Meeting the cost and privacy demands for detecting Anabolic Androgenic Steroid doping in youth athletics with rationally designed nuclear receptor BioAssays - Project Summary This SBIR project concerns the validation of a novel measurement platform to identify persons, particularly youths, using testosterone and testosterone-like drugs. These Anabolic Androgenic Steroids (AASs) are Schedule III controlled substances with high rates of unsupervised, illicit use. In the US, AAS use by the general public has a lifetime prevalence of 6.4% for males and 1.6% for females. AASs are referred to as Appearance and Performance Enhancing Drugs (APEDs) for their perceived benefits to physical appearance and/or athletic prowess. Media attention has focused on elite athletes caught ‘doping’ by national anti-doping monitors. Less publicized is the 1.3% of US grade 12 males, including unmonitored youth athletes, who in 2022 reported AAS abuse within 30 days of being surveyed. There are technical, sample collection/shipping and cost impediments that prevent testing of pay-to-play amateur athletes using the urine-focused methods developed for elite athletes. XCellAssay developed an amateur-compatible method in which a high throughput Androgen Receptor (AR) BioAssay quantifies the levels of all androgens in just µl’s of blood, dried on a filter paper and added to a micro-well in a 384-well plate. XCellAssay’s proprietary Internal Control Receptor (ICR), measured in the same well, detects intermediates of the steroid synthesis pathway that decrease when doped steroids activate negative feedback controlling steroid homeostasis. This study is designed to show if the expected decrease in ICR ‘intermediate steroids’, relative to AR ‘androgens’, is sufficient to reliably identify individuals receiving supplemental androgens. In preliminary studies, the ICR/AR measurement ratio was consistent in 12 sera from presumably ‘clean’ adult males over the full natural range in androgen concentration. In the proposed Phase I project, large numbers of deidentified blood samples will be obtained from commercial biobanks for an appropriately powered study of: Aim 1 the natural age- and gender-specific variations in ‘normal’ ICR/AR BioAssay activity ratios and Aim 2, whether clinical testosterone supplementation reliably reduces ICR/AR measurement below the lower margin of ‘normal’. The reliability in ICR/AR detection of ‘doping’ in blood will be assessed also by direct comparison to matched urine samples measured using the currently established ‘doping’ detection protocols. The Phase I Specific Aims will rapidly validate, or not, the performance of the ICR/AR BioAssay ratio as a doping detection tool. If Phase I milestones are attained, Phase II would develop the final collection kit and would broadly compare the ICR/AR and the current doping-detection protocols on blood/urine collected from random athletes, a low percentage of whom will have doped with any of a number of AASs. The goal is to define if the ICR/AR BioAssay can reliably detect androgen doping at the <$30/sample (collection/shipping/ measurement/ reporting) needed to be compatible with the cost and testing requirements for high-caliber, youth amateur athletics.