XBiotech has discontinued the Phase III XCITE study evaluating its lead True Human™ anti-interleukin-1α monoclonal antibody (mAb) Xilonix™ in the treatment of patients with advanced colorectal cancer (CRC) on efficacy grounds. The study’s independent data monitoring committee (IDMC) recommended stopping the trial after it reported that findings from a second, unblinded analysis of trial data weren’t sufficient to meet efficacy or the threshold for continuation.
The global placebo-controlled XCITE study had been evaluating Xilonix in patients with advanced CRC who had failed prior chemotherapy regimens and cetuximab or panitumumab therapy. The primary endpoint was overall survival, and secondary endpoints included change in lean body mass, patient-reported quality of life, progression-free survival, and objective response rate.
XBiotech president and CEO, John Simard, stated that while the company was “obviously disappointed” with the XCITE findings, it would continue to seek regulatory approval based on data from its previous, successfully completed European study, “which demonstrated control of debilitating symptoms in CRC.” Despite these positive trial data, just last month the European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) recommended against approving Xilonix for the CRC indication. The previous month, an EMA committee had queried the clinical relevance of the treatment.
XBiotech is developing a clinical and preclinical pipeline of True Human™ antibody therapeutics for oncology, infectious disease, cardiovascular, and other indications. In April, the firm reported what study investigators called encouraging results from a small, first-in-human Phase I/II trial evaluating the FDA Fast Tracked antibody candidate 514G3 for treating Staphylococcus aureus bloodstream infections.
