TABLE 5.

Analysis of QRDR mutations in S. aureus isolates from the delafloxacin arm of the clinical study resistant to levofloxacin and/or ciprofloxacin and the corresponding microbiological response^a

No. of isolates	QRDR mutation profile				No. of patients with an ME microbiological response at follow-up/total no. evaluated (% eradicatedb)	MIC (μg/ml)
						Delafloxacin			Levofloxacin			Ciprofloxacin
	gyrA	gyrB	parC	parE		Range	50%	90%	Range	50%	90%	Range	50%	90%
1	E88K S84L	WT	E84G S80Y	WT	1/1 (100)	4			>8			>8
69c	S84L	WT	S80Y	WT	68/69 (98.6)	0.12–0.25	0.12	0.25	4 to 8	4	8	8 to >8	8	>8
5d	S84L	WT	S80F	WT	4/5 (80)	0.25–0.5			8 to >8			>8
3	S84L	WT	S80Y	P451S	3/3 (100)	0.25–0.5			>8			>8
1	S84L S85P	WT	S80F	D432N	1/1 (100)	0.5			>8			>8
3	S85P	WT	S80F	WT	3/3 (100)	0.03			2			8
1d	S84L	WT	S80F S80Y	WT	0/1 (0)	0.25			8			>8
1	WT	WT	S80F	WT	1/1 (100)	0.015			1			4

^aResults are from pooled data for the MEFUI population. ME, microbiologically evaluable; MEFUI, microbiologically evaluable at follow-up for the investigator-assessed response; MIC₅₀, lowest MIC that inhibits 50% of the strains (≥10 strains) of a single species; MIC₉₀, lowest MIC that inhibits 90% of the strains (≥10 strains) of a single species; QRDR, quinolone resistance-determining region; WT, wild type.

^bDocumented or presumed eradicated.

^cFor one subject, a follow-up isolate was obtained, and this isolate was unrelated to the baseline isolate, as determined using pulsed-field gel electrophoresis. Only one of these isolates is counted in Table 6.

^dFor one subject, the subject had one isolate from blood and one from skin with different QRDR mutations with the same MIC value. Both isolates are counted in Table 5 but only one of these isolates is counted in Table 6.