Identification of antimicrobial activity among FDA-approved drugs for combating Mycobacterium abscessus and Mycobacterium chelonae

Methods: In this study, we screened 1040 FDA-approved drugs against M. abscessus and M. chelonae. Results: Of the drugs screened, 32 compounds exhibited significant antimicrobial activity, with an MIC ≤ 8m g/L, against M. chelonae, while only 7 compounds showed such activity against M. abscessus. Notably, neostigmine bromide and cinnarizine exhibited highly significant antimicrobial activity against M. chelonae, but had little potency against M. abscessus. Metronidazole and puromycin were the only drugs that acted equipotently against both strains, in decreasing order of effectiveness. Conclusions: The dearth of identified compounds active against M. abscessus exemplifies its ability to resist drugs as well as the resilience of rapidly growing NTM. Repurposing of approved drugs is a viable alternative to de novo drug discovery and development.