Table 1.

Grouping of antitubercular drugs for design of regimens for treatment of drug-resistant tuberculosis

WHO Guidelines 201456		WHO Guidelines 201651		WHO Guidelines 20191
Group	Anti-TB Drugs	Group	Anti-TB drugs	Group	Anti-TB Drugs
Group 1 First-line oral agents	Z E Rfb	Group A Fluoroquinolones	Lfx Mfx Gfx	Group A Include all three drugs in regimen, unless contraindicated	Lfx or Mfx Bdq Lzd
Group 2 Injectable agents	S Km Am Cm	Group B Second-line injectable agents	Am Cm Km	Group B Addition of one or both drugs	Cfz Cs or Trd
Group 3 Fluoroquinolones	Lfx Mfx Ofx	Group C Other core second-line agents	Eto Pto Cs Trd Lzd Cfz	Group C Addition of these drugs to complete regimen when drugs from abovementioned groups cannot be used	E Dlm Z Ipm-Cln or Mpm Am or S Eto or Pto PAS
Group 4 Oral bacteriostatic second-line agents	Eto Pto Cs Trd PAS	Group D Add-on agents	D1 Z E High-dose H
Group 5 Drugs with unclear efficacy or unclear role in MDR-TB treatment, not recommended by WHO for routine use in MDR-TB patients	Bdq Dlm Lzd Cfz Amx-Clv Ipm-Cln Mpm High-dose H T Clr		D2 Bdq Dlm
D3 PAS Ipm-Cln Mpm Amx-Clv T

Abbreviations: H, isoniazid; R, rifampicin; E, ethambutol; Z, pyrazinamide; Rfb, rifabutin; S, streptomycin; Km, kanamycin; Am, amikacin; Cm, capreomycin; Ofx, ofloxacin; Lfx, levofloxacin; Mfx, moxifloxacin; Gfx, gatifloxacin; Eto, ethionamide; Pto, protionamide; PAS, P-aminosalicylic acid; Cs, cycloserine; Cfz, clofazimine; Lzd, linezolid; Clr, clarithromycin; Bdq, bedaquiline; Dlm, delamanid; Ipm-Cln, imipenem–cilastatin; Mpm, meropenem; Amx-Clv, amoxycillin–clavulanate; T, thioacetazone.