XGN Exagen Inc

Exagen Inc. (Nasdaq: XGN), an organization dedicated to transforming the care continuum for patients suffering from autoimmune diseases, announced today that all AVISE test offerings (CTD, Lupus, SLE Prognostic, SLE Monitor, APS, Vasculitis AAV, MTX, and HCQ) are a contracted in-network service with St. Charles Health System, the largest provider of medical care in Central Oregon.

“St. Charles has a far-reaching impact on the health and wellbeing of the communities they serve. As the largest employer in the region, providing access to AVISE testing will play an important part in enabling rheumatologists to improve patient care through the differential diagnosis, prognosis and monitoring of complex autoimmune diseases, including SLE,” said Ron Rocca, President and CEO of Exagen.

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 providers to improve care for patients through the differential diagnosis, prognosis and monitoring of complex autoimmune and autoimmune related diseases, including rheumatoid arthritis and lupus. For further information please visit www.exagen.com.

About St. Charles Health System

Headquartered in Bend, OR, St. Charles Health System, Inc., owns and operates St. Charles Bend, Madras, Prineville and Redmond. It also owns family care clinics in Bend, La Pine, Madras, Prineville, Redmond and Sisters. St. Charles is a private, not-for-profit Oregon corporation and is the largest employer in Central Oregon with more than 4,500 caregivers. In addition, there are more than 350 active medical staff members and nearly 200 visiting medical staff members who partner with the health system to provide a wide range of care and service to our communities.

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 expected benefits of the positive medical policy coverage for the AVISE test offerings with St. Charles Health System, including the availability and expected use of the AVISE test offerings through the St. Charles Health System network, and any potential for increased use of the AVISE laboratory tests. 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: the COVID-19 pandemic may continue to adversely affect our business, financial condition and results of operations, including as a result of shutdowns of our facilities and operations as well as those of our suppliers and courier services, impeding patient movement and interruptions to healthcare services causing a decrease in test volumes, disruptions to the supply chain of material needed for our tests, our sales and commercialization activities and our ability to receive specimens and perform or deliver the results from our tests, delays in reimbursement and coverage decisions from Medicare and third-party payors and in interactions with regulatory authorities, and delays in ongoing and planned clinical trials involving our tests; the company’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; the company’s ability to successfully execute on its Dx/Rx strategy, including its promotion efforts for SIMPONI®; third party payers not providing coverage and adequate reimbursement for the company’s testing products or promoted therapeutics; the company’s ability to obtain and maintain intellectual property protection for its testing products; regulatory developments affecting the company’s business; and other risks described in the company’s prior press releases and the Company’s filings with the Securities and Exchange Commission (SEC), including under the heading “Risk Factors” in the company’s Annual Report on Form 10-K 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 Exagen undertakes no obligation to update such statements to reflect events that occur or circumstances that exist 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.

InvestorsWestwicke PartnersMike CavanaughMike.Cavanaugh@westwicke.com 646.677.1838

CompanyExagen Inc.Kamal Adawi, Chief Financial Officerkadawi@exagen.com 760.477.5514