Efficacy and safety of once-weekly and twice-weekly bortezomib in patients with relapsed systemic AL amyloidosis: results of a phase 1/2 study

AbstractThis first prospective phase 2 study of single-agent bortezomib in relapsed primary systemic AL amyloidosis evaluated the recommended (maximum planned) doses identified in phase 1 testing (1.6 mg/m2 once weekly [days 1, 8, 15, and 22; 35-day cycles]; 1.3 mg/m2 twice weekly [days 1, 4, 8, and 11; 21-day cycles]). Among all 70 patients enrolled in the study, 44% had ≥ 3 organs involved, including 73% and 56% with renal and cardiac involvement. In the 1.6 mg/m2 once-weekly and 1.3 mg/m2 twice-weekly groups, the hematologic response rate was 68.8% and 66.7% (37.5% and 24.2% complete responses, respectively); median time to first/best response was 2.1/3.2 and 0.7/1.2 months, and 78.8% and 75.5% had response durations of ≥ 1 year, respectively. One-year hematologic progression-free rates were 72.2% and 74.6%, and 1-year survival rates were 93.8% and 84.0%, respectively. Outcomes appeared similar in patients with cardiac involvement. Among all 70 patients, organ responses included 29% renal and 13% cardiac responses. Rates of grade ≥ 3 toxicities (79% vs 50%) and discontinuations/dose reductions (38%/53% vs 28%/22%) resulting from toxicities appeared higher with 1.3 mg/m2 twice-weekly versus 1.6 mg/m2 once-weekly dosing. Both bortezomib dose schedules represent active, well-tolerated regimens in relapsed AL amyloidosis. This study was registered at www.clinicaltrials.gov as #NCT00298766

A Phase 2 Study of Bortezomib in Relapsed, Refractory Myeloma

BACKGROUND Bortezomib, a boronic acid dipeptide, is a novel proteasome inhibitor that has been shown in preclinical and phase 1 studies to have antimyeloma activity. METHODS In this multicenter, open-label, nonrandomized, phase 2 trial, we enrolled 202 patients with relapsed myeloma that was refractory to the therapy they had received most recently. Patients received 1.3 mg of bortezomib per square meter of body-surface area twice weekly for 2 weeks, followed by 1 week without treatment, for up to eight cycles (24 weeks). In patients with a suboptimal response, oral dexamethasone (20 mg daily, on the day of and the day after bortezomib administration) was added to the regimen. The response was evaluated according to the criteria ofthe European Group for Blood and Marrow Transplantation and confirmed by an independent review committee. RESULTS Of 193 patients who could be evaluated, 92 percent had been treated with three or more ofthe major classes of agents for myeloma, and in 91 percent, the myeloma was refractory to the therapy received most recently. The rate of response to bortezomib was 35 percent, and those with a response included 7 patients in whom myeloma protein became undetectable and 12 in whom myeloma protein was detectable only by immuno-fixation. The median overall survival was 16 months, with a median duration of response of 12 months. Grade 3 adverse events included thrombocytopenia (in 28 percent of patients), fatigue (in 12 percent), peripheral neuropathy (in 12 percent), and neutropenia (in 11 percent). Grade 4 events occurred in 14 percent of patients. CONCLUSIONS Bortezomib, a member of a new class of anticancer drugs, is active in patients with relapsed multiple myeloma that is refractory to conventional chemotherapy

Bortezomib plus melphalan and prednisone compared with melphalan and prednisone in previously untreated multiple myeloma: updated follow-up and impact of subsequent therapy in the phase III VISTA trial

[EN]The purpose of this study was to confirm overall survival (OS) and other clinical benefits with bortezomib, melphalan, and prednisone (VMP) versus melphalan and prednisone (MP) in the phase III VISTA (Velcade as Initial Standard Therapy in Multiple Myeloma) trial after prolonged follow-up, and evaluate the impact of subsequent therapies. Previously untreated symptomatic patients with myeloma ineligible for high-dose therapy received up to nine 6-week cycles of VMP (n = 344) or MP (n = 338). With a median follow-up of 36.7 months, there was a 35% reduced risk of death with VMP versus MP (hazard ratio, 0.653; P < .001); median OS was not reached with VMP versus 43 months with MP; 3-year OS rates were 68.5% versus 54.0%. Response rates to subsequent thalidomide- (41% v 53%) and lenalidomide-based therapies (59% v 52%) appeared similar after VMP or MP; response rates to subsequent bortezomib-based therapy were 47% versus 59%. Among patients treated with VMP (n = 178) and MP (n = 233), median survival from start of subsequent therapy was 30.2 and 21.9 months, respectively, and there was no difference in survival from salvage among patients who received subsequent bortezomib, thalidomide, or lenalidomide. Rates of adverse events were higher with VMP versus MP during cycles 1 to 4, but similar during cycles 5 to 9. With VMP, 79% of peripheral neuropathy events improved within a median of 1.9 months; 60% completely resolved within a median of 5.7 months. VMP significantly prolongs OS versus MP after lengthy follow-up and extensive subsequent antimyeloma therapy. First-line bortezomib use does not induce more resistant relapse. VMP used upfront appears more beneficial than first treating with conventional agents and saving bortezomib- and other novel agent-based treatment until relapse

Bortezomib plus rituximab versus rituximab in patients with high-risk, relapsed, rituximab-na\uefve or rituximab-sensitive follicular lymphoma: subgroup analysis of a randomized phase 3 trial

BACKGROUND: The randomized phase 3 LYM3001 trial in relapsed follicular lymphoma (FL) demonstrated higher overall (ORR) and complete response (CR) rates and prolonged progression-free survival (PFS) with bortezomib-rituximab versus rituximab. We report findings in high-risk patients (FL International Prognostic Index [FLIPI] score 653, and high tumor burden by modified Groupe d'Etude des Lymphomas Folliculaires [GELF] criteria). METHODS: Patients aged 6518 years with grade 1/2 FL, 651 measurable lesion, and documented relapse or progression following prior therapy, rituximab-na\uefve or rituximab-sensitive, were enrolled at 164 centers in 29 countries across Europe, the Americas, and Asia-Pacific. Patients were randomized (1:1) to five 5-week cycles of bortezomib-rituximab (bortezomib 1.6 mg/m2, days 1, 8, 15, and 22, all cycles; rituximab 375 mg/m2, days 1, 8, 15, and 22, cycle 1, and day 1, cycles 2-5; N=336) or rituximab alone (N=340). Randomization was stratified by FLIPI score, prior rituximab, time since last dose of anti-lymphoma therapy, and geographical region. The primary endpoint of the study was PFS. RESULTS: 103 bortezomib-rituximab and 98 rituximab patients had high-risk FL. The ORR was 59% versus 37% (p=0.002), the CR/CRu rate was 13% versus 6% (p=0.145), and the durable response rate was 45% versus 26% (p=0.008) with bortezomib-rituximab versus rituximab. Median PFS was 9.5 versus 6.7 months (hazard ratio [HR] 0.667, p=0.012) with bortezomib-rituximab versus rituximab; median time to progression was 10.9 versus 6.8 months (HR 0.656, p=0.009); median time to next anti-lymphoma treatment was 14.8 versus 9.1 months (HR 0.762, p=0.103); and the 1-year Overall Survival rate was 83.1% versus 76.6%. Overall, 51% of bortezomib-rituximab and 32% of rituximab patients reported grade 653 adverse events, including neutropenia (18%, 6%), anemia (4%, 5%), diarrhea (8%, 0%), thrombocytopenia (5%, 2%), and sensory neuropathy (1%, 0%). CONCLUSIONS: High-risk FL patients treated with bortezomib-rituximab had significantly higher ORR and longer PFS than patients receiving rituximab alone, with greater clinical benefit than in the overall study population; additional toxicity was acceptable and did not affect treatment feasibility. TRIAL REGISTRATION: The phase 3 LYM3001 trial is registered with ClinicalTrials.gov, with the identifier NCT00312845

Myeloma cell dynamics in response to Treatment supports a model of hierarchical differentiation and clonal evolution

[Purpose]: Since the pioneering work of Salmon and Durie, quantitative measures of tumor burden in multiple myeloma have been used to make clinical predictions and model tumor growth. However, such quantitative analyses have not yet been performed on large datasets from trials using modern chemotherapy regimens. [Experimental Design]: We analyzed a large set of tumor response data from three randomized controlled trials of bortezomib-based chemotherapy regimens (total sample size n = 1,469 patients) to establish and validate a novel mathematical model of multiple myeloma cell dynamics. [Results]: Treatment dynamics in newly diagnosed patients were most consistent with a model postulating two tumor cell subpopulations, >progenitor cells> and >differentiated cells.> Differential treatment responses were observed with significant tumoricidal effects on differentiated cells and less clear effects on progenitor cells. We validated this model using a second trial of newly diagnosed patients and a third trial of refractory patients. When applying our model to data of relapsed patients, we found that a hybrid model incorporatingboth a differentiation hierarchy and clonal evolution best explains the response patterns. [Conclusions]: The clinical data, together with mathematical modeling, suggest that bortezomib-based therapy exerts a selection pressure on myeloma cells that can shape the disease phenotype, thereby generating further inter-patient variability. This model may be a useful tool for improving our understanding of disease biology and the response to chemotherapy regimens.The authors acknowledge the support from the Dana-Farber Cancer Institute Physical Sciences-Oncology Center (U54CA193461).Peer Reviewe