Union Study shows long-term effectiveness for shortened DR-TB treatment regimen up to 24 months after treatment completion

Results from a Union-led observational study published in The Lancet’s EClinicalMedicine, show that a nine-month shortened treatment regimen for rifampicin-resistant tuberculosis (RR-TB) delivered to patients under programmatic conditions maintains a good level of effectiveness up to 24 months after completion. Until now there has been limited data on the long-term effectiveness of this treatment regimen after completion.

The study reports on the outcome during treatment and after completion of the injectable-containing shortened regimen using kanamycine and normal-dose moxifloxacin for 1006 people from nine francophone African countries. Sputum cultures were collected every six months up to 24 months following their treatment completion. The risk of any unfavourable outcome, of failure and relapse, and of death during and after treatment was analysed according to individual characteristics and initial drug susceptibility. 79.3 percent of people who underwent this treatment during the 2013-2015 inclusion period had a relapse-free successful outcome with 9.6 percent of people having a combined failure and relapse after 24 months. These programmatic results are very similar to those produced in the STREAM stage 1 randomised clinical trial.

“We believe that these results are of high public health relevance by showing the good long-term outcomes of this regimen in low-and middle-income settings”, said Valérie Schwoebel, lead author of the study and consultant for The Union. “We hope to see similar high-quality data on the long-term post-treatment success for other regimens, including all-oral shorter treatment regimens for drug-resistant TB.”

According to the latest data of the World Health Organization (WHO), treatment outcomes for people with multidrug-resistant (MDR) and RR-TB show a global treatment success rate of 56 percent. The majority of these patients are expected to benefit through use of shorter treatment regimens. The regimen used in this study was included in the 2016 WHO guidelines as a recommended regimen. WHO’s 2018 revision to the guidelines maintained this recommendation with additional precautions and exclusion criteria.

The results support the WHO recommendation that all people with RR-TB be offered drug susceptibility testing for fluoroquinolones and reinforces the WHO 2018 recommended use of this regimen for patients with RR-TB likely to be susceptible to the newest generation of fluoroquinolones, but does not support exclusion criteria based on resistance to drugs other than fluoroquinolones.

The Union provides practical and experience-based support to countries implementing treatments for drug resistant TB. Results published recently from another Union-led study, which evaluated the management of RR-TB in Niger from 2008 to 2016 following the national roll out of the injectable-containing shorter treatment regimen, showed 83 percent relapse-free success.

The Union supports the move to all-oral treatments for RR-TB. Collection of high-quality data on all-oral short regimens, including evaluation of relapse rates, should continue in operational research conditions to provide additional evidence to ensure that these regimens continue to improve the outcomes for people with drug-resistant TB. 



 

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