Real world data on outcomes of anti-CD38 antibody treated, including triple class refractory, patients with multiple myeloma: a multi-institutional report from the Canadian Myeloma Research Group (CMRG) Database.

Multiple myeloma (MM) remains incurable despite the availability of novel agents. This multi-center retrospective cohort study used the Canadian Myeloma Research Group Database to describe real-world outcomes of patients withanti-CD38 monoclonal antibody (mAb) refractory MM subsequently treated with standard of care (SoC) regimens. Patients with triple class refractory (TCR) disease (refractory to a proteasome inhibitor, immunomodulatory drug, and anti-CD38 mAb) were examined as a distinct cohort. Overall, 663 patients had disease progression on anti-CD38 mAb therapy, 466 received further treatment (346 with SoC regimens were included, 120 with investigational agents on clinical trial and were excluded). The median age at initiation of subsequent SoC therapy of 67.9 (range 39.6-89.6) years with a median of 3 prior lines (range 1-9). The median PFS and OS from the start of subsequent therapy was 4.6 (95% CI 4.1-5.6) months and 13.3 (95% CI 10.6-16.6) months, respectively. The median PFS and OS of patients with TCR disease (n = 199) was 4.4 (95% CI 3.6-5.3) months and 10.5 (95% CI 8.5-13.8) months. Our results reinforce that real-world patients with relapsed MM, particularly those with TCR disease, have dismal outcomes. There remains an urgent unmet need for the development of and access to effective therapeutics for these patients.

CyBorD induction therapy in clinical practice.

Cyclophosphamide, bortezomib and dexamethasone (CyBorD) is a highly active three-drug induction regimen for untreated transplant-eligible multiple myeloma patients. Although CyBorD has been evaluated only in the phase 2 setting in a limited number of patients, its high efficacy and ease of administration have led to its widespread use. Given that clinical trial efficacy can overestimate real-life effectiveness, we reviewed our institutional experience with 109 newly diagnosed patients who were treated with CyBorD in a non-clinical trial setting. After a median of four cycles, overall response rate (ORR) and very good partial response rate or better (⩾VGPR) were 95 and 66%, respectively, comparable to phase 2 studies of CyBorD and other three/four-drug induction regimens. All patients subsequently underwent successful stem cell collection and upgraded responses to ORR 98% and ⩾VGPR 79% post transplant. At a median follow-up of 19.8 months after diagnosis, the 2-year OS probability was 95.3% (95%CI: 89-98). The presence of concurrent plasmacytoma at diagnosis was the only prognostic factor predicting poorer survival (HR=5.56; 95%CI: 0.92-33.74; P=0.03). CyBorD was well-tolerated, with no severe peripheral neuropathy and minimal hematologic toxicity. Therefore, CyBorD is a convenient, well-tolerated, highly effective induction regimen in preparation for autologous SCT in real-life clinical practice.

Efficacy, toxicity and mortality of autologous SCT in multiple myeloma patients with dialysis-dependent renal failure.

Numerous studies have reported the feasibility and safety of autologous SCT (ASCT) in patients with multiple myeloma (MM) and mild to moderate renal impairment, but there are limited data in dialysis-dependent patients. In this retrospective study, we reviewed the toxicities and efficacy outcomes of 33 MM patients with dialysis-dependent renal failure who underwent ASCT at our institution from 1998 to 2012. The most common grade 3 non-hematologic toxicities were mucositis (49%), infection (15%) and bleeding (6%). Atrial dysrhythmias (24%) and delirium (30%) of all grades were also common. Hematologic toxicities included febrile neutropenia (88%); and RBC and platelet transfusions were required by 71 and 100% of patients, respectively. Transplant-related mortality (TRM) was high at 15%, predominantly caused by septic shock. Response to ASCT was at least VGPR (very good PR) in 50%, PR in 46.2% and stable disease (SD) in 3.8%. Median OS was 5.6 years, comparable to our overall institutional data. Overall, seven patients became dialysis independent. We conclude that ASCT can be an effective treatment for dialysis-dependent MM patients, with high response rates and survival. However, toxicities and a high TRM are observed indicating that further studies are needed to enhance the safety of this approach.

Influence of type II diabetes on arterial tone and endothelial function in murine mesenteric resistance arteries.

An arteriograph was used to assess myogenic tone, smooth muscle contractility and the influence of endothelial function on mesenteric resistance artery reactivity in insulin-resistant mice (C57BL/KsJ-db/db) and age- and gender-matched wild-type mice. Increases in transmural pressure induced myogenic tone in arteries from both control and db/db mice. At 12 and 16 weeks of age, greater tone developed in diabetic than in control mice. In control, but not in db/db mice, pretreatment of arteries with L-NAME potentiated myogenic tone. Indomethacin and SQ29548 (PGH2/TXA2 receptor antagonist) had no efffect in control, but inhibited myogenic tone in db/db mice. Endothelium-dependent vasodilation induced by acetylcholine and bradykinin, was depressed in db/db mice and potentiated by SQ29548 and LY333531 (protein kinase C(beta) inhibitor). Messenger RNA expression levels for PKC(beta) were over-expressed 2.5-fold in db/db relative to those in control mice. However, expression levels of mRNA for eNOS, PKC(alpha), and PKC(xi) were similar in the db/db and control mice. Collectively, these results suggest that the greater myogenic tone in resistance arteries from diabetic mice may be attributable, to greater amounts of one or more vasoconstricting prostanoids. Our data indicate that in diabetic mice, basal and agonist-stimulated NO releases are depressed and NO-mediated vasorelaxation in these mice may be countered by an endogenous vasoconstrictive prostanoid. This prostanoid-induced vasoconstriction is mediated by a PKC(beta)-dependent mechanism. Therefore, heightened activation of PKC(beta) and release of a vasoconstrictor prostanoid could play a role in endothelial dysfunction associated with type II diabetes.

Hepatic over-expression of peroxisome proliferator activated receptor gamma2 in the ob/ob mouse model of non-insulin dependent diabetes mellitus.

Studies of the molecular basis of insulin resistance have focused on the peroxisome proliferator activated receptor gamma (PPARgamma, gamma1 and gamma2). The aim of this study was to determine whether the insulin resistance in liver of diabetic animals is associated with abnormal expression of these receptors. PPARgamma mRNA and protein expression levels were quantified in liver of 9-week-old male ob/ob mice as a model of diabetes and compared to age- and gender-matched wild type control animals of the same genetic background. Semi-quantitative reverse transcription-polymerase chain reaction, using 18S rRNA as an internal standard, indicated that PPARgamma2 mRNA was significantly upregulated in ob/ob liver vs. that in wild type mice. Western blotting revealed greater immunoreactivity of PPARgamma2 in liver from ob/ob mice relative to that in wild type mice. An index of insulin resistance (product of serum glucose and insulin concentration) was correlated with liver PPARgamma2 mRNA expression (r = 0.776; p < 0.001). The findings that liver PPARgamma2 expression is (1) significantly elevated in the ob/ob model of diabetes and (2) positively associated with an index of insulin resistance, suggests a possible compensatory response through which type II diabetic and obese organisms strive to maintain insulin sensitivity of the liver.