Establishment of an in vivo -based assay using a silkworm infection model for phenotypic evaluation of antimicrobial drug combinations against Mycobacterium abscessus

Mycobacterium abscessus exhibits high intrinsic drug resistance, requiring combination therapy. We developed a silkworm ( Bombyx mori ) infection model as a whole-organism, in vivo -based platform for quantitative, outcome-based evaluations of antimicrobial combinations. The system, examined using clarithromycin-amikacin and imipenem-cefoxitin combinations, showed interaction profiles that were qualitatively consistent with those observed in vitro . This rapid, reproducible, and ethical assay enables reliable phenotypic assessments of synergistic or antagonistic effects and may facilitate the evaluation and prioritization of antimicrobial combination regimens in preclinical studies.