XBiotech Publishes Results in PLOS ONE for its True Human Antibody 514G3 Targeting S. aureus

Report Documents 514G3's Ability to Protect Mice Against Deadly S. aureus Bacteremia Infections

AUSTIN, Texas, Jan. 25, 2018 (GLOBE NEWSWIRE) -- XBiotech Inc. (NASDAQ:XBIT) announced today the publication of "A Natural Human Monoclonal Antibody Targeting Staphylococcus Protein A Protects Against Staphylococcus aureus (S. aureus) Bacteremia ." in the journal PLOS ONE. The article reports on research involving the Company's therapeutic monoclonal antibody, 514G3, and its ability to neutralize a key immune evasion mechanism of S. aureus involved in the establishment of serious or even deadly infections. The 514G3 antibody was a naturally occurring antibody derived from a healthy individual with highly targeted immunity against S. aureus capable of neutralizing all strains of the bacteria, including a drug-resistant or so-called MRSA form.

"Continued emergence of multi drug resistant strains of S. aureus along with increased aging and immunocompromised populations, contribute to a need for new solutions to this deadly infection," commented Dr. Sushma Shivaswamy, Ph.D., XBiotech's Chief Scientific Officer. She further stated, "The present study confirms the mechanism of action of 514G3, and its ability to neutralize and kill the bacteria in a strain-independent manner."

The Company has previously announced top-line results from a Phase I/II clinical study, which reported a reduction in adverse events and shorter hospitalization associated with the 514G3 therapy, even with 514G3-treated patients tending to be sicker than those receiving placebo. The U.S. FDA has recognized the potential of this treatment, designating this as a Fast Track development program.

About True Human(TM) Therapeutic Antibodies
XBiotech's True Human(TM) 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(TM) 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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Contact
Ashley Otero
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