Natrunix-SQ, A True Human Antibody Therapy Discovered and Manufactured at XBiotech, Is Aimed as a Breakthrough Treatment for Arthritic DiseaseAUSTIN, Texas, Jan. 26, 2022 (GLOBE NEWSWIRE) — XBiotech Inc. (NASDAQ: XBIT) enrolled the first patient in a randomized, double-blind, placebo-controlled clinical study to evaluate safety and pharmacokinetics of Natrunix-SQ. Natrunix-SQ targets a crucial inflammatory pathway involved in pain and joint destruction in various forms of arthritis. XBiotech believes that Natrunix-SQ may be the most effective means of blocking the inflammatory pathway involved in arthritis and thus could represent a breakthrough treatment for arthritides. The Phase I study represents the launch of the clinical program for Natrunix-SQ for the treatment of rheumatological diseases. The Phase I study will evaluate Natrunix-SQ blood levels in the context of increasing doses. These findings will guide follow-up studies with Natrunix-SQ. Upon successful completion of the Phase I study, multiple Phase II studies to evaluate Natrunix-SQ in rheumatology are planned. Natrunix-SQ is an antibody derived from a human donor where it was acting to naturally neutralize inflammation. Natrunix-SQ binds and neutralizes the action of one of the most potent inflammation-causing substances known to be produced by the body—interleukin-1. The body’s production of interleukin-1 has for decades been viewed as a key target for treating inflammatory disease. To date, therapies that block interleukin-1 have been successfully developed and marketed. However, no therapy to date has been developed that neutralizes interleukin-1 like Natrunix-SQ. Interleukin-1 is made up of two distinct components: IL-1a and IL-1b. Natrunix-SQ is the first therapeutic to directly and specifically target and neutralize the activity of IL-1a. In recent years, world-class research has shown that IL-1 a may in many cases be the crucial target in blocking the disease-causing activities of interleukin-1. The unique approach of Natrunix-SQ to blocking interleukin-1-driven inflammation holds promise as a new generation of anti-inflammatory therapy in arthritis. As a naturally derived human antibody, it is also by design expected to be among the safest and best tolerated medicines possible. Natrunix-SQ was discovered and developed by XBiotech researchers in Austin, Texas. XBiotech also produces the drug product and manufactures the completed pre-filled syringes at its operation in Austin. XBiotech has the manufacturing capability to produce drug product used for the clinical programs and for commercialization of the candidate therapy for arthritis. 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. 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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 Wenyi Weiwwei@xbiotech.comTel. 512-386-2934