Breakthrough Results from Phase 2 Clinical Trial of Bermekimab in the Treatment of Atopic Dermatitis (AD) to be Presented on March 2, 2019 at American Academy of Dermatology Annual Meeting

• Rapid and significant reduction in skin lesions, 66% (p<0.001) and 76% (p<0.001) mean reduction in EASI score in 4 and 7 weeks, respectively.
   
• Rapid and significant resolution of worst itch and pain, 57% (p<0.001) and 61% (p<0.001) mean reduction within 4 weeks, respectively.
   
• Substantial mean reduction of worst itch and pain 71% (p<0.001) and 84% (p<0.001) within 7 weeks, respectively.

AUSTIN, Texas, March 01, 2019 (GLOBE NEWSWIRE) -- XBiotech (NASDAQ: XBIT) announced today that breakthrough results from its Phase 2 clinical trial of its antibody therapy, bermekimab, are being presented tomorrow at a late-breaking oral presentation during the annual meeting of the American Academy of Dermatology (AAD) being held  in Washington, DC. The presentation titled, “Bermekimab is a Rapid and Effective Treatment for Atopic Dermatitis (AD)” will take place on Saturday, March 2 at 1:10pmET in Ballroom A and will be presented by international dermatology expert, and lead researcher in the development of approved therapies for atopic dermatitis, Eric Simpson, M.D, M.C.R. Professor of Dermatology at Oregon Health & Science University, School of Medicine.

The results being presented by Dr. Simpson demonstrate that bermekimab treatment resulted in rapid and significant improvement of disease in patients with moderate-to-severe AD. After only 7 weeks of treatment, 71% of patients that received a 400mg bermekimab weekly regimen had at least 75% reduction in their disease, as measured by the Eczema Area and Severity Index (EASI) score (this compares to 44-51% of patients achieving 75% improvement in EASI score after 16 weeks therapy as reported for two Phase III clinical trials for the existing FDA approved biological drug for AD). Moreover, within 7 weeks, using patient reported Numerical Rating Scale (NRS) for itch and pain,  patients receiving the 400mg bermekimab treatment regimen had 71% reduction in itch and an 84% reduction in pain (this compares to 36-41% reduction in itch [pain was not reported] after 16 weeks of treatment with the existing approved therapy for AD).

XBiotech CEO John Simard commented, “We are thrilled to have Dr. Simpson present these findings at the AAD tomorrow. We expect these results to enable the advancement of a new and very important treatment for what is a rather under appreciated disease in terms of its severity and wide-spread impact on the lives of people around the world.”

In the study, 38 patients in two treatment groups received a low (200mg) or high (400mg) dose of bermekimab once weekly for either a 4 or 7-week treatment regimen, respectively. There was statistically and clinically significant improvement in treatment response for key measures of disease severity in the high dose versus the low dose group.

About True Human™ Therapeutic Antibodies

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.

Cautionary Note on Forward-Looking Statements

This press release contains forward-looking statements, including declarations regarding management's beliefs and expectations that involve substantial risks and uncertainties. In some cases, you can identify forward-looking statements by terminology such as "may," "will," "should," "would," "could," "expects," "plans," "contemplate," "anticipates," "believes," "estimates," "predicts," "projects," "intend" or "continue" or the negative of such terms or other comparable terminology, although not all forward-looking statements contain these identifying words. Forward-looking statements are subject to inherent risks and uncertainties in predicting future results and conditions that could cause the actual results to differ materially from those projected in these forward-looking statements. These risks and uncertainties are subject to the disclosures set forth in the "Risk Factors" section of certain of our SEC filings. Forward-looking statements are not guarantees of future performance, and our actual results of operations, financial condition and liquidity, and the development of the industry in which we operate, may differ materially from the forward-looking statements contained in this press release. Any forward-looking statements that we make in this press release speak only as of the date of this press release. We assume no obligation to update our forward-looking statements whether as a result of new information, future events or otherwise, after the date of this press release.

Contact
Ashley Otero
aotero@xbiotech.com
512-386-2930