Coccidioidomycosis is a serious form of fungal pneumonia that predominantly affects people who visit or live in the southwest United States and northern Mexico. Within the endemic zone, it can be extremely common. Current diagnostics for coccidioidomycosis include fungal culture, microscopy, and serology (detection of patient antibodies). These tests have limitations that include cost, time to result, and limited sensitivity. They also all require specialized equipment and user expertise. Consequently, most patients experience long delays (>3 weeks) prior to receiving an accurate diagnosis. These diagnostic challenges and delays result in poor patient care, poor antimicrobial stewardship, and increased healthcare costs.
DxDiscovery’s proposed solution is to produce a coccidioidomycosis antigen-detection immunoassay that is rapid, inexpensive, and usable at or near the point of care. The approach is detection of Coccidioides cell wall polysaccharides from minimally invasive specimens, such as urine or serum. To address different end user needs across the spectrum of health care workers who encounter coccidioidomycosis patients, we are developing both a kit-based ELISA, which could be easily used in most hospital laboratories, and a lateral flow immunoassay (like the at-home COVID-19 test), which could be deployed by front-line clinicians directly at the point-of-care (e.g. urgent care centers and primary care clinics). Both options would increase test accessibility and provide actionable diagnostic information without the need to ship specimens to a reference laboratory. The goal is to enable prompt diagnosis of coccidioidomycosis and the swift initiation of appropriate patient care.
In Phase I of this project, which was funded by a small business innovation research (SBIR) contract from the National Institute of Allergy and Infectious Disease (NIAID), DxDiscovery developed a library of monoclonal antibodies reactive with Coccidioides polysaccharides and incorporated them into a prototype immunoassay in the ELISA format. This newly-received SBIR Phase II contract funding from NIAID will support optimization of the diagnostic in both the antigen-capture ELISA and lateral flow immunoassay format as well as evaluation of the assay with archived patient specimens from clinical collaborators at the University of Arizona. Technical support in the form of Coccidioides fungal culture and fungal polysaccharide purification will be provided by both University of Arizona collaborators and additional collaborators at the University of Nevada, Reno.