Archon is a multiplex immunoassay clinical blood test that is used by primary care physicians to determine the risk that lung cancer is present in asymptomatic individuals from a high-risk population (20 pack/year smokers over the age of 50) to help deter- mine which patients need to be directed to appropriate noninvasive diagnostic followup (e.g. low-dose computed tomography (LDCT)). The National Lung Screening Trial (NLST) study  found that yearly LDCT scanning reduced lung cancer-specific and all-cause mortality in high-risk individuals by 20% and 6.7% respectively as compared to chest x-rays.
However, the false-positive rate of LDCT and x-ray screening is very high: 96.4% and 94.5% of lesions detected by LDCT and chest radiography turned out to be false positives and the typical patient will have a 24% chance of a suspicious finding after even a single LDCT scan. The sensitivity for LDCT and chest radiography was 93.8% and 73.4% respectively. It was determined that 320 individuals would need to be scanned with LDCT to prevent one lung cancer death . While the costs of a single LDCT are modest, follow-up testing of false positives is both invasive and expensive. Another major drawback of LDCT scanning is low patient compliance. Our interviews with primary care providers suggest that less than 1% of high-risk smokers are getting yearly scans 3 years after the results of the NLST were reported. Increased patient familiarity and improved reimbursement for LDCT are expected to increase this compliance rate only incrementally. For these reasons, a robust and cost-effective early-stage biomarker test using blood drawn in a primary care setting (at health fairs, mobile laboratories, etc.) is essential to both reduce the rate of unnecessary testing and to improve patient compliance. Thus, our annual blood test and conditional LDCT test function as a tandem screening paradigm to improve outcomes for patients with lung cancer.
Archon’s unique technical approach involves measuring two distinct types of analytes circulating in the blood: tumor antigens and autoantibodies, and combining the same with a proprietary algorithm to generate a score categorizing the risk that the patient has lung cancer. More specifically, we report here on a panel comprising three tumor antigens—CEA, CA125, and CYFRA and one autoantibody (NY-ESO1). The tumor antigens have individually and collectively been shown by dozens of outside investigators around the world to distinguish early lung cancer from risk-matched controls. The combination of “established” biomarkers with more innovative analytes such as autoantibodies coupled with advanced statistical treatment provides an optimal panel for screening diverse, asymptomatic patient populations.