Bloodstream infection detection directly on whole blood Summary Bloodstream infection caused by yeast is a life-threatening condition that affects approximately 50,000 patients each year in the United States. Yeast bloodstream infection is a highly lethal infection associated with mortality rates greater than 40%. Early antifungal administration is crucial to improve the probability of patient survival. However, the current gold standard for the diagnosis of yeast bloodstream infection is blood culture (BC), which takes one to five days. To provide physicians with the needed diagnostic information to properly treat these patients, we are developing an automated platform for rapid, broad and cost-effective identification of yeast in whole blood without BC. The new platform is based on Single MOLecule Scanning (SMOLT), a novel sample preparation and molecular detection method developed at Scanogen. Here, we propose to complete the development of an automated instrument and the SMOLT- Yeast assay that will detect most yeast responsible for bloodstream infections directly on whole blood. We successfully completed or surpassed all Phase II milestones. The SMOLT-Yeast assay was developed, automated, and tested with clinical samples. To diagnose a patient, a vacutainer with the patient’s blood is inserted into a disposable cartridge and processed by a desktop instrument. The new assay demonstrated high analytical and clinical performance with limit of detection of 1 CFU/mL for 11 yeast species, an overall clinical sensitivity of 94.2% and an overall clinical specificity of 99.8%. In Phase IIB, we will address all the design improvements that are needed before the FDA pivotal studies. We will optimize the cartridge design to reduce manufacturing variability and cost, as well as to increase storage stability (Aim 1 and Aim 2). We will optimize the instrument design to improve its usability, increase its mechanical stability, and reduce its size (Aim 3). We will also conduct an in-hospital pilot study to test the assay and the approach that will be used for the pivotal studies (Aim 4). We have assembled the appropriate team to accomplish these tasks: assay development scientists that developed the SMOLT technology and experienced engineers, including the former Vice President of Engineering at Becton Dickinson. In addition, Scanogen has established a collaboration with a team from the Johns Hopkins University that will conduct the clinical evaluation and will provide feedback to ensure that the new system responds to the clinical needs. If successful, the new platform will significantly improve the outcome of patients with yeast bloodstream infection by providing rapid results and enabling timely initiation of proper antifungal treatment. Furthermore, the new platform will have a broader impact by enabling assays targeting other microorganisms that cause bloodstream infections.