Background: The prevalence of drug resistance is a major challenge to TB control, and extensively drug-resistant TB (XDR-TB) forms are high mortality, highly costly to treat, and most likely to a disability, but there is a lack of research on the results in our country.

Objectives: Evaluate the treatment successes of XDR-TB cases treatment in Mongolia

Method: Data on the treatment results and histories of extensively drug-resistant TB cases diagnosed and monitored in 2016-2022 were analyzed from the NCCD's TB Surveillance Department database and analyzed.

Result: A total of 37 cases were reported in the sample, and the majority of patients were men (30 cases; 81%), almost was working age. Of these, 32 (86.5%) were previously treated and 5 (13.5%) cases were primary resistance. Treatment results: 16 (43.2%) cases were cured, 2 (5.4%) cases of treatment were completed, 3 (8.1%) cases were follow-up lost, 5 (13.5%) cases failed, and 11 (29.7%) cases died. The treatment success rate was 48.6% (18 cases); 67% (25 cases) were enrolled with Bedaquiline contained regimen, then 35% (13 cases) was the BPaL regimen. When Fisher's exact test examined the treatment outcomes of BPaL and non-BPaL regimens, the cure rate (BPAL 69%; non-BPaL 29.2%) was statistically significantly different (p=0.04).

Conclusion: The treatment success rate of XDR-TB cases was 48.6%. It is three-fold higher with the BPaL regimen than with previous regimens, and the progression rate was significantly improved.

Keywords: Extensively drug-resistant TB, BPaL, Bedaquiline