Exagen, Inc. is a commercial-stage diagnostics company, which engages in transforming the care continuum for patients suffering from debilitating and chronic autoimmune diseases by enabling timely differential diagnosis and optimizing therapeutic intervention. The company is headquartered in Vista, California and currently employs 199 full-time employees. The company went IPO on 2019-09-19. The firm offers physicians testing and healthcare providers in the diagnosis, prognosis, and management of autoimmune conditions. The firm develops and commercializes testing products under its AVISE brand. Its products include AVISE CTD, AVISE Lupus, AVISE APS, AVISE Vasculitis AAV, AVISE SLE Prognostic, AVISE Anti-CarP, AVISE PC4d, AVISE SLE Monitor, AVISE MTX and AVISE HCQ. Its lead testing product, AVISE CTD, enables differential diagnosis for patients presenting with symptoms indicative of a variety of connective tissue diseases (CTD) and other related diseases with overlapping symptoms. Its AVISE brand allows for the differential diagnosis, prognosis and monitoring of complex autoimmune and autoimmune-related diseases, including systemic lupus erythematosus (SLE) and rheumatoid arthritis. Its product portfolio integrates CB-CAPs technology, which is a stable and reliable method for differentially diagnosing SLE.