A phase 1/2 study of ixazomib in place of bortezomib or carfilzomib in a subsequent line of therapy for patients with multiple myeloma refractory to their last bortezomib or carfilzomib combination regimen.

Identifying effective combination regimens is a high priority in multiple myeloma (MM), as most patients eventually become refractory to their current treatments. In this study, we investigated whether the proteasome inhibitor (PI) ixazomib could delay disease progression among patients who failed regimens containing another PI, bortezomib or carfilzomib. This phase 1/2, multicenter, open-label, nonrandomized study enrolled patients who were refractory to a previous regimen containing bortezomib or carfilzomib. Patients continued the other anti-MM drugs in the regimen at the same doses and frequencies. Patients with combination regimens with unknown maximum tolerated dose (MTD) of ixazomib were enrolled in phase 1, with ixazomib starting at 3 mg and then dose escalated to 4 mg. Patients on regimens with a known ixazomib MTD were enrolled in phase 2. Primary endpoints were overall response rate (ORR), clinical benefit rate (CBR), adverse events (AEs), and determination of maximum tolerated dose (MTD). Of the 46 patients enrolled, 39 were evaluable for efficacy. ORR and CBR were 12.8% and 17.9%, respectively. Ixazomib appeared to be well tolerated as a replacement for carfilzomib and bortezomib, with 23.9% of patients experiencing at least one grade ≥3 serious adverse event (SAE) and 37.0% experiencing at least one grade ≥3 AE. The most common grade ≥3 AEs were hyponatremia (8.7%), anemia (8.7%), dyspnea (8.7%), thrombocytopenia (6.5%), dehydration (4.3%), and pneumonia (4.3%). The results indicate that ixazomib is not an effective replacement for bortezomib or carfilzomib for patients with MM who have previously relapsed on other bortezomib/carfilzomib-containing regimens.

Safety of BTZ retreatment for patients with low-grade peripheral neuropathy during the initial treatment.

OBJECTIVE: Neuropathy is an important complication that may limit treatment options for patients with multiple myeloma. Previous studies have focused on treatment efficacy and have shown that retreatment with bortezomib (BTZ) is an effective treatment option. The goal of this study was to focus on the clinical manifestations of peripheral neuropathy (PN) and to retrospectively compare the incidence and severity of PN between the initial BTZ regimen and upon retreatment. Furthermore, this study evaluated how certain factors affect BIPN, which will help determine what conditions should be considered prior to retreatment. METHODS: Charts were reviewed from 93 patients who were retreated with a BTZ-containing regimen after previously being treated with this drug. RESULTS: Among the patients who developed PN, most patients in the study had low-grade neuropathy during the initial BTZ treatment (n = 52, 68%). The results showed no evidence of cumulative toxicity, and there was no significant difference in the incidence and severity of PN upon retreatment. Factors such as the presence of baseline PN, number of prior treatments, dose of BTZ, and comorbidities did not increase the severity of PN upon retreatment. The lapse of time between the two regimens also did not affect the severity of PN. CONCLUSION: The results suggest that retreatment with BTZ may be a feasible option, without additional risks of PN, for MM patients even with peripheral neuropathy during their initial treatment with this drug.

Randomized phase II study of carboplatin and etoposide with or without obatoclax mesylate in extensive-stage small cell lung cancer.

OBJECTIVE: This randomized phase II study assessed the efficacy and safety of obatoclax mesylate, a small-molecule Bcl-2 inhibitor, added to carboplatin/etoposide chemotherapy as initial treatment for extensive-stage small-cell lung cancer (ES-SCLC). MATERIALS AND METHODS: Chemotherapy-naïve subjects with ES-SCLC and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2 received carboplatin/etoposide with (CbEOb) or without (CbE) obatoclax for up to six cycles. Responders to CbEOb could receive maintenance obatoclax until disease progression. The primary endpoint was objective response rate (ORR). RESULTS: 155 subjects (median age 62, 58% male, 10% ECOG PS 2) were treated with CbEOb (n=77) or CbE (n=78); 65% and 59% of subjects, respectively, completed six cycles. ORR was 62% with CbEOb versus 53% with CbE (1-sided p=0.143). Clinical benefit (ORR+ stable disease) trended better with CbEOb (81% versus 68%; p=0.054). Median progression-free survival (PFS) and overall survival (OS) were 5.8 months (95% confidence interval [CI]: 5.3-6.5) and 10.5 months (8.9-13.8) with CbEOb and 5.2 months (95% CI: 4.1-5.7) and 9.8 months (7.2-11.2) with CbE. Median OS was 10.5 months (95% CI: 8.9-13.8) and 9.8 months (7.2-11.2) with a nonsignificant hazard ratio for OS, 0.823; 1-sided p=0.121. Grade 3/4 adverse events (AEs) were primarily hematologic and similar in frequency between treatment arms. Obatoclax-related somnolence and euphoria were grade 1/2, transient, and did not require treatment discontinuation. CONCLUSION: Obatoclax was well tolerated when added to carboplatin/etoposide in first-line treatment of ES-SCLC, but failed to significantly improve ORR, PFS, or OS.

Zoledronic acid markedly improves bone mineral density for patients with monoclonal gammopathy of undetermined significance and bone loss.

PURPOSE: Patients with monoclonal gammopathy of undetermined significance (MGUS) have increased rates of bone resorption, osteopenia, osteoporosis, and risk of fractures. This study was undertaken to determine the efficacy and safety of zoledronic acid for patients with MGUS and enhanced bone loss. EXPERIMENTAL DESIGN: In this phase II open-label study, 54 patients with MGUS and osteopenia or osteoporosis were administered zoledronic acid 4 mg i.v. at 0, 6, and 12 months. The primary efficacy end point was bone mineral density, assessed using a dual-energy X-ray absorptiometry scan in the lumbar (L)-spine done at screening and at 13 months (1 month after the final zoledronic acid infusion). RESULTS: At study end for all patients (N = 54), L-spine T-scores improved by a median of +0.27 (range, -0.38 to +3.91), corresponding to a median increase in bone mineral density of +15.0% (range, -18.0% to +1,140.0%; P < 0.0001). Hip T-scores improved by a median of +0.10 (range, -2.40 to +2.03), corresponding to a median increase of +6.0% (range, -350.0% to +165.0%). During the study, no new fractures, osteonecrosis of the jaw, or significant renal adverse events were reported. CONCLUSIONS: Zoledronic acid administered i.v. at a dosage of 4 mg every 6 months for three doses total was well-tolerated and substantially improved bone mineral density for patients with MGUS and bone loss. Zoledronic acid may be effective for the prevention of new fractures in this high-risk population.