Detecting COVID-19 using only a smartphone

92% sensitivity for detecting COVID-19 with a new cough audio-based algorithm

BRISBANE,Australia,March 22,2022 -- ResApp Health Limited (ASX:RAP) today announced positive results for a new novel cough audio-based COVID-19 screening test that only requires a smartphone. In an exploratory clinical trial of 741 patients (446 COVID-19 positive) recruited in the United States and India,ResApp's screening test,which uses machine learning to analyse the sound of a patient's cough,was found to correctly detect COVID-19 in 92% of people with the infection.

ResApp will position this as a non-invasive,instant,smartphone only screening test to rule out COVID-19 and be used prior to a rapid antigen (RAT) or PCR test.

In the trial,the test achieved a sensitivity of 92% (better than real-world data on rapid antigen tests[i],[ii]) and a specificity of 80%. The combination of high sensitivity and 80% specificity results in 8 out of 10 people without COVID-19 being correctly screened as negative and not requiring a follow-on rapid antigen or PCR test.

The performance of the algorithm was obtained using K-fold cross-validation to provide an estimate of performance on unseen data. ResApp intends to submit the results for publication in a peer-reviewed journal in the coming weeks.

As a smartphone-based test,it's non-invasive,easy-to-use,and instant,the entire test and results takes less than 30 seconds. The test also has unlimited scalability,no supply chain or distribution issues and none of the environmental impacts of rapid antigen tests.

ResApp will target use in settings where frequent COVID-19 testing is required,such as employee,healthcare worker and student screening,travel,sports,entertainment,and aged care.

Professor Catherine Bennett,Chair of Epidemiology at Deakin University,and a member of ResApp's COVID-19 Scientific Advisory Boardsaid: "The scale of this pandemic and the likely evolution to an endemic disease means we need more scalable diagnostic tools that can balance our current over-reliance on rapid antigen and PCR tests. By rapidly ruling out COVID-19,ResApp's COVID-19 test would significantly reduce the number of rapid antigen and PCR tests required,while still maintaining the disease surveillance needed to manage the continued impact of COVID-19. The simplicity,ease of use and unlimited scalability of ResApp's test will be welcomed by public health officials around the world."

Tony Keating,CEO and Managing Director of ResAppadded: "This non-invasive,smartphone test will offer a unique opportunity to provide a rule-out screening test for COVID-19 at scale across the world,delivering huge savings to government,insurers and the public as well as significantly reducing the environmental impact of rapid antigen and PCR tests. These results also build our confidence in the development of patient management and monitoring tools for COVID-19 and expanding our research into long-COVID."

[i]Dinnes J.,et al. (2021). Rapid,point-of-care antigen and molecular-based tests for diagnosis of SARS-CoV-2 infection. Cochrane Database of Systematic Reviews. https://doi.org/10.1002/14651858.CD013705.pub2

[ii]Hayer J.,Kasapic D. and Zemmrich,C. (2021). Real-world clinical performance of commercial SARS-CoV-2 rapid antigen tests in suspected COVID-19: A systematic meta-analysis of available data as of November 20,2020. International Journal of Infectious Diseases,108,592-602. https://doi.org/10.1016/j.ijid.2021.05.029

About ResApp Health Limited

ResApp Health Limited (ASX: RAP) is a leading digital health company developing smartphone applications for the diagnosis and management of respiratory disease with products that are CE Marked in Europe and TGA approved in Australia. For more information,visit www.resapphealth.com.au.