2.2. Clinical setting and baseline patients’ characteristics

The study was conducted at four Mongolian and five Ukrainian TB hospitals and dispensaries between 2014 and 2018. The main eligibility criteria were an informed consent and positive sputum smear at study entry. All patients had one or more symptoms of pulmonary TB such as low-grade fever, cough, chest pain, dyspnea, hemoptysis, and weight loss. Patients in each country were randomly allocated by computer-generated sequence into two groups at 2:1 ratio, to receive in double-blinded fashion either V7 pills or identically appearing placebo pills without M. vaccae. The randomization resulted in equal distribution of baseline characteristics; ethnicity, age, gender, height, body weight, blood cell counts, serum biochemistry parameters, severity and various manifestations of the disease. Thus, the statistical bias due to population heterogeneity was unlikely. The distribution of patients with: DS-TB; MDR-TB; XDR-TB and TB-HIV was 45:45:1:9 and 22:20:1:9 in V7 and placebo arms respectively, which did not differ statistically (Chi-square, P = 0.13). Some of the patients, especially those with drug-resistant TB, required individualized treatment rather than standard 1^st line TB drugs; the proportion of such patients was dependent from their baseline diagnosis in V7 and placebo arms; the inter-group difference was not statistically significant (Fisher's two-tailed, P = 0.85). Remaining patients were prescribed conventional 2HREZ/4HR regimen, occasionally supplemented with streptomycin. In Mongolia all patients - except one re-treated case in each arm - were conditionally categorized as DS-TB since information on their drug resistance status and HIV infection was not available at the time of treatment initiation.