ABSTRACT The ongoing epidemic of sexually transmitted infections (STIs), particularly in men who have sex with men (MSM), is worsening as the fear of HIV and the acceptance/use of barrier methods (e.g condoms) decreases. STI diagnostics are the critical gateway to treatment, yet traditional test methods (i.e., mail-in kits and centralized labs) are decidedly ineffective for the individuals and groups most impacted by STIs, such as MSM, economically disadvantaged communities/countries, and those without health insurance. As stated by the WHO, “A major barrier to STI control and prevention is the unavailability of reliable, low-cost, point-of-care (POC) tests which allow diagnosis and treatment in a single visit.” Indeed, technology for POC STI tests that can be accessed at local clinics and performed by “lay health workers” during the patient visit are needed to address ongoing STI socioeconomic health disparities. Salus has invented 3STEP, a POC nucleic acid test (NAT) platform that addresses this critical need by enabling laboratory performance at the POC in a format that is as easy to perform as a rapid antigen test in <35 min using a single swab/sample. Laboratory performance in 3STEP is accomplished via exclusion-based sample preparation (ESP) for high-purity extraction/concentration (an often skipped but vitally important step in POC-NAT tests, particularly samples with more complex matrix such as anal swabs), while its POC simplicity and affordability is enabled by novel stabilized interface technology (SIFT). The single disposable device performs sample collection, nucleic acid extraction, and amplification/detection in spatially separated wells that enables rapid development of multiplexed test panels. Unlike many other POC NATs, there are no microfluidic valves, pumps, or electronics, minimizing costs, e-waste, and manufacturing complexity. Salus Discovery is now applying 3STEP to meet important POC STI testing needs. Specifically, in collaboration with Dr. Striker (MD, PhD) at the University of Wisconsin, we target a significant need/opportunity in the MSM population identified by the groundbreaking ANCHOR study for an anal HPV NAT to detect infections with high risk of anal cancer (no approved test is currently available for anal swabs). The multiplexing capability of 3STEP allows us to also target the need for lab-quality POC single-visit testing and treatment for the curable and highly prevalent STIs Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). We have preliminary data in the 3STEP platform with HPV 16, HPV 18, CT, and NG detection chemistries. Thus, in Aim 1 we will focus on optimizing and integrating the STI test chemistries into a panel and in Aim 2 we will use this panel to (i) efficiently assess the ability to detect each pathogen in actual patient samples, and (ii) compare different sampling methodologies (anal CT/NG swab vs. anal HPV cytology swab) setting the stage for a Phase II proposal.