XBiotech Completes Enrollment in Global Phase III Study using Xilonix Monotherapy to Treat Advanced Colorectal Cancer

AUSTIN, Texas, Dec. 07, 2016 -- XBiotech Inc. (NASDAQ:XBIT), developer of True Human™ therapeutic antibodies, today announced that enrollment has been completed in its randomized, double-blind, placebo-controlled Phase III study evaluating Xilonix as a treatment for advanced colorectal cancer. The Phase III study is being conducted under Fast Track designation from the FDA and involves over 600 advanced cancer patients from 18 countries world-wide. The Company reports that the first interim analysis allowing an assessment by the Data Monitoring Committee (DMC) of both safety and efficacy is expected as early as first quarter 2017.

“We have achieved another significant milestone in our oncology program,” stated John Simard, President & CEO of XBiotech. “Our team has remained on schedule with this complex project and we now look forward to an interim analysis early next year.”

The double-blind, placebo-controlled Phase III study is randomized 2:1 with patients receiving Xilonix or placebo plus best supportive care. Patients are required to have metastatic colorectal cancer, and are required to have failed regimens that include flouropyrimidines, oxaliplatin, irinotecan, and Cetuximab or Panitumumab for patients with KRAS mutation. Patients continue on study until there is evidence of radiographic progression. The primary endpoint of this study is overall survival, with secondary endpoints including objective response rate, progression free survival, change in lean body mass as measured by dual energy X-ray absorptiometry (DEXA), and patient reported quality of life using the validated EORTC QLQ C30 questionnaire. There are two scheduled interim analyses and a final analysis. The study may be stopped for efficacy at either interim analysis, which would potentially enable an early submission of a request for marketing authorization. Patients are otherwise followed for up to 18 months in order to determine overall survival and the study is powered for 552 events at study conclusion.

About True Human™ Therapeutic Antibodies
Unlike previous generations of antibody therapies, XBiotech’s True Human™ antibodies are derived without modification from individuals who possess natural immunity to certain diseases. With discovery and clinical programs across multiple disease areas, XBiotech’s True Human antibodies have the potential to harness the body’s natural immunity to fight disease with increased safety, efficacy and tolerability.

About XBiotech
XBiotech is a fully integrated global biosciences company dedicated to pioneering the discovery, development and commercialization of therapeutic antibodies based on its True Human™ proprietary technology. XBiotech currently is advancing a robust pipeline of antibody therapies to redefine the standards of care in oncology, inflammatory conditions and infectious diseases. Headquartered in Austin, Texas, XBiotech also is leading the development of innovative biotech manufacturing technologies designed to more rapidly, cost-effectively and flexibly produce new therapies urgently needed by patients worldwide. For more information, visit www.xbiotech.com.

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