Evaluation of Effectiveness of 9- and 6-Month Treatment Regimens in Patients with Multiple Drug Resistant or Rifampicin-Resistant Tuberculosis in the Republic of Belarus

The objective: to evaluate the effectiveness of 39- and 24-week treatment regimens in patients with multiple drug resistant or rifampicin-resistant tuberculosis (MDR/RR-TB).Subjects and Methods. We evaluated the effectiveness of 39- and 24-week treatment regimens containing bedaquiline, levofloxacin, linezolid, clofazimine, and cycloserine or delamanid (modified short-course regimens - mSCR) and bedaquiline, pretomanid, linezolid, and moxifloxacin (BPaLM), in cohorts of patients with MDR/RR-TB. Results. Of the 550 and 139 patients were included in the mSCR and SMARRTT Studies (BPaLM regimen) from December 2019 to October 2021 and from March 2022 to August 2022, 90.7% (487/537) and 94.2% (131/139) achieved a successful treatment outcome, respectively, 13 patients were excluded from the mSCR Study and continued treatment according to an individual regimen. Median (ME) and quartiles [Q1-Q3] of sputum culture conversion time in patients treated with mSCR and BPaLM made 30.0 (25.0-56.0) and 27.0 (25.0-29.8) days (p<0.01) respectively. The prognostic factor for an unfavorable outcome for the BPaLM and mSCR regimens was a positive sputum microscopy result before treatment (OR – 7.92, 95% CI 1.5 – 41.0, p = 0.014; OR – 1.97, 95% CI 1.1–3.5, p=0.02, respectively), and for the mSCR regime, the time of sputum culture conversion >90 days was an additional prognostic factor (OR – 3.35, 95% CI 1.2–9.5, p=0.03) .Conclusions. The effectiveness of the mSCR and BPaLM regimens in patients with MDR/RR-TB is high (90.7% and 94.2%, respectively). Patients with positive sputum microscopy and late sputum culture conversion have a lower chance of cure.