Key Points Panobinostat + bortezomib + dexamethasone recaptures responses in heavily pretreated, bortezomib-refractory multiple myeloma patients.

Autologous hematopoietic cell transplantation (AHCT) for plasma cell myeloma is performed less often in people >70 years old than in people ≤70 years old. We analyzed 11,430 AHCT recipients for plasma cell myeloma prospectively reported to the Center for International Blood and Marrow Transplant Research between 2008 and 2011, representing the majority of US AHCT activity during this period. Survival (OS) was compared in 3 cohorts: ages 18 to 59 years (n = 5818), 60 to 69 years (n = 4666), and >70 years (n = 946). Median OS was not reached for any cohort. In multivariate analysis, increasing age was associated with mortality (P = .0006). Myeloma-specific mortality was similar among cohorts at 12%, indicating an age-related effect on nonmyeloma mortality. Analyses were performed in a representative subgroup comparing relapse rate, progression-free survival (PFS), and nonrelapse mortality (NRM). One-year NRM was 0% for age >70 years and 2% for other ages (P = not significant). The three-year relapse rate was 56% in age 18 to 59 years, 61% in age 60 to 69 years, and 63% age >70 (P = not significant). Three-year PFS was similar at 42% in age 18 to 59 years, 38% in age 60 to 69 years, and 33% in age >70 years (P = not significant). Postrelapse survival was significantly worse for the older cohort (P = .03). Older subjects selected for AHCT derived similar antimyeloma benefit without worse NRM, relapse rate, or PFS.

Background Autologous hematopoietic stem cell transplantation (AHCT) improves survival in patients with multiple myeloma (MM) but is associated with morbidity and non-relapse mortality (NRM). Hematopoietic cell transplant comorbidity index (HCT-CI) was shown to predict risk of NRM and survival after allogeneic transplantation. We tested the utility of HCT-CI as a predictor of NRM and survival in patients with MM undergoing AHCT. Methods We analyzed outcomes of 1156 patients of AHCT after high-dose melphalan (MEL) reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). Individual comorbidities were prospectively collected at the time of AHCT. The impact of HCT-CI and other potential prognostic factors including Karnofsky performance score (KPS) on NRM and survival were studied in multivariate Cox regression models. Results HCT-CI score was 0, 1, 2, 3 and > 3 in 42%, 18%, 13%, 13% and 14% respectively. Subjects were stratified into 3 risk groups; HCT-CI 0 (42%) vs. HCT-CI 1–2 (32%) vs. HCT-CI >2 (26%). Higher HCT-CI was associated with lower KPS <90 (33% in HCT-CI of 0 vs. 50% in HCT-CI >2). HCT-CI score >2 was associated with MEL dose-reduction (22% vs. 10% in score 0 cohort). One-year NRM was low at 2% (95% CI 1–4%) and did not correlate with HCT-CI score (p value 0.9). On multivariate analysis, overall survival (OS) was inferior in groups with HCT-CI of 1–2 (RR 1.37, [95% CI: 1.01–1.87], p=0.04) and HCT-CI >2 (RR 1.5 [95% CI: 1.09–2.08], p=0.01). OS was also inferior with KPS <90 (p< 0.001), IgA subtype (p< =0.001), those receiving >1 pre-transplant induction regimen (p =0.007) and those with resistant disease at the time of AHCT (p <0.001). Conclusion AHCT for MM is associated with low NRM and death is predominantly related to disease progression. Although a higher HCT-CI score did not predict NRM, it was associated with inferior survival.

Introduction: PF-06863135 (PF-3135) is a bispecific, humanized, monoclonal antibody (mAb) consisting of BCMA- and CD3-targeting arms paired on an IgG2a backbone by hinge-mutation technology. PF-3135 binds BCMA+ myeloma cells and CD3+ T cells with affinities of 20 pM and ~40 nM, respectively (Panowski et al. Blood 2016). We report here findings from the dose-escalation portion of an ongoing, multi-center, open-label, phase I study (NCT03269136) of PF-3135 in patients with RRMM. Methods: Adult patients (≥18 years of age) with RRMM, previously treated with a proteasome inhibitor, an immunomodulatory drug, and an anti-CD38 mAb, received escalating, intravenous (IV) doses of PF-3135, once weekly. Prior BCMA-targeted bispecific T-cell engager or chimeric antigen receptor T-cell (CART) treatment was allowed by protocol. Patients had measurable disease per the International Myeloma Working Group (IMWG) updated criteria 2014. A modified toxicity probability interval method (mTPI), targeting a dose-limiting toxicity (DLT) rate of 25% (equivalence interval ± 5%) was used for dose escalation. The primary study objectives are to assess PF-3135 safety and tolerability, to determine the maximum tolerated dose (MTD) and select the recommended phase II dose (RP2D). Secondary objectives include evaluation of anti-myeloma activity, pharmacokinetics (PK), and immunogenicity of PF-3135. Results: As of April 9, 2019, 17 patients had received once weekly, non-continuous, IV infusion of PF-3135 in 6 dose-escalation groups. The majority were men (71%). The median age was 61 yrs (range, 47-82 yrs) and median disease duration since onset was 7 yrs (range, 1.1-13.3 yrs). Ten (59%) patients had ≥1 chromosomal abnormality and 5 (29%) had a normal karyotype (status not known for 2 [12%] patients). The median number of prior anti-myeloma therapies was 11; 5 (29%) patients had received prior BCMA-targeted therapy. Eight (47%) patients had relapsed MM and 8 (47%) had refractory disease (recurrence type not known for 1 [6%] patient). Ten (59%) patients experienced treatment-related (TR) AEs of any grade. Most TRAEs were grade 1-2, including cytokine release syndrome (CRS, 24%), thrombocytopenia (24%), anemia (18%), and pyrexia (18%). Three (18%) patients had grade 3 TRAEs (increased alanine aminotransferase/aspartate aminotransferase, leukocytopenia, neutropenia, and lymphopenia). One patient treated at the highest dose level, who had received prior BCMA CART therapy, developed treatment-related febrile neutropenia, a DLT, which may have been related to CRS and borderline/low neutrophil count at baseline. None of the patients had grade 4-5 TRAEs or discontinued treatment due to a TRAE. The median duration of treatment was 4 (range, 2-12) actual dosing days. Sixteen of the 17 patients were evaluable for response. At the time of data cut-off, one (6%) patient had a minimal response and 6 (35%) patients had stable disease (SD) across dose levels, as best response by investigator IMWG assessment; 9 (53%) patients experienced disease progression. The clinical benefit rate (defined as best response ≥SD) was 41% (95% CI: 18.4%, 67.1%). Conclusions: Treatment with IV PF-3135 was well tolerated at the dose levels evaluated. The observed CRS events were moderate and dose-dependent. Additional dose cohorts are accruing. The latest clinical, biomarker, and PK data will be presented for this ongoing study. Disclosures Raje: Medscape: Honoraria; Research to Practice: Honoraria; Takeda: Consultancy, Honoraria; Merck: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; AstraZeneca: Research Funding. Jakubowiak:Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Consultancy, Honoraria; Juno: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; SkyLineDx: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; KaryoPharm Therapeutics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Gasparetto:Janssen: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; BMS: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; Celgene: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed . Cornell:KaryoPharm: Consultancy; Takeda: Consultancy. Krupka:Pfizer: Employment, Equity Ownership. Navarro:Pfizer: Employment, Equity Ownership. Forgie:Pfizer: Employment, Equity Ownership. Udata:Pfizer: Employment, Equity Ownership. Basu:Pfizer: Employment, Equity Ownership. Chou:Pfizer: Employment, Equity Ownership. Leung:Pfizer: Employment, Equity Ownership. Lesokhin:BMS: Consultancy, Honoraria, Research Funding; Serametrix Inc.: Patents & Royalties; Takeda: Consultancy, Honoraria; Genentech: Research Funding; Juno: Consultancy, Honoraria; GenMab: Consultancy, Honoraria; Janssen: Research Funding. OffLabel Disclosure: PF-06863135, investigational agent

Early mortality (EM; death ≤ 6 months from diagnosis) has been reported in several newly diagnosed multiple myeloma (NDMM) trials. Before the era of novel agents, the incidence was 10%‐14%. Causes of death included infections/pneumonia, renal failure, refractory disease, and cardiac events. Staging systems, such as the revised International Staging System (r‐ISS), and prognostic factors including cytogenetics, lactate dehydrogenase levels, and myeloma‐specific factors, are useful to assess overall prognosis; however, they cannot predict EM. We evaluated patients treated with novel agents in the Connect MM® Registry and identified risk factors of the EM cohort. Eligible patients were enrolled in the registry within 60 days of diagnosis. Univariate and multivariate analyses were conducted to evaluate associations between baseline characteristics and EM. Prediction matrices for EM were constructed from a logistic model. Between September 2009 and December 2011, 1493 patients were enrolled in the registry and had adequate follow‐up. Of these patients, 102 (6.8%) had EM and 1391 (93.2%) survived for > 180 days. Baseline factors significantly associated with increased EM risk included age > 75 years, higher Eastern Cooperative Oncology Group performance status, lower EQ‐5D mobility score, higher ISS stage, lower platelet count, and prior hypertension. Renal insufficiency trended toward increased EM risk. These risk factors were incorporated into a prediction matrix for EM. The EM prediction matrix uses differential weighting of risk factors to calculate EM risk in patients with NDMM. Identifying patients at risk for EM may provide new opportunities to implement patient‐specific treatment strategies to improve outcomes.