Evaluation of Effectiveness and Safety of a New Short-Course Chemotherapy Regimen for Drug-Susceptible Tuberculosis

The objective: to compare effectiveness and safety of treatment of drug-susceptible tuberculosis when using four-month and six-month chemotherapy regimens.

Subjects and Methods. A multicenter cohort study was conducted from October 2023 to August 2025 to study treatment of drug-susceptible tuberculosis using a short-course (four-month) regimen (SC Group) of chemotherapy (CT) compiled of the following agents: rifapentine (900 mg daily), isoniazid, pyrazinamide, and levofloxacin in the intensive phase for two months and rifapentine (900 mg daily), isoniazid, and pyrazinamide in the continuation phase. Comparison Group (CG) included patients who received a six-month chemotherapy regimen for drug-susceptible tuberculosis during the same period. Effectiveness was assessed by sputum conversion and clinical and radiological changes.

Results. Effective treatment was achieved in 92.0% (46/50) of patients in Short-Course Regimen Group versus 76.6% (46/60) in Comparison Group (p = 0.038). Sputum conversion by smear according to microscopy data by the end of therapy was registered in 96.0% (48/50) and 76.7% (46/60), respectively (p = 0.005); and sputum conversion by culture was reported in 94.0% (47/50) and 73.3% (44/60) (p = 0.004). The overall frequency of adverse reactions was significantly lower in the Short-Course Regimen Group (57.7% vs. 74.6%; p = 0.045). 

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