Optimization and clinical validation of dual-target RT-LAMP for SARS-CoV-2

•The LAMP method performs equally to international reference RT-PCR methods for detection of SARS-CoV-2.•Experiments have been conducted that fulfil regulatory criteria by international bodies.•LAMP as an LDT does not rely on RT-PCR reagents and does not cannibalize key reagents and kits in those supply chains.•The test is rapid with a result in less than 30 min after extraction.•Many countries can use this LDT option internationally in one or other format and provide vital testing.•Potential to apply this chemistry to a point of care method exists. A novel reverse-transcriptase loop mediated amplification (RT-LAMP) method targeting genes encoding the Spike (S) protein and RNA-dependent RNA polymerase (RdRP) of SARS-CoV-2 has been developed. The LAMP assay achieves a comparable limit of detection (25–50 copies per reaction) to commonly used RT-PCR protocols using clinical samples quantified by digital droplet PCR. Precision, cross-reactivity, inclusivity, and limit of detection studies were performed according to regulatory standards. Clinical validation of dual-target RT-LAMP (S and RdRP gene) achieved a PPA of 98.48 % (95 % CI 91.84%–99.96%) and NPA 100.00 % (95 % CI 93.84%–100.00%) based on the E gene and N2 gene reference RT-PCR methods. The method has implications for development of point of care technology using isothermal amplification.