Second-Line TB Drug Usage Guidelines

Primary Indications for Second-Line TB Drugs

The European Respiratory Society recommends second-line TB drugs for patients with confirmed MDR-TB or RR-TB, as well as those with serious adverse events to first-line drugs, with a strength of evidence based on molecular or phenotypic drug susceptibility testing (DST) 1, 2
The European Respiratory Society suggests treatment with new medicines, including bedaquiline and delamanid, along with repurposed medicines like linezolid and clofazimine, for patients with XDR-TB, based on high-quality evidence from clinical trials 3, 1
Patients with resistance to fluoroquinolones or second-line injectables require specialized regimens with new and repurposed drugs, according to the European Respiratory Society, with a moderate strength of evidence 3, 4
Second-line drugs may be necessary as alternatives when patients cannot tolerate first-line medications, as recommended by the European Respiratory Society, with a low strength of evidence due to limited studies 3, 5

For individualized longer regimens, the European Respiratory Society recommends selecting drugs according to a hierarchy, including Group A (levofloxacin or moxifloxacin, bedaquiline, linezolid), Group B (clofazimine, cycloserine), and Group C (ethambutol, delamanid, pyrazinamide, ethionamide/prothionamide, p-aminosalicylic acid), with a high strength of evidence based on clinical trials 1, 6
A shorter MDR-TB regimen may be used when the patient has not been previously treated with second-line drugs, resistance to fluoroquinolones and second-line injectable agents has been excluded, and there is no intolerance to any medicine in the regimen, according to the European Respiratory Society, with a moderate strength of evidence 3, 1, 7

The European Respiratory Society recommends never adding a single effective drug to a failing regimen, as this promotes development of further drug resistance, with a high strength of evidence based on clinical trials 3, 6
Regimens should include at least five effective TB medicines during the intensive phase for longer regimens, according to the European Respiratory Society, with a moderate strength of evidence 1, 2
Treatment decisions should be made by a team of experts rather than individual physicians, as recommended by the European Respiratory Society and the American Thoracic Society, with a high strength of evidence based on expert consensus 3, 10
Regular monitoring of treatment response through monthly sputum smear and culture is essential, according to the European Respiratory Society and the American Thoracic Society, with a high strength of evidence based on clinical trials 2, 6

Antiretroviral therapy should be started as early as possible (within the first 8 weeks) following initiation of anti-TB treatment in patients with HIV co-infection, as recommended by the European Respiratory Society, with a high strength of evidence based on clinical trials 9
Elective partial lung resection may be considered in selected cases with pulmonary TB, especially those with large cavities confined to one lobe, according to the European Respiratory Society, with a low strength of evidence due to limited studies 3, 9
Second-line DST should be performed to confirm the drug resistance pattern and guide the correct choice of treatment, as recommended by the European Respiratory Society, with a high strength of evidence based on clinical trials 2