Interruptions of individual drug(s) or of the whole treatment may lead to the emergence of new resistances. Moreover, in case of treatment interruption, drugs with a long half-life such as bedaquiline or clofazimine remain in the blood for several months. In practice, it is as if the patient is receiving bedaquiline and/or clofazimine alone, which increases the risk of developing resistance to these drugs.
Problems of treatment interruption by the patient (e.g. discontinuation of certain drugs, recurrent treatment interruptions) should be detected and addressed (management of adverse effects if necessary and reinforcement of patient support measures).
Patients who have interrupted the whole treatment for 2 months or more meet the definition of patients "lost to follow-up" (Chapter 17). If the patient returns, repeat bacteriological tests (RMT, culture and full pDST and/or genome sequencing) to detect potential new resistance. Based on RMT results, start a new regimen while waiting for full DST results, then adjust treatment accordingly.
For patients who have interrupted the whole treatment for 4 weeks or more but less than 2 months, perform new bacteriological tests as above. Based on the patient's clinical status and RMT results, start a new regimen or resume treatment at the point it was interrupted while waiting for full DST results, then adjust treatment accordingly. If the interrupted treatment is resumed, doses missed during interruption must be made up to complete the treatment.