Exagen’s AVISE® MTX Test Supports Horizon Therapeutics Clinical Trial to Evaluate Pegloticase with Methotrexate to Enhance Response Rates for People Living with Uncontrolled Gout

New study using Exagen’s test will enroll 135 subjects

SAN DIEGO, Oct. 24, 2019 (GLOBE NEWSWIRE) — Exagen Inc. (Nasdaq: XGN), is pleased to announce clinical study support for Horizon Therapeutics plc (Nasdaq: HZNP) to measure methotrexate polyglutamates (MTXPGs), the active metabolites of methotrexate (MTX) in the MIRROR Randomized Controlled Trial (RCT) Study. This study, Methotrexate to Increase Response Rates in Patients with Uncontrolled GOut Receiving pegloticase, will enroll approximately 135 subjects to evaluate the use of methotrexate as an immunomodulator to meaningfully attenuate an immune response to pegloticase in adults living with uncontrolled gout. Many biologics have an improved response rate when they are administered together with methotrexate, which reduces the formation of anti-drug antibodies.

Ron Rocca, Chief Executive Officer at Exagen stated, “This agreement adds to our initiative to build strong alliances with significant pharmaceutical organizations that are developing therapeutics with a profound impact on disease. Every day information from our testing is being used by physicians to aid in the diagnosis, prognosis and monitoring of patients suffering from inflammatory and autoimmune diseases and AVISE MTX, with its easy AVISE Touch finger stick collection method, is just one of ways we help doctors optimize patient care. By utilizing our state-of-the-art laboratory and patented AVISE tests to support trials and product development, we are advancing our commitment to be patient focused and discovery driven.”

About Exagen Inc.

Exagen is dedicated to transforming the care continuum for patients suffering from debilitating and chronic autoimmune diseases by enabling timely differential diagnosis and optimizing therapeutic intervention. Exagen has developed and is commercializing a portfolio of innovative testing products under its AVISE brand, several of which are based on our proprietary Cell-Bound Complement Activation Products, or CB-CAPs, technology. Exagen’s goal is to enable rheumatologists to improve care for patients through the differential diagnosis, prognosis and monitoring of complex autoimmune and autoimmune-related diseases, including SLE and rheumatoid arthritis. Exagen’s laboratory testing facility is CAP accredited, CLIA certified.

Forward-Looking Statements

Exagen cautions you that statements in this press release that are not a description of historical facts are forward-looking statements. These statements are based on the Company’s current beliefs and expectations. Such forward-looking statements include, but are not limited to, statements regarding the results of these clinical utility studies validating the AVISE MTX test and the potential to lead to increased adoption of the AVISE MTX test. The inclusion of forward-looking statements should not be regarded as a representation by Exagen that any of its plans will be achieved. Actual results may differ from those set forth in this press release due to the risks and uncertainties inherent in Exagen’s business, including, without limitation: Exagen’s commercial success depends upon attaining and maintaining significant market acceptance of its testing products and promoted therapeutics among rheumatologists, patients, third-party payers and others in the medical community; if third-party payers do not provide coverage and adequate reimbursement for Exagen’s testing products, or they breach, rescind or modify their contracts or reimbursement policies or delay payments for its testing products or promoted therapeutics, or if Exagen or its partners are unable to successfully negotiate payer contracts, Exagen’s commercial success could be compromised; and other risks described in the Company’s prior press releases and in the Company’s filings with the Securities and Exchange Commission, including under the heading “Risk Factors” in the Company’s Registration Statement on Form S-1 and any subsequent filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and we undertake no obligation to revise or update this press release to reflect events or circumstances after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995.