Split‐drug regimens for the treatment of patients with sputum smear‐positive pulmonary tuberculosis – a unique approach

SummaryObjective  To evaluate the efficacy of split‐drug regimens for treatment of patients with sputum smear‐positive pulmonary tuberculosis in south India.Design  Randomized controlled clinical trial where eligible patients were randomly allocated to: (i) 2RE3HZ3(alt)/4RH2 (split I): rifampicin plus ethambutol given on one day and isoniazid plus pyrazinamide the next day for first 2 months followed by rifampicin plus isoniazid twice weekly for 4 months, or (ii) 3RE3HZ3(alt)/3RH2 (split II): similar to regimen 1, except duration was 3 months in each phase, or (iii) 2REHZ3/4RH2 (control): rifampicin, isoniazid, ethambutol and pyrazinamide, given thrice weekly for 2 months followed by isoniazid and rifampicin twice weekly for 4 months. All patients were followed up clinically and bacteriologically every month up to 2 years and every 6 months for up to 5 years.Results  A favourable response (cultures negative for Mycobacterium tuberculosis during the last 2 months of treatment) was observed in 91% of 407 patients in split I, 94% of 415 in split II and 89% of 418 in the control regimen. Ninety‐one per cent of 370 patients in split I, 93% of 389 in split II and 90% of 370 in control regimens had quiescent disease at the end of 60 months. Gastrointestinal symptoms were more frequent under the control regimen (P = 0.01).Conclusion  Split‐drug regimens were as effective as the control regimen in terms of favourable response at the end of treatment and quiescent disease at 5 years, and caused fewer gastrointestinal side‐effects.