Polyphor provides update on the phase III FORTRESS study of balixafortide in patients with advanced HER2 negative breast cancer.

At the primary analysis, balixafortide plus eribulin showed no improvement in the objective response rate (ORR) compared with eribulin alone (13.0% versus 13.7%; p=1.00) in the third line and later population (n=330 patients) followed for a minimum of 6 months. The clinical benefit rate, a key secondary endpoint indicating a stable disease or any confirmed response for a duration of at least 6 months as assessed by the IRC (independent radiological committee) was observed in 16.7% of patients in the balixafortide plus eribulin arm and 19.6% in the eribulin alone arm. The study confirmed the positive safety and tolerability profile of balixafortide in line with the previously reported Phase Ib study.

Polyphor will continue to analyze the data,review with the experts and will decide about the future of the study in mid-July. The board of directors is undergoing a strategic assessment and will consider a full range of options regarding the future of the company and will provide an update not later than end of July.