Six-month Chemotherapy Regimens in Pulmonary Tuberculosis Are as effective as a 9-month regimen

444 patients who prior to chemotherapy had pulmonary tuberculosis (verified by positive culture tests for tubercle bacilli) were eligible for study. The chemotherapy regimens were:

• Group 1 - 146 patients, for 6 months took rifampicin + isonazid with concomitant streptomycin + pyrazinamide for the initial 2 months

• Group 2 - 141 patients, for 6 months took rifampicin + isonazid with concomitant ethambutol + pyrazinamide for the initial 2 months

• Group 3 - 157 patients, for 9 months took isonazid + rifampicin with concomitant ethambutol for the initial 2 months.

373/444 subjects were followed up for 36 months (119 in Group 1, 127 in both Groups 2 and 3). Of the 71 withdrawals, 42 were lost to follow-up, 14 continued chemotherapy for a longer duration than specified, 14 died from causes other than tuberculosis and 1 patient, who had new patches of radiological shadowing, restarted chemotherapy.

Bacteriological relapse occurred in 1, 3 and 2 subjects in groups 1, 2 and 3, respectively, and all relapses occurred within 5-15 months of stopping chemotherapy. Radiological relapse was reported in 2 patients, 1 each from groups 1 and 2, at 45 and 33 months, respectively. In both these patients sputum smears were negative and they were classed as ' ... radiographic relapse without bacteriological confirmation' .

'Thus, the 6-month regimens are as effective in eliminating tubercle bacilli from the sputum and in preventing relapse as the currently recommended 9-month regimens . . . ' and ' .. . the Research Committee of the British Thoracic Society recommends the use of either of these 6-month regimens as an acceptable alternative to that already recommended, namely 9 months' chemotherapy with isoniazid and rifampicin, plus ethambutol in a dose of 25 mg/kg for the first 2 months.'

British Thoracic SOCiety. : British Journal of Diseases of the Chest 78: 330 (Oct 1984)

12 INPHARMA'"' 24 Nov 1984 0156-2703/ 84/ 1124-0012/0$01 .00/0 © ADIS Press