Delafloxacin, the most recently approved fluoroquinolone, is the most broad-spectrum fluoroquinolone with activity against Gram-negative bacteria including Pseudomonas aeruginosa Gram-positive bacteria including MRSA, as well as atypical respiratory tract pathogens Anaerobes As fluoroquinolone use has increased, resistance, particularly to older fluoroquinolones, is developing among Enterobacterales, P aeruginosa, S pneumoniae, and Neisseria species.