ASAK-22

ASAK-22 is a preclinical **antibody-antibiotic conjugate** designed to eradicate intracellular *Staphylococcus aureus*, especially methicillin-resistant *S. aureus* (MRSA). It consists of an anti-*S. aureus* antibody conjugated through a valine-alanine dipeptide linker to the antibiotic payload KRM-1657. The intended mechanism is targeted binding to *S. aureus*, cellular uptake of the conjugate into infected host cells, intracellular linker cleavage, and release of KRM-1657 to kill intracellular bacteria that are poorly cleared by standard extracellularly active antibiotics such as vancomycin. Publicly available evidence for ASAK-22 currently appears limited to a 2024 peer-reviewed preclinical publication reporting in vitro activity against intracellular MRSA and reduced bacterial burden in a mouse bacteremia model after a single administration.