European regulators have agreed to review an investigational treatment for advanced colorectal cancer being developed by XBiotech, which said it now expects to submit a marketing authorisation application shortly.

Xilonix is a first-in-class ‘true human’ monoclonal antibody that neutralises the biological activity of interleukin-1_. The drug differs from so-called fully human monoclonal antibodies in that it is derived from a mature human antibody sequence with no in vitro sequence modifications to improve binding affinity.

A recent Phase III trial, involving colorectal cancer patients with inoperable or metastatic disease who have failed all conventional therapies, indicated that Xilonix was able to control tumour-related symptoms associated with morbidity and death.

Findings also suggest that the antibody therapy “appears to lack the frank toxicity of many other anti-cancer agents, and that the therapy may not cause the negative haematological effects that result in immunosuppression, eliminating a troubling toxicity and life-threatening risk factor of other anti-cancer therapies used to treat advanced disease,” the firm noted. 

The data show a 76% relative improvement in response rate in patients treated with the antibody, as compared to placebo, while secondary endpoints - control of thrombocytosis and systemic inflammation - which are known prognosticators of overall survival, were also significantly improved in treated patients compared to controls, raising hopes of a new approach for patients left with little treatment options.