Kourelis, Taxiarchis

AbstractIn this phase 1/2 study, carfilzomib was added to high‐dose melphalan conditioning prior to autologous stem cell transplantation (ASCT) in patients with multiple myeloma that had been treated with ≤2 prior lines of therapy. Carfilzomib was escalated at doses of 27, 36, 45, and 56 mg/m2 on days −6, −5, −2, and −1 before ASCT in the phase 1 component of the study. In addition, all the patients received melphalan 100 mg/m2 on days −4 and −3. The primary endpoint of the phase 1 component was to identify the maximum tolerated dose, and the primary endpoint of the phase 2 component was the rates of complete response (≥CR) at 1 year after ASCT. The phase 1 dose escalation cohort included 14 patients, and 35 patients were included in the phase 2 cohort. The maximum tested dose was 56 mg/m2 (MTD). The median time from diagnosis to study enrollment was 5.8 (range 3.4–88.4) months, and 16% of patients had obtained a ≥CR prior to ASCT. The best response within 1 year after ASCT was a ≥ CR rate in 22% for the entire cohort, and 22% for patients treated at the MTD. The ≥VGPR rates improved from 41% before ASCT to 77% by 1 year after ASCT. One patient had a grade 3 renal adverse event, and renal function returned to baseline with supportive care. The rate of grade 3–4 cardiovascular toxicity was 16%. The addition of carfilzomib to melphalan conditioning was safe and resulted in deep responses after ASCT.

Abstract Patients with multiple myeloma (MM) who do not respond to initial therapy have worse outcomes than primary responders, and effective treatments are lacking in this population. However, the outcomes of primary refractory disease in the modern treatment era have not yet been studied. We reviewed patients with MM treated with triplet/quadruplet therapy at our institution to assess the incidence of primary refractory disease and the impact of salvage therapies in this population. We identified 1127 patients, of whom 1086 were evaluated for hematologic responses after 4 to 6 cycles. Of these, 93.3% (1013) had evidence of response, whereas 6.7% (73) had primary refractory disease. With a median overall survival (OS) of 51.3 months, patients with primary refractory disease had an increased risk of shorter survival in univariable and multivariable analyses (hazard ratio [HR], 3.5 [95% confidence interval (CI), 2.5-4.9]; HR, 4.3 [95% CI, 2.6-6.9], respectively). In the subgroup analysis of patients with primary refractory disease, those who received second-line autologous stem cell transplantation (ASCT) had increased second progression-free survival (20.9 vs 8.1 months; P < .01) and second OS (74.7 vs 31.3 months; P = .02) compared with patients who did not. We conclude that early progression remains a significant factor for shorter OS in the current era, and salvage ASCT could be the most beneficial option for this population.

VEXAS is caused by somatic mutations in UBA1 (UBA1mut) and characterized by heterogenous systemic auto-inflammation and progressive hematologic manifestations, meeting criteria for myelodysplastic syndrome (MDS) and plasma cell dyscrasias. The landscape of myeloid-related gene mutations leading to typical clonal hematopoiesis (CH) in these patients is unknown. Retrospectively, we screened 80 VEXAS patients for CH in their peripheral blood (PB) and correlated findings with clinical outcomes in 77. UBA1mutwere most common at hotspot p.M41 (median variant allele frequency/VAF = 75%). Typical CH mutations co-occurred with UBA1mut in 60% of patients, mostly in DNMT3A and TET2, and were not associated with inflammatory or hematologic manifestations. In prospective single-cell proteogenomic sequencing (scDNA), UBA1mutwas the dominant clone, present mostly in branched clonal trajectories. Based on integrated bulk and scDNA analyses, clonality in VEXAS followed two major patterns: with either typical CH preceding UBA1mutselection in a clone (Pattern 1), or occurring as an UBA1mutsubclone or in independent clones (Pattern 2). VAF in PB differed markedly between DNMT3A and TET2 clones (median VAF of 25% vs 1%). DNMT3A and TET2 clones associated with hierarchies representing patterns 1 and 2, respectively. Overall survival for all patients was 60% at 10 years. Transfusion-dependent anemia, moderate thrombocytopenia, and typical CH mutations, each correlated with poor outcome. In VEXAS, UBA1mut cells are the primary cause of systemic inflammation and marrow failure, being a new molecularly defined somatic entity associated with MDS. VEXAS-associated MDS is distinct from classical MDS in its presentation and clinical course.

Abstract Multiple myeloma (MM) bone disease is a significant cause of morbidity but there is a paucity of data on the impact of malignant plasma cells on adjacent trabecular bone within the BM. Here, we characterize the proteome of trabecular bone tissue from BM biopsies of 56 patients with monoclonal gammopathy of undetermined significance (MGUS), smoldering (SMM), newly diagnosed (NDMM), relapsed MM (RMM), and normal controls. Proteins involved in extracellular matrix (ECM) formation and immunity pathways were decreased in SMM and active MM. Among the proteins most decreased were immunoglobulins, type IV collagen, and TIMP3, suggesting increased immunoparesis and decreased ECM remodelling within trabecular bone. Proteins most increased in SMM/MM were APP (enhances osteoclast activity), ENPP1 (enhances bone mineralization), and MZB1 (required for normal plasmablast differentiation). Pathway analyses showed that proteins involved in gamma -carboxylation, a pathway implicated in osteocalcin function, osteoblast differentiation, and normal hematopoiesis, were also overexpressed in SMM/MM. This study is the first comprehensive proteomic atlas of the BM bone proteome in dysproteinemias. We identify new key proteins and pathways for MM bone disease and potentially impaired hematopoiesis, and show for the first time that gamma -carboxylation pathways are increased in the bone tissue of SMM/MM.

Abstract Lenalidomide‐containing (R) triplet and quadruplet regimens are the standard of care for multiple myeloma (MM) and have been shown to increase the risk of thrombosis. The association between thromboembolism (TE) and survival in the novel multidrug era is not yet delineated. In this study, we evaluated the incidence of TE during the first year of MM diagnosis, its association with the type of induction regimen, and its impact on overall survival. We studied 672 newly diagnosed MM (NDMM) patients who received a triplet or quadruplet lenalidomide‐based induction at the Mayo Clinic, Rochester. TE was diagnosed in 83 patients (12.4%). Of these, 56 (8.3%) had a deep venous thrombosis (DVT), 23 (3.4%) had a pulmonary embolism (PE) with or without the DVT, and 4 (0.6%) patients had a stroke. Carfilzomib‐Rd (KRd) had the highest risk of TE (21.1%, 18/85), followed by quadruplets (11.1%, 5/45), bortezomib‐Rd (9.6%, 51/531), and 0/11 (0%), treated with other lenalidomide‐containing regimens. The difference in TE risk between KRd and the other regimens was statistically significant (OR = 2.6, p < .01). Nine patients developed a TE before being exposed to any treatment. Survival was significantly lower among patients that developed a TE (66 vs. 133 months, p < .01). The association of TE with reduced survival demonstrated in univariate analysis (HR = 2.2, 95% CI = 1.6–3.3) was maintained in the multivariable analysis adjusted for high‐risk interphase fluorescence in situ hybridization (FISH), sex, age, receipt of an upfront transplant, the response at induction, and the International Staging System (ISS) (HR = 2.61, CI = 1.74–3.9). We conclude that TE is an important aspect of MM management, and effective management is especially relevant in the novel treatment era.

AbstractPatients with multiple myeloma (MM) have a lower efficacy from COVID‐19 vaccination and a high rate of mortality from COVID‐19 in hospitalized patients. However, the overall rate and severity of COVID‐19 infection in all settings (including non‐hospitalized patients) and the independent impact of plasma cell‐directed therapies on outcomes needs further study. We reviewed the medical records of 9225 patients with MM or AL amyloidosis (AL) seen at Mayo Clinic Rochester, Arizona, and Florida between 12/01/2019 and 8/31/2021 and identified 187 patients with a COVID‐19 infection (n = 174 MM, n = 13 AL). The infection rate in our cohort was relatively low at 2% but one‐fourth of the COVID‐19 infections were severe. Nineteen (10%) patients required intensive care unit (ICU) admission and 5 (3%) patients required mechanical ventilation. The mortality rate among hospitalized patients with COVID‐19 was 22% (16/72 patients). Among patients that were fully vaccinated at the time of infection (n = 12), two (17%) developed severe COVID‐19 infection, without any COVID‐related death. On multivariable analysis, treatment with CD38 antibody within 6 months of COVID‐19 infection [Risk ratio (RR) 3.6 (95% CI: 1.2, 10.5), p = .02], cardiac [RR 4.1 (95% CI: 1.3, 12.4), p = .014] or pulmonary comorbidities [RR 3.6 (95% CI 1.1, 11.6); p = .029] were independent predictors for ICU admission. Cardiac comorbidity [RR 2.6 (95% CI: 1.1, 6.5), p = .038] was an independent predictor of mortality whereas MM/AL in remission was associated with lower mortality [RR 0.4 (95% CI: 0.2–0.8); p = .008].

Two Letters to Blood address the risks of COVID-19 in populations with precursors of hematological disease. In the first article, Miller and colleagues report on whether clonal hematopoiesis of intermediate potential (CHIP) is associated with adverse outcomes with COVID-19, finding no association between CHIP and 28-day mortality while providing data indirectly linking IL-6 signaling and patient outcomes. In the second article, Ho and colleagues investigate the outcomes of patients with monoclonal gammopathy of undetermined significance (MGUS) with COVID-19, reporting that one-fourth had a severe infection and that on multivariable analysis, adverse outcomes are more likely if immunoparesis is present.

Abstract Bortezomib, a proteasome inhibitor (PI), has shown efficacy in the treatment of newly diagnosed and relapsed light chain (AL) amyloidosis, and is often used in combination with cyclophosphamide and dexamethasone. Ixazomib is the first oral PI to be approved in routine practice but has not yet been evaluated in the upfront treatment setting. Newly diagnosed AL amyloidosis patients with measurable disease and adequate organ function were enrolled. The primary objective was to determine the hematologic response rate of ixazomib in combination with cyclophosphamide and dexamethasone. Treatment was given for 12 cycles, followed by ixazomib maintenance until progression. Thirty-five patients were included; their median age was 67 years, and 69% were male. Major organ involvement included heart (66%) and kidneys (54%). A median of 4 induction cycles (range, 1-12) were administered. The overall hematologic response to induction was 63% and included complete response in 11.4% and very good partial response in 37.1% of patients. One patient was upstaged to complete response during maintenance. The most common reason for going off study was the institution of alternate therapy (61%). With a median follow-up of 29.7 months for the living patients, the 2-year progression-free survival and overall survival were 74% and 78%, respectively. The median time to alternate therapy was 7.5 months. Grade ≥3 hematologic and nonhematologic adverse events occurred in 23% and 49% of patients. Given ixazomib’s favorable toxicity profile, which is an important advantage for the typically frail AL population, further evaluation of ixazomib in other combinations in the upfront setting is warranted. This trial was registered at www.clinicaltrials.gov as #NCT01864018.

SummaryBelantamab mafodotin (BLMF) is a B‐cell maturation antigen‐directed antibody‐drug conjugate, recently approved for advanced multiple myeloma (MM). The impact of BLMF‐induced ocular toxicity on patient outcomes is unknown. We studied a cohort of 38 consecutively seen patients treated with BLMF outside of trials. Of those, 75% experienced ocular toxicity, with 69% developing keratopathy. Among patients requiring ocular toxicity‐related permanent BLMF discontinuation (14%) or dose reduction (11%), 70% had progression of MM within a median of 3 months (95% confidence interval: 0.2–not reached) following BLMF interruption or dose reduction. Ocular toxicity is a major deterrent to the continuous use of BLMF in routine clinical practice. Measures to successfully prevent and mitigate ocular toxicity should be developed to achieve the full potential of this agent.

Abstract Almost all patients with multiple myeloma (MM) eventually relapse, either asymptomatically or with end-organ damage. However, it remains unclear whether initiating therapy at the time of biochemical progression (BP) improves the outcomes compared with initiating therapy at the clinical progression (CP) stage. Here, we retrospectively assessed 1347 patients with relapsed MM. Most progressions were BP (60.4%); 39.6% had CP. The most prevalent symptoms at relapse were new or evolving bone disease (80.9%), anemia (38.0%), and renal failure (12.7%). Patients with BP had longer median time from second-line treatment to the next treatment compared with patients who had CP (17.0 vs 9.6 months; P &lt; .001) as well as longer median overall survival from first relapse (59.4 vs 26.2 months; P &lt; .001). Male sex (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.02-2.18; P = .04), plasma cell labeling index ≥2% (OR, 1.58; 95% CI, 1.02-2.45; P = .04), and extramedullary disease at diagnosis (OR, 1.84; 95% CI, 1.08-3.13; P = .03) were associated with higher risk of CP, whereas very good partial remission or better had decreased risk of CP (OR, 0.62; 95% CI, 0.43-0.91; P = .02). To conclude, patients with CP have inferior postprogression outcomes compared with patients who have BP. Patients with deeper response to first-line therapy are less likely to develop CP. The presence of a specific CRAB (C, hypercalcemia; R, renal failure; A, anemia; B, bone disease) symptom at diagnosis predicts for the development of similar CRAB symptoms at relapse.