Volume 27, Number 1—January 2021
Research Letter
Novel 6-Month Treatment for Drug-Resistant Tuberculosis, United States
Table 1
Molecular susceptibility sequencing results and therapeutic drug monitoring data from treatment of XDR TB, Florida, USA*
Drug (dose) | Sequencing result | Date drug level drawn | Trough, µg/mL | 2h postdose level, µg/mL | 6h postdose level, µg/mL | Typical peak serum concentration, µg/mL |
---|---|---|---|---|---|---|
Bedaquiline (200 mg MWF) | No atpE (ORF) mutation detected; no Rv0678/mmpR (ORF) mutation detected | 2019 Nov 13 | 0.51 (42.25 h postdose) | 1.40 | 1.42 | 1.2–1.8 (5–6 h postdose, maintenance phase) |
N-monodesmethyl bedaquiline (metabolite) | NT | 2019 Nov 13 | 0.22 (42.25 h postdose) | 0.24 | 0.27 | NT |
Pretomanid (200 mg/d) | NT | 2019 Nov 13 | 2.07 (18.25 h postdose) | 3.43 | 2.98 | 2.3–4.3 (5–6 h postdose, at steady state) |
Linezolid (600 mg/d) | No rplC (ORF aa 84–217) mutation detected; no rrl (nt 2191–2929) mutation detected | 2019 Nov 13 | 7.62 (18.25 h postdose) | 24.15 | 17.88 | 12–26 |
Linezolid (600 mg MWF) | NT | 2020 Mar 12 | <2.00† | 19.04 | 13.6 | 12–26 |
*MWF, Monday/Wednesday/Friday; NT, not tested; ORF, open reading frame; XDR, extensively drug-resistant tuberculosis. †Trough sample was not collected; based on the apparent elimination half-life, the linezolid concentration at 48 h was calculated to be <2 µg/mL, a value associated with minimal toxicity.