Part I.
Forward-Looking Statements and Market Data
This Annual Report on Form 10-K, or this Annual Report, contains forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. All statements other than statements of historical facts contained in this Annual Report, including statements regarding our future results of operations and financial position, business strategy, current and future product offerings, reimbursement and coverage, our ability to implement an integrated testing with therapeutics strategy, the expected benefits from our partnership or promotion arrangements with third parties, research and development costs, timing and likelihood of success and plans and objectives of management for future operations, are forward-looking statements. These statements involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. This Annual Report also contains estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.
In some cases, you can identify forward-looking statements by terms such as "believe," "may," "will," "should," "predict," "goal," "strategy," "potentially," "estimate," "continue," "anticipate," "intend," "could," "would," "project," "plan," "expect," "seek," and similar expressions that convey uncertainty of future events or outcomes, are intended to identify forward-looking statements.
The forward-looking statements in this Annual Report are only predictions. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our business, financial condition and results of operations. These forward-looking statements speak only as of the date of this Annual Report and are subject to a number of risks, uncertainties and assumptions described under the sections “Risk Factors” and elsewhere in this Annual Report. Because forward-looking statements are inherently subject to risks and uncertainties, some of which cannot be predicted or quantified and some of which are beyond our control, you should not rely on these forward-looking statements as predictions of future events. The events and circumstances reflected in our forward-looking statements may not be achieved or occur and actual results could differ materially from those projected in the forward-looking statements. Moreover, we operate in an evolving environment. New risk factors and uncertainties may emerge from time to time, and it is not possible for management to predict all risk factors and uncertainties. Except as required by applicable law, we undertake no obligation to publicly update or revise any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise.
We use our trademarks in this Annual Report as well as trademarks, tradenames and service marks that are the property of other organizations. Solely for convenience, certain trademarks and tradenames referred to in this Annual Report appear without the ® and ™ symbols, but those references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or that the applicable owner will not assert its rights, to these trademarks and tradenames.
Item 1. Business
Company Overview
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. We have developed and are commercializing a portfolio of innovative testing products under our AVISE® brand, several of which are based on our proprietary Cell-Bound Complement Activation Products, or CB-CAPs, technology. CB-CAPs assess the activation of the complement system, a biological pathway that is widely implicated across many autoimmune and autoimmune-related diseases, including systemic lupus erythematosus, or SLE. Our 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, or RA. Our strategy includes leveraging our portfolio of testing products to market therapeutics through our sales channel, targeting the approximately 5,000 rheumatologists across the United States. Our business model of integrating testing products and therapeutics positions us to offer targeted solutions to rheumatologists and, ultimately, better serve patients.
We currently market nine testing products under our AVISE® brand, which we are leveraging to establish partnerships with leading pharmaceutical companies. In December 2018, we entered into a co-promotion agreement with Janssen Biotech, Inc., or the Janssen agreement, to exclusively promote SIMPONI® (golimumab), a subcutaneous, once-per-month, anti-tumor necrosis factor, or anti-TNF, biologic prescribed in combination with methotrexate, in the United States for the treatment of adult patients with moderate to severe RA and for other indicated rheumatic diseases. Combined U.S. sales of SIMPONI® and SIMPONI ARIA®, an intravenous formulation, were approximately $1.2 billion in 2019, of which we estimate approximately 50% was from sales of SIMPONI®. We began direct promotion of SIMPONI® in January 2019 and expanded our salesforce from 31 representatives as of December 31, 2018 to 50 representatives as of December 31, 2019 to support these promotion efforts. Unlike many diagnostic salesforces that are trained only to understand the comparative benefits of their tests, the specialized backgrounds of our salesforce coupled with our comprehensive training enables our sales representatives to interpret results from our de-identified patient test reports and provide unique insights in a highly tailored discussion with rheumatologists. We therefore believe our strategy of integrating the promotion of testing products and therapeutics uniquely positions us to expand SIMPONI®’s U.S. market share. Our SIMPONI® promotion efforts contributed approximately $1.5 million in incremental revenue in 2019 with our quarterly tiered promotion fee based on the incremental increase in total prescribed units above a predetermined average baseline of approximately 29,000 prescribed units per quarter.
We believe our strategy of integrating the promotion of testing products and therapeutics differentiates us from other diagnostic and pharmaceutical companies, and provides our specialized salesforce greater access to rheumatologists. Our integrated testing and therapeutics strategy results in a unique opportunity to promote targeted therapies in patient focused sales calls with rheumatologists, including those with whom we have a longstanding relationship and who have a history using our portfolio of testing products.
Our lead testing product, AVISE® CTD, enables differential diagnosis for patients presenting with symptoms indicative of a wide variety of connective tissue diseases, or CTDs, and other related diseases with overlapping symptoms. The comprehensive nature of AVISE® CTD allows for the testing of a number of relevant biomarkers in one convenient blood draw, as opposed to testing serially for individual biomarkers, which adds time and cost to the diagnostic process. We believe AVISE® CTD may provide clinical utility for over 23 million patients in the United States suffering from these diseases, which include SLE, RA, Sjögren’s syndrome, antiphospholipid syndrome, or APS, other autoimmune-related diseases such as autoimmune thyroid, and other disorders that mimic these diseases, such as fibromyalgia. There is an unmet need for rheumatologists to add clarity in their CTD clinical evaluation, and we believe there is a significant opportunity for our tests that enable the differential diagnosis of these diseases, particularly for potentially life-threatening diseases such as SLE.
We have demonstrated a strong track record of developing innovative testing products that meet the needs of diagnosing, prognosing and monitoring CTDs, as illustrated below:
AVISE® CTD leverages our proprietary CB-CAPs technology to enable the differential diagnosis SLE. AVISE® CTD provides rheumatologists and their patients with sensitive and specific results that allow for potentially faster and more accurate differential diagnosis of SLE as compared to other currently-marketed testing methods. Beyond SLE, AVISE® CTD allows rheumatologists to accurately diagnose other overlapping autoimmune and autoimmune-related diseases, including RA, with the same blood sample.
Our AVISE® SLE Monitor testing product also leverages our proprietary CB-CAPs technology by measuring two CB-CAPs biomarkers that offer insight into a patient’s disease activity. This test is designed to enable rheumatologists to effectively assess and optimize therapeutic intervention in patients diagnosed with SLE. Depending on disease severity, AVISE® SLE Monitor may be utilized by patients multiple times a year throughout their lives.
Our RA-focused testing products include AVISE® MTX and AVISE® Anti-CarP. AVISE® MTX is a drug monitoring test designed to aid in the optimization of methotrexate therapy, the standard of care and first-line therapy for patients with RA. AVISE® MTX is based on our proprietary methotrexate polyglutamate, or MTXPG, technology that measures blood levels of MTXPGs, the active metabolite of methotrexate linked to disease control in RA patients. Measuring MTXPGs allows rheumatologists to identify patients presenting with inadequate exposure to methotrexate enabling them to optimize dosing and achieve therapeutic levels commensurate with adequate disease control. AVISE® MTX is compatible with AVISE® Touch, our low-volume test sample collection method that allows for a micro-volume blood sample to be collected anywhere from a simple fingerstick. AVISE® Anti-CarP, which measures anti-carbamylated protein antibody, or anti-CarP, was developed by the Leiden University Medical Center, and we introduced it as a biomarker-driven RA prognostic test through a distribution agreement with Inova Diagnostics, Inc. with the goal of identifying patients prone to more severe disease.
We market our AVISE® testing products using our specialized salesforce. Since the launch of AVISE® CTD in 2012 through December 31, 2019, we have delivered over 387,000 of these tests, representing a compound annual growth rate of 81%, with limited incremental investment in our commercial infrastructure. Over 105,000 AVISE® CTD tests were delivered in 2019, representing 26% growth over 2018, and the number of ordering healthcare providers in the fourth quarter of 2019 reached 1,707, representing 34% growth over the same period in 2018. In the fourth quarter of 2019, we reached 572 adopting healthcare providers, which we classify as those who had previously prescribed at least 11 diagnostic tests in the corresponding period, compared to 506 in the same period in 2018. A high percentage of adopting healthcare providers continue to order tests in subsequent quarters, including a retention rate of approximately 98% among adopting healthcare providers in the fourth quarter of 2019.
In addition, we continue to populate a growing proprietary database of over 384,000 de-identified patient test results. We believe the insight emerging from these results has the potential to unlock value for pharmaceutical and biotechnology companies in the commercialization of therapeutics. We believe we also have the ability to further
leverage our database to optimize patient selection in clinical trials for companies developing therapeutics for autoimmune and autoimmune-related diseases. We plan to collaborate with our existing and future pharmaceutical and biotechnology partners to help maximize the full value of our in-house database.