In vitro, SQ641 was the most potent of the capuramycin analogues against all NTM tested, both laboratory and clinical strains.

Conjugation of capuramycin analogues with AUA or DEC enhanced in vitro activity, extended the spectrum of activity in Gram-positive bacteria and increased intracellular activity against H37Rv.

SQ109 and PNU combinations were additive and improved the rate of MTB killing over individual drugs. These data suggest that the drugs may work together cooperatively to eliminate MTB in vivo.