their shared inherent high-risk status, patients with MM have significantly disparate post-HCT relapse courses, with some demonstrating long-term survival despite relapse.

Accelerated single cell seeding in relapsed multiple myeloma

Multiple myeloma (MM) progression is characterized by the seeding of cancer cells in different anatomic sites. To characterize this evolutionary process, we interrogated, by whole genome sequencing, 25 samples collected at autopsy from 4 patients with relapsed MM and an additional set of 125 whole exomes collected from 51 patients. Mutational signatures analysis showed how cytotoxic agents introduce hundreds of unique mutations in each surviving cancer cell, detectable by bulk sequencing only in cases of clonal expansion of a single cancer cell bearing the mutational signature. Thus, a unique, single-cell genomic barcode can link chemotherapy exposure to a discrete time window in a patient′s life. We leveraged this concept to show that MM systemic seeding is accelerated at relapse and appears to be driven by the survival and subsequent expansion of a single myeloma cell following treatment with high-dose melphalan therapy and autologous stem cell transplant.

In multiple myeloma, disease progresses via seeding to different anatomic sites and clonal expansion. Here, utilising autopsy material, the authors show that systemic seeding accelerates at relapse following treatment.

Stem Cell Mobilization and Autograft Minimal Residual Disease Negativity with Novel Induction Regimens in Multiple Myeloma

Autologous stem cell transplantation (ASCT) remains the standard of care for transplantation-eligible patients with multiple myeloma (MM). Bortezomib with lenalidomide and dexamethasone (VRD) is the most common triplet regimen for newly diagnosed MM in the United States. Carfilzomib with lenalidomide and dexamethasone (KRD) has shown promising efficacy and may supplant VRD. We compared stem cell yields and autograft minimal residual disease (MRD)-negativity after VRD and KRD induction. Deeper responses (ie, very good partial response or better) were more common with KRD. Precollection bone marrow (BM) cellularity, interval from the end of induction therapy to start of stem cell collection, and method of stem cell mobilization were similar for the 2 cohorts. Days to complete collection was greater with KRD (2.2 days, versus 1.81 days with VRD), which more often required ≥3 days of apheresis. Precollection viable CD34⁺ cell content was greater with VRD, as was collection yield (11.11 × 10⁶, versus 9.19 × 10⁶ with KRD). Collection failure (defined as <2 × 10⁶ CD34⁺ cells/kg) was more frequent with KRD (5.4% versus .7% with VRD). The difference in stem cell yield between VRD and KRD is associated with the degree of lenalidomide exposure. Age ≥70 years predicted poorer collection for both cohorts. Stem cell autograft purity/MRD-negativity was higher with KRD (81.4%, versus 57.1% with VRD). For both cohorts, MRD-negativity was attained in a larger fraction of autografts than in precollection BM. For patients proceeding to ASCT, the time to neutrophil/platelet engraftment was comparable in the 2 study arms. In summary, our data demonstrate that KRD induces deeper clinical responses and greater autograft purity than VRD without compromising stem cell yield or post-transplantation engraftment kinetics.

Maintenance therapy and need for cessation studies in multiple myeloma: Focus on the future

With ten years of follow-up since the advent of the modern paradigm of combination induction therapy, consolidative autologous stem-cell transplant, and lenalidomide maintenance, median survival for multiple myeloma has increased to almost 50% at 10 years. Given this outlook, the overarching goal of maintenance therapy is to spare patients from the toxicities of aggressive or otherwise intrusive therapies while ideally extending survival or, at the least, extending progression-free survival or time until next treatment. This review will focus on the current landscape of maintenance therapies for multiple myeloma. The historical context and evidence for choice of agent, duration of treatment, and current strategies and ongoing trials will be discussed - as well as a focus on unmet needs. The case for studies investigating cessation of therapy and risk and response-adapted approaches will be underscored given that the current paradigm likely results in overtreatment for some patients.

Pilot Study of Bortezomib and Dexamethasone Pre- and Post-Risk-Adapted Autologous Stem Cell Transplantation in AL Amyloidosis

Treatment for AL amyloidosis aims to eradicate clonal plasma cells, thereby disrupting the amyloid deposition causing organ damage. Risk-adapted high-dose melphalan plus autologous stem cell transplantation (RA-ASCT) is an effective therapy. We conducted a prospective pilot analysis of a comprehensive approach using bortezomib and dexamethasone (BD) before and after RA-ASCT in 19 patients. BD induction (up to 3 cycles of bortezomib 1.3 mg/m² i.v. and dexamethasone 40 mg orally [p.o.] or i.v. on days 1, 4, 8, and 11) was followed by RA-ASCT and then BD consolidation (6 cycles of bortezomib 1.3 mg/m²i.v. and dexamethasone 20 mg p.o. or i.v. weekly for 4 weeks, every 12 weeks). The overall hematologic response rate (partial response or better) was 95%, including 37% minimal residual disease negative [MRD(-)] complete response (CR) by flow cytometry (sensitivity up to 1/10⁶ cells). At 2 years, progression-free survival (PFS) and overall survival were 68% (95% confidence interval [CI], 50% to 93%) and 84% (95% CI, 69% to 99%), respectively, with median duration of follow-up in survivors of 61 months (range, 42 to 84 months). In a landmark analysis, patients achieving MRD(-) CR had superior PFS (P= .008). This approach is safe and yields deep and durable remissions promoting organ recovery. Each treatment phase deepened the response. Future aims include improving the efficacy and toxicity of each phase.