Search

Competing Interests: Conflict of Interest Disclosure James R. Berenson received consultant fees, speakers’ bureau honoraria, and research funding from Bristol Myers Squibb.

Novel therapies are needed for patients with relapsed or refractory multiple myeloma (MM). We conducted a multicenter, phase 1 study in advanced hematological malignancies to assess the safety, efficacy, and recommended phase 2 dose (RP2D) of oral selinexor, a selective inhibitor of the nuclear export protein XPO1. In the dose-escalation phase, 25 patients with heavily pretreated MM (22) or Waldenstrom macroglobulinemia (3) were administered selinexor (3-60 mg/m 2 ) in 8 or 10 doses per 28-day cycle. In the dose-expansion phase, 59 patients with MM received selinexor at 45 or 60 mg/m 2 with 20 mg dexamethasone, twice weekly in 28-day cycles, or selinexor (40 or 60 mg flat dose) without corticosteroids in 21-day cycles. The most common nonhematologic adverse events (AEs) were nausea (75%), fatigue (70%), anorexia (64%), vomiting (43%), weight loss (32%), and diarrhea (32%), which were primarily grade 1 or 2. The most common grade 3 or 4 AEs were hematologic, particularly thrombocytopenia (45%). Single-agent selinexor showed modest efficacy with an objective response rate (ORR) of 4% and clinical benefit rate of 21%. In contrast, the addition of dexamethasone increased the ORR with all responses of ≥partial response occurring in the 45 mg/m 2 selinexor plus 20 mg dexamethasone twice weekly cohort (ORR = 50%). Furthermore, 46% of all patients showed a reduction in MM markers from baseline. Based on these findings, we conclude that selinexor in combination with dexamethasone is active in heavily pretreated MM and propose a RP2D of 45 mg/m 2 (80 mg) plus 20 mg dexamethasone given twice weekly. This trial was registered at clinicaltrials.gov as #NCT01607892., (© 2018 by The American Society of Hematology.)

Purpose: The US community-based, phase IIIB UPFRONT trial was designed to compare three frontline bortezomib-based regimens in transplantation-ineligible patients with myeloma., Patients and Methods: Patients (N = 502) were randomly assigned 1:1:1 to 24 weeks (eight 21-day cycles) of induction with bortezomib-dexamethasone (VD; n = 168; intravenous bortezomib 1.3 mg/m(2), days 1, 4, 8, and 11 plus oral dexamethasone 20 mg, days 1, 2, 4, 5, 8, 9, 11, and 12 [cycles 1 to 4], or 1, 2, 4, and 5 [cycles 5 to 8]), bortezomib-thalidomide-dexamethasone (VTD; n = 167; bortezomib and dexamethasone as before plus oral thalidomide 100 mg, days 1 to 21), or bortezomib-melphalan-prednisone (VMP; n = 167; bortezomib as before plus oral melphalan 9 mg/m(2) and oral prednisone 60 mg/m(2), days 1 to 4, every other cycle), followed by 25 weeks (five 35-day cycles) of bortezomib maintenance (1.6 mg/m(2), days 1, 8, 15, and 22). The primary end point was progression-free survival., Results: After 42.7 months' median follow-up, median progression-free survival with VD, VTD, and VMP was 14.7, 15.4, and 17.3 months, respectively; median overall survival was 49.8, 51.5, and 53.1 months, with no significant differences among treatments for either end point (global P = .46 and P = .79, respectively, Wald test). Overall response rates were 73% (VD), 80% (VTD), and 70% (VMP). Adverse events were more common with VTD than VD or VMP. Bortezomib maintenance was feasible without producing cumulative toxicity., Conclusion: Although all bortezomib-containing regimens produced good outcomes, VTD and VMP did not appear to offer an advantage over VD in transplantation-ineligible patients with myeloma treated in US community practice., (© 2015 by American Society of Clinical Oncology.)

Carfilzomib is a selective proteasome inhibitor that binds irreversibly to its target. In phase 1 studies, carfilzomib elicited promising responses and an acceptable toxicity profile in patients with relapsed and/or refractory multiple myeloma (R/R MM). In the present phase 2, multicenter, open-label study, 129 bortezomib-naive patients with R/R MM (median of 2 prior therapies) were separated into Cohort 1, scheduled to receive intravenous carfilzomib 20 mg/m(2) for all treatment cycles, and Cohort 2, scheduled to receive 20 mg/m(2) for cycle 1 and then 27 mg/m(2) for all subsequent cycles. The primary end point was an overall response rate (≥ partial response) of 42.4% in Cohort 1 and 52.2% in Cohort 2. The clinical benefit response (overall response rate + minimal response) was 59.3% and 64.2% in Cohorts 1 and 2, respectively. Median duration of response was 13.1 months and not reached, and median time to progression was 8.3 months and not reached, respectively. The most common treatment-emergent adverse events were fatigue (62.0%) and nausea (48.8%). Single-agent carfilzomib elicited a low incidence of peripheral neuropathy-17.1% overall (1 grade 3; no grade 4)-in these pretreated bortezomib-naive patients. The results of the present study support the use of carfilzomib in R/R MM patients. This trial is registered at www.clinicaltrials.gov as NCT00530816.

Background and objective: Bortezomib, an antineoplastic for the treatment of relapsed multiple myeloma and mantle cell lymphoma, undergoes metabolism through oxidative deboronation by cytochrome P450 (CYP) enzymes, primarily CYP3A4 and CYP2C19. Omeprazole, a proton-pump inhibitor, is primarily metabolized by and demonstrates high affinity for CYP2C19. This study investigated whether coadministration of omeprazole affected the pharmacokinetics, pharmacodynamics and safety profile of bortezomib in patients with advanced cancer. The variability of bortezomib pharmacokinetics with CYP enzyme polymorphism was also investigated. Patients and methods: This open-label, crossover, pharmacokinetic drug-drug interaction study was conducted at seven institutions in the US and Europe between January 2005 and August 2006. Patients who had advanced solid tumours, non-Hodgkin's lymphoma or multiple myeloma, were aged ≥18 years, weighed ≥50 kg and had a life expectancy of ≥3 months were eligible. Patients received bortezomib 1.3 mg/m2 on days 1, 4,8 and 11 for two 21-day cycles, plus omeprazole 40 mg in the morning of days 6-10 and in the evening of day 8 in either cycle 1 (sequence 1) or cycle 2 (sequence 2). On day 21 of cycle 2, patients benefiting from therapy could continue to receive bortezomib for six additional cycles. Blood samples for pharmacokinetic/pharmacodynamic evaluation were collected prior to and at various timepoints after bortezomib administration on day 8 of cycles 1 and 2. Blood samples for pharmacogenomics were also collected. Pharmacokinetic parameters were calculated by noncompartmental analysis of plasma concentration-time data for bortezomib administration on day 8 of cycles 1 and 2, using WinNonlin™ version 4.0.1.a software. The pharmacodynamic profile was assessed using a whole-blood 20S proteasome inhibition assay. Results: Twenty-seven patients (median age 64 years) were enrolled, 12 in sequence 1 and 15 in sequence 2, including eight and nine pharmacokinetic-evaluable patients, respectively. Bortezomib pharmacokinetic parameters were similar when bortezomib was administered alone or with omeprazole (maximum plasma concentration 120 vs 123 ng/mL; area under the plasma concentration-time curve from 0 to 72 hours 129 vs 135 ng • h/mL). The pharmacodynamic parameters were also similar (maximum effect 85.8% vs 93.7%; area under the percent inhibition-time curve over 72 hours 4052 vs 3910 %×h); the differences were not statistically significant. Pharmacogenomic analysis revealed no meaningful relationships between CYP enzyme polymorphisms and pharmacokinetic/pharmacodynamic parameters. Toxicities were generally similar between patients in sequence 1 and sequence 2, and between cycle 1 and cycle 2 in both treatment sequences. Among 26 evaluable patients, 13 (50%) were assessed as benefiting from bortezomib at the end of cycle 2 and continued to receive treatment. Conclusions: No impact on the pharmacokinetics, pharmacodynamics and safety profile of bortezomib was seen with coadministration of omeprazole. Concomitant administration of bortezomib and omeprazole is unlikely to cause clinically significant drug-drug interactions and is unlikely to have an impact on the efficacy or safety of bortezomib. [ABSTRACT FROM AUTHOR]