Grade 4 neutropenia occurred in 16 patients in each group; grade 4 thrombocytopenia in 10 in the chemotherapy group vs. 11 in the iniparib group. There were no grade 4 anemia or leukopenia events in either arm.
Two deaths occurred with chemotherapy alone vs. three with iniparib, all due to disease progression, Dr. O’Shaughnessy said. In all, 14% in the iniparib group and 27% in the chemotherapy alone group discontinued treatment because of adverse events. Dose reductions were similar between study arms.
Dr. O’Shaughnessy reported no conflicts of interest. Several coinvestigators are employees of study sponsor Bipar Sciences Inc., which is developing iniparib with its parent company, Sanofi-Aventis.