9.8 Treatment adaptation and change of treatment

9.8.1 Treatment adaptation

The whole treatment or individual drug(s) may be temporarily interrupted by the clinician in case of severe adverse effects (Appendix 17).

This is considered as treatment adaptation, as long as it does not meet the definition of "treatment failure" (Chapter 17).

9.8.2 Change of treatment

The clinician should replace the DS-TB treatment with:

• A treatment for isoniazid-resistant TB (Hr-TB) when RMT or pDST shows:
  • the development of isoniazid resistance (Chapter 11) after treatment initiation, or
  • undetected isoniazid resistance at baseline, for any reason.

• A treatment for multidrug-resistant or rifampicin-resistant TB (MDR/RR-TB, Chapter 10) in the following circumstances [1] Citation 1. World Health Organization. Meeting report of the WHO expert consultation on drug-resistant tuberculosis treatment outcome definitions, 17-19 November 2020. Geneva: World Health Organization; 2021.
  https://www.who.int/publications/i/item/9789240022195 :
  • Development of rifampicin resistance after treatment initiation.
  • Rifampicin resistance not detected at baseline, for any reason.
  • No bacteriological conversion or bacteriological reversion (Chapter 17).
  • Insufficient clinical response to treatment in patients:
    • with non-bacteriologically confirmed TB (e.g. miliary TB, some forms of EPTB, TB in children).
    • with bacteriologically confirmed TB, when the bacteriological response cannot be assessed, or the result is inconclusive.

The above treatment changes meet the outcome definition of "treatment failure" (Chapter 17), except when the reason for change is a resistance undetected at baseline [1] Citation 1. World Health Organization. Meeting report of the WHO expert consultation on drug-resistant tuberculosis treatment outcome definitions, 17-19 November 2020. Geneva: World Health Organization; 2021.
https://www.who.int/publications/i/item/9789240022195 .