Roy, Vivek

Key Points The combination of ixazomib and dexamethasone has clinical activity in patients with relapsed and or refractory multiple myeloma. Higher dose of ixazomib leads to improved response rates but with higher rates of treatment related adverse events.

BACKGROUNDNational Cancer Institute (NCI)/National Comprehensive Cancer Network (NCCN)–designated cancer centers (CCs) offer patients state‐of‐the‐art treatment, but their impact on multiple myeloma (MM) patient outcomes has not been evaluated.METHODSAdult MM patients diagnosed between 1973 and 2011 were identified from the Surveillance, Epidemiology, and End Results database and were stratified by the county of residence at the time of diagnosis and the year of CC designation. The influence of NCI/NCCN CC access, race, and the year of diagnosis on overall survival (OS) was evaluated with a Cox regression model.RESULTSA statistically significant OS improvement was noted in patients diagnosed after 1995 with access to 2 or more NCI CCs overall (P = .002 for 1996‐2002; P < .001 for 2003‐2011) and by race for whites (hazard ratio [HR] for 1996‐2002, 0.85; 95% confidence interval [CI], 0.78‐0.91; HR for 2003‐2011, 0.85; 95% CI, 0.79‐0.91) but not for nonwhites. For NCCN access, improvement was seen in 1996‐2002 (P = .003), in 2003‐2011 (P < .001), and by race for whites (HR, 0.917; 95% CI, 0.88‐0.95) and nonwhites (0.94; 95% CI, 0.89‐0.99), but within nonwhites, this was true only for African Americans (AAs; HR, 0.88; 95% CI, 0.81‐0.97) and not for Asians, Hispanics, or Native Americans.CONCLUSIONSImprovement in OS was seen in MM patients diagnosed after 1995 with access to 1 NCCN CC or 2 or more NCI CCs. NCI access benefited only whites, whereas NCCN access benefited only white and AA patients. No OS benefit was seen for any subgroup with access to only 1 NCI center. Eliminating racial disparities in health care access and utilization is needed to improve outcomes. Cancer 2016;122:618–625. © 2015 American Cancer Society.

Bendamustine is a multifunctional alkylating agent with single agent activity in myeloma. We designed the current phase 1/2 trial to determine the maximum tolerated doses (MTD) of bendamustine that can be safely combined with lenalidomide and dexamethasone and to assess the safety and efficacy of the combination. Patients with relapsed MM following at least 1 prior therapy, but no more than four lines of prior therapy and with measurable disease were enrolled. Bendamustine 75 mg/m2 given on days 1 and 2, lenalidomide 25 mg given days 1–21 and dexamethasone 40 mg on days 1, 8, 15, and 22, was the recommended Phase 2 dose. Seventy‐one patients were accrued: 21 on Phase 1 and 50 on Phase 2. The median age was 62.3 years; patients had a median of three prior lines of therapy (range 1–4), with over 70% of the patients having received prior lenalidomide, bortezomib, and/or peripheral blood stem cell transplant. Thirty‐four of 70 (49%) patients had a confirmed partial response or better, including 20 patients (29%) with a very good partial response or better. An additional 4 patients had a minor response, translating to an overall 55% clinical benefit rate. Grade 3 or higher toxicity was seen in 96% of patients, with ≥grade 3 hematologic in 94% and nonhematologic in 50%. The median progression free survival was 11.8 months and the median duration of response was 23 months. The combination of bendamustine, lenalidomide, and dexamethasone is very effective in relapsed multiple myeloma with high response rates and durable responses Am. J. Hematol. 90:1106–1110, 2015. © 2015 Wiley Periodicals, Inc.

BACKGROUNDPoor marrow cellularity alone cannot explain poor hematopoietic progenitor cell (HPC) mobilization. This study assessed the role of CD8+ T cells in HPC cell mobilization and engraftment.STUDY DESIGN AND METHODSMobilization and engraftment were assessed in 192 autologous HPC donors. CD34+, CD4+, and CD8+ T‐cell contents in apheresis products were evaluated. Using a chemotaxis assay, we assessed the effect of purified autologous CD8+ T cells from low and high mobilizers on HPC migration from high to low stromal cell–derived factor (SDF‐1α) concentration gradients. We also assessed CD8+ T‐cell content association with days to neutrophil engraftment.RESULTSThe median number of CD34+ cells/kg was 4.7 × 106. Patients were categorized according to their total CD34+ cell collection quartile distribution into low, moderate, and high mobilizers. We found that HPC products from low mobilizers contained more CD8+ T cells than HPC products from moderate and high mobilizers. Chemotaxis assays showed depletion of CD8+ T cells enhances HPC mobilization independent of SDF‐1α concentration. Neutrophil engraftment analysis showed that the higher the CD8+ T‐cell content per unit CD34+ cell, the faster the rate of engraftment.CONCLUSIONOur findings suggest CD8+ T cells inhibit HPC mobilization and facilitate homing and engraftment.

Key Points Dinaciclib is a novel cdk inhibitor that demonstrates single agent activity in myeloma. Dinaciclib has a safety profile that is easily manageable.

SummaryMultiple myeloma, the second most common haematological malignancy in the U.S., is currently incurable. Disruption of the intrinsic apoptotic pathway by BCL2 and MCL1 upregulation is observed in >80% of myeloma cases and is associated with an aggressive clinical course. Remarkably, there is no approved drug with the ability to target BCL2 or MCL1. Thus, we investigated the anti‐tumour effects of a pan‐BCL2 inhibitor, AT‐101, which has high binding specificity for BCL2 and MCL1 in preclinical models of plasma cell cancers (Multiple myeloma and Waldenström macroglobulinaemia). Gene expression and immunoblot analysis of six plasma cell cancer models showed upregulation of BCL2 family members. AT‐101 was able to downregulate BCL2 and MCL1 in all plasma cell cancer models and induced apoptotic cell death in a caspase‐dependent manner by altering mitochondrial membrane permeability. This cytotoxic effect and BCL2 downregulation were further potentiated when AT‐101 was combined with lenalidomide/dexamethasone (LDA). NanoString nCounter mRNA quantification and Ingenuity Pathways Analysis revealed differential changes in the CCNA2, FRZB, FYN, IRF1, PTPN11 genes in LDA‐treated cells. In summary, we describe for the first time the cellular and molecular events associated with the use of AT‐101 in combination with lenalidomide/dexamethasone in preclinical models of plasma cell malignancy.

Abstract Smoldering multiple myeloma (SMM) bridges the gap between monoclonal gammopathy of undetermined significance (a mostly premalignant disorder) and active multiple myeloma (MM). Until recently, no interventional study in patients with SMM showed improved overall survival (OS) with therapy as compared with observation. A report from the PETHEMA-GEM (Programa Español de Tratamientos en Hematologica) group described both fewer myeloma-related events and better OS among patients with high-risk SMM who were treated with lenalidomide and dexamethasone. This unique study prompted us to review current knowledge about SMM and address the following questions: (1) Are there patients currently defined as SMM who should be treated routinely? (2) Should the definitions of SMM and MM be reconsidered? (3) Has the time come when not treating is more dangerous than treating? (4) Could unintended medical harm result from overzealous intervention? Our conclusion is that those patients with the highest-risk SMM (extreme bone marrow plasmacytosis, extremely abnormal serum immunoglobulin free light chain ratio, and multiple bone lesions detected only by modern imaging) should be reclassified as active MM so that they can receive MM-appropriate therapy and the paradigm of careful observation for patients with SMM can be preserved.