Balixafortide fails to meet co-primary endpoint in HER2 negative breast cancer trial

Published: 30 June 2021

Disappointing late-stage results from the phase III Fortress trial have Polyphor considering its options.

In the phase III Fortress study, Swiss biotech Polyphor’s immunotherapy drug balixafortide (POL6326) was tested in combination with eribulin (Eisia) versus eirbulin alone in patients with late-stage HER2 negative breast cancer. 

Balixafortide plus eribulin showed no improvement in objective response rate compared with eribulin alone when used as a third line treatment or later. Clinical benefit rate, a key secondary endpoint, was observed in 16.7% of patients in the balixafortide plus eribulin arm, versus 19.6% in the eribulin arm.

In response to the disappointing results, the company’s board of directors will undertake a “strategic assessment and will consider a full range of options regarding the future of the company”, according to a company press release. Polyphor will also continue to review and analyse the data, with plans to make a decision about the future of the study by July.