Here are 1-3 brief analogies to describe Exagen:

• Exagen is like the Exact Sciences for autoimmune disease diagnosis and monitoring.
• Exagen is like Invitae, but focused on advanced diagnostic and monitoring tests for autoimmune conditions instead of genetic ones.
• Exagen is like Foundation Medicine, but applying advanced diagnostics to autoimmune diseases rather than cancer genomics.

• AVISE CTD: A lead diagnostic test for differentiating various connective tissue diseases.
• AVISE Lupus: A test that quantifies C4d levels to measure complement system activation in lupus patients.
• AVISE APS: A panel of autoantibody tests used to diagnose and manage Antiphospholipid Syndrome.
• AVISE SLE Prognostic: A panel of autoantibodies for assessing the risk of kidney, brain, and cardiovascular complications in SLE.
• AVISE Vasculitis AAV: A testing panel for the assessment and monitoring of anti-neutrophil cytoplasmic antibody associated vasculitis.
• AVISE Anti-CarP test: A test to identify Rheumatoid Arthritis patients with severe disease.
• AVISE PC4d: A test designed to measure platelet-bound C4d.
• AVISE SLE Monitor: A biomarker blood test used for monitoring systemic lupus erythematosus.
• AVISE MTX: A patented and validated blood test.
• AVISE HCQ: A blood test designed to monitor levels of hydroxychloroquine.

Exagen Inc. (XGN) sells its diagnostic testing products and services primarily to healthcare providers for the benefit of individual patients. The major categories of customers it serves are:

1. Rheumatologists: These are the primary medical specialists who utilize Exagen's AVISE brand diagnostic tests for the diagnosis, prognosis, and monitoring of autoimmune and autoimmune-related diseases in their patients. They are the prescribers and key decision-makers for ordering these tests.
2. Healthcare Facilities: This category includes clinics, hospitals, and medical groups that employ or host rheumatologists. These facilities are involved in the logistical ordering, processing, and billing for the diagnostic tests.
3. Patients with Autoimmune and Autoimmune-Related Diseases: While not directly purchasing in a retail sense, these individuals are the ultimate recipients and beneficiaries of Exagen's testing services. The tests aid in managing their conditions, such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA).

John Aballi, President & CEO

Mr. Aballi has served as President and CEO of Exagen since October 2022. He previously held the role of SVP, GM, Urology and CLIA COO for Veracyte, a molecular diagnostic company. In this role, he was responsible for expanding the urology franchise and managed Veracyte's CLIA laboratories. Prior to Veracyte, Mr. Aballi was a key member of the leadership team at Decipher Biosciences, a company specializing in genomic testing for prostate cancer, which was sold to Veracyte in March 2021 for $600 million. He also served as Head of Operations at Molecular Stethoscope and held various senior roles at Genoptix. Mr. Aballi was a Board Member of PFS Genomics, a molecular diagnostic company acquired by Exact Sciences in 2021.

Jeff Black, Chief Financial Officer

Mr. Black was appointed Chief Financial Officer in September 2024. He brings over 30 years of financial and accounting experience from numerous publicly traded companies. Prior to joining Exagen, he served as CFO of Standard BioTools, where he played a key role in its merger with SomaLogic. He was also CFO of Apollo Endosurgery, where he was instrumental in the company's turnaround and its subsequent $650 million sale to Boston Scientific. Earlier, he spent over four years as CFO of Alphatec Spine, where he managed significant financing transactions and acquisitions, contributing to the expansion of the company's market cap.

Dr. Michael Mahler, Chief Scientific Officer

Dr. Mahler was appointed Chief Scientific Officer in July 2025. He brings over two decades of leadership and innovation in autoimmune diagnostic research to Exagen. Throughout his career, Dr. Mahler has held senior scientific and leadership positions at various diagnostic companies, and his work has led to the discovery of novel autoantigens and the development of innovative diagnostic solutions. He previously served as Senior Vice President of Research Development and Business Development at Werfen. Dr. Mahler's scientific contributions include over 300 peer-reviewed publications and numerous patents in autoimmune disease diagnostics.

Dr. Tina S. Nova, Executive Chair of the Board

Dr. Nova was elected Executive Chair of the Exagen Board of Directors in January 2023. She has a distinguished career in the life science industry, having co-founded and served as President & CEO of Genoptix, which was acquired by Novartis AG for $470 million in 2011. She also served as President & CEO of Decipher Biosciences until its acquisition by Veracyte for $600 million in March 2021. Her previous leadership roles include CEO of Molecular Stethoscope and SVP & General Manager of Oncology at Illumina.

Dr. Prashanti Reddy, Medical & Laboratory Director

Dr. Reddy brings over 15 years of expertise in Flow Cytometry, Diagnostic Hematopathology, and Oncology to her role at Exagen. Her career includes leadership positions at Berkeley's Kaiser Permanente and Genoptix Medical Laboratories, where she made significant contributions to clinical practice and research. Dr. Reddy's work includes flow cytometry assay development to enhance diagnostic methodologies and contributions to digital pathology integration.

Key Risks to Exagen (XGN)

Exagen Inc. (XGN), a company specializing in diagnostic testing for autoimmune diseases, faces several significant risks that could impact its business operations and financial performance.

1. Reimbursement and Coverage Decisions: A primary risk for Exagen stems from potential delays in reimbursement and coverage decisions from Medicare and other third-party payors. Inadequate reimbursement and challenges in collecting funds for its diagnostic tests can significantly impact the company's financial viability and the market acceptance of its products. Exagen's commercial success heavily relies on attaining and maintaining significant market acceptance of its testing products among rheumatologists, patients, and third-party payors. Issues such as lost direct bill accounts and slower reimbursement for new biomarkers have already been identified as headwinds affecting average selling price (ASP) and gross margins.
2. Financial Health and Profitability: Exagen has demonstrated ongoing challenges with its financial health and profitability. The company has reported missing earnings per share (EPS) and revenue forecasts, along with increased net losses despite revenue growth. Declining cash reserves and a negative Altman Z-Score indicate potential financial distress and a risk of bankruptcy within the next two years. Operational inefficiencies impacting earnings, pressure on gross margins due to increased costs, and rising operating expenses further contribute to the company's profitability concerns.
3. Competition and Market Acceptance: The autoimmune diagnostic market is competitive, and Exagen's ability to maintain and grow its market share is crucial. The company's success depends on the widespread acceptance of its AVISE brand testing products by rheumatologists, patients, and the broader medical community. Competitive pressures and the need to sustain growth amid these pressures are ongoing challenges.

Addressable Markets for Exagen's Main Products and Services

• U.S. Autoimmune Disease Diagnostics Market: This market was estimated at approximately USD 2,337 million in 2025 and is projected to reach around USD 3,719 million by 2034. Another estimate places the U.S. autoimmune disease testing market size at USD 4.66 billion by 2030.
• North America Rheumatoid Arthritis (RA) Diagnostic Tests Market: The global market for RA diagnostic tests is estimated at USD 2.65 billion in 2025. North America is anticipated to hold a dominant position, accounting for 39.45% of this market in 2025, which translates to approximately USD 1.04 billion.
• North America Connective Tissue Disease (CTD) Diagnostics Market: The global connective tissue disease market, segmented by diagnosis (e.g., Antinuclear Antibody Test), was valued at USD 0.2676 billion (USD 267.6 million) in 2024. North America is reported to hold approximately 45% of this global market share, equating to roughly USD 120 million in 2024.

Here are 3-5 expected drivers of future revenue growth for Exagen (symbol: XGN) over the next 2-3 years:

1. Increased Testing Volume: Exagen experienced over 11% growth in testing volume in 2025 and anticipates high single-digit volume growth in 2026. This growth is driven by both the acquisition of new ordering physicians and increased utilization within existing accounts.
2. Growth in Average Selling Price (ASP): The company's trailing 12-month average selling price (ASP) for its tests increased by over 7% in 2025, and management projects low single-digit ASP growth for 2026. This improvement is expected to come from ongoing revenue cycle management execution and the increasing adoption of recently launched biomarkers.
3. Expansion of Sales Force and Market Presence: Exagen strategically expanded its sales force from 40 to 45 territories in 2025 and plans to add five more sales territories by the end of 2025. This expansion is a key strategy to drive increased testing volume and broader market penetration.
4. Launch of New Products and Biomarkers: Exagen has a strategic focus on product innovation, having launched three sets of innovative markers within an 18-month period and a total of seven new biomarkers in 2025. The company maintains a pipeline of five assets and aims to introduce one new product annually, including a myositis solution targeted for 2027, which is expected to expand its addressable market and contribute to revenue growth.
5. Growth in Pharma Services Business: The company's pharma services business generated $1.7 million in revenue in 2025, a significant increase from the previous year, and currently boasts a backlog of over $4 million. This emerging segment represents a new and growing revenue stream for Exagen.

Share Issuance

• In May 2025, Exagen priced an underwritten public offering of 3,350,000 shares of its common stock at $5.25 per share, with expected gross proceeds of $17,587,500.
• The company's issued and outstanding shares increased from 17,640,328 at December 31, 2024, to 22,911,575 at December 31, 2025.
• Exagen realized $26 million in net proceeds in 2025 from debt refinancing, a follow-on offering, and at-the-market (ATM) utilization.

Inbound Investments

• In 2025, Exagen raised capital through a $20 million public offering and a $25 million credit facility.
• The company's second quarter of 2025 saw a strengthened balance sheet with the closing of a $20.2 million public offering of common stock and a new loan credit facility.

Capital Expenditures

• Operating expenses for Exagen totaled $53 million in 2025, an increase of approximately 13% compared to 2024, with a primary focus on investments in commercial talent, territory expansion, and research and development (R&D).
• R&D expenses accounted for just over $6 million of operating expenses in 2025, representing a 16% increase, aimed at supporting the launch of seven new markers and ongoing pipeline development.
• Exagen operates an approximately 13,000 square foot laboratory in Vista, California, which is certified under CLIA and accredited by CAP. The company anticipates continued investment in R&D to develop additional testing products.