In vitro Susceptibility of Nontuberculous Mycobacteria to Tedizolid

Figures & data

Table 1 The Drug Susceptibility Results of 7 Reference NTM Isolates

Organism	MICs of Tedizolid (mg/L)	MICs of Linezolid (mg/L)
M. abscessus ATCC 19977	4	32
M. fortuitum ATCC 6841	4	16
M. mucogenicum ATCC 49650	<0.125	<0.5
M. smegmatis ATCC 700084	0.5	1
M. peregrinum ATCC 700686	1	4
M. intracellulare ATCC 13950	16	64
M. kansasii ATCC 12478	0.5	2

Table 2 The Drug Susceptibility Results of 133 Clinical NTM Isolates

Organism	n	Antimicrobial Agent	MIC (mg/L)
			Range	MIC50	MIC90
RGM
M. abscessus complex	35	Tedizolid	0.125–8	2	4
		Linezolid	0.5–32	16	16
M. fortuitum	21	Tedizolid	0.25–8	4	8
		Linezolid	1–32	16	32
M. mucogenicum	4	Tedizolid	<0.125–0.5
		Linezolid	<0.5–2
M. chelonae	1	Tedizolid	0.5
		Linezolid	4
M. ltetiense	1	Tedizolid	4
		Linezolid	16
SGM
M. avium complex	40	Tedizolid	1 - >32	16	>32
		Linezolid	4 - >128	64	128
M. kansasii	18	Tedizolid	0.25–8	1	8
		Linezolid	2–64	8	32
M. marinum	10	Tedizolid	<0.125–2
		Linezolid	<0.5–16
M. virginiense	1	Tedizolid	4
		Linezolid	64
M. gordonae	2	Tedizolid	0.125–4
		Linezolid	4–16

Figure 1 MIC distributions of tedizolid for clinical isolates of (A) M. abscessus complex (n = 35), (B) M. fortuitum (n = 21), (C) M. avium complex (n = 40) and (D) M. kansasii (n = 18).

Table 3 FICIs of Tedizolid in Combination with Clarithromycin Against M. abscessus complex (n = 8)

Isolate ID	Subspecies	FICI		erm(41)
		TZD/Clarithromycin (Day 3)^a	TZD/Clarithromycin (Day 14)
ATCC 19977	M. abscessus	0.625	Induced resistant	Wildtype
18-T2394-2	M. massiliense	1	1.016	Truncated
18-T2449-2	M. massiliense	0.75	1.016	Truncated
BY1802	M. massiliense	1.016	1.016	Truncated
18-T1911	M. abscessus	0.625	1.016	Nonfunction T28C mutant
HS20072	M. abscessus	0.5	Induced resistant	Wildtype
HS19011	M. abscessus	0.5	Induced resistant	Wildtype
BY1803	M. abscessus	0.5	Induced resistant	Wildtype

Note: ^aBold style indicates synergy according to FIC.

Table 4 FICIs of Tedizolid in Combination with Clarithromycin and Imipenem for M. abscessus complex, and Tedizolid in Combination with Cefoxitin for M. fortuitum

Organism	Combination	Average FICI	FICI Range (Min–Max)
M. abscessus complex (n=8)	TZD/clarithromycin (day 3)	0.69	0.5–1.016
M. abscessus complex (n=4)	TZD/clarithromycin (day 14)	1.016	1.016
M. abscessus complex (n=4)	TZD/imipenem	0.82	0.75–1.03
M. fortuitum (n=5)	TZD/cefoxitin	0.36	0.3125–0.375