The Austin-based company was notified of a negative trend decision by the EMA, which makes it unlikely that a recommendation for use in humans would be received at the formal decision vote scheduled in May and additional steps to gain marketing approval are necessary.
John Simard, chief executive, said the company was disappointed.
“We believe that the data speak in a clear and resounding voice to clinical relevance of a new antibody therapy in advanced colorectal cancer.
"Findings from our Phase III study show that we have developed an important endpoint and methodology to evaluate anti-cancer therapy in advanced stage disease and that our monoclonal antibody represents a breakthrough treatment in patients with advanced colorectal cancer.”
An appeal is possible and Simard said as the decision was based on an oral meeting the company may go down this route 'at the appropriate time'.
XBiotech had been a strong performer ahead of the decision but its share price dropped US$6.80 to US$10.30 today.