Delafloxacin is a next generation fluoroquinolone with a broad spectrum of activity. This compound is significantly more active than other quinolones against Gram-positive organisms, including potent activity against quinolone resistant Gram-positive bacteria and methicillin resistant Staphylococcus aureus (MRSA), while retaining the broad spectrum advantage expected from the quinolone class. Delafloxacin has been shown to be at least 16 fold more potent than levofloxacin, ciprofloxacin, gatifloxacin and moxifloxacin against ciprofloxacin resistant MRSA (MIC90 of ≤ 0.5 ug/ml for delafloxacin versus > 16 ug/ml for all other quinolones). Delafloxacin has also been shown to be more potent than existing quinolones against a range of Gram-positive, anaerobic and Gram-negative organisms. Both oral and intravenous formulations have been developed for this compound. Clinical development of delafloxacin includes twelve Phase 1 and three completed Phase 2 clinical trials involving more than 1,300 subjects. These studies have shown delafloxacin to be both clinically efficacious and safe. The oral formulation of delafloxacin has been shown to have no evidence of either phototoxicity or QTc prolongation in Phase 1 studies and has demonstrated efficacy in two Phase 2 clinical trials (community acquired pneumonia (CAP) and bronchitis when compared to levofloxicin). The IV formulation of delafloxacin has demonstrated efficacy in a recent Phase 2 clinical trial in complicated skin and skin structure infections (cSSSI) when compared to tigecycline.