Multiple Myeloma Phase III Trial - Vorinostat Achieved Primary Endpoint

MSD announced the results of their Phase III study of vorinostat at the 53rd Annual Meeting of the American Society of Hematology (ASH). Vorinostat, designed for treatment in patients with progressivemultiple myeloma, has met its primary endpoint in a Phase III study for investigational use in combination with bortezomib (Velcade®) by demonstrating a 23% reduction in the risk of progression in comparison to the standard therapy of bortezomib (p=0.01). 

VANTAGE 088 (Vorinostat in Combination with Bortezomib in Patients with Relapsed/Refractory Multiple Myeloma: A Global Randomized Phase III Trial) is one of the largest trials conducted in patients with relapsed/refractory myeloma. The randomized, double-blinded, placebo controlled study was designed to show improvement in progression-free survival (PFS) in patients suffering from progressive multiple myeloma with at least one prior therapy, who were either treated with a combination of vorinostat and bortezomib, or with bortezomib alone. 

The findings revealed that from 637 patients overall, the combination group had 417 PFS events with a 23% reduction in the risk of progression compared with a hazard ratio of 0.774 (0.64-0.94, p=0.01) in the bortezomib alone group. 

The researchers noted that the average PFS in the vorinostat and bortezomib combination group was 7.6 months compared with 6.8 months in the bortezomib alone group. 

The drugs were generally tolerated in the vorinostat and bortezomib combination group with adverse events consisting of thrombocytopenia, diarrhea, nausea, vomiting and fatigue. The researchers observed no difference in discontinuation rates due to an adverse event for vorinostat (21%) compared to the placebo group (22%).

At ASH, MSD also presented full results from VANTAGE 095 (Vorinostat in Combination with Bortezomib in Salvage Multiple Myeloma Patients), a global Phase IIb trial that involved 143 patients. The researchers determined the primary endpoint as overall response rate (ORR). According to the European Group for Blood and Marrow Transplant (EBMT), the vorinostat and bortezomib combination group achieved an ORR of 11.3%. 

Written by Petra Rattue