Background:  The duration of anti-tuberculosis (TB) treatment among HIV⁺ patients with TB is still a contentious issue. A 6-month intermittent (3/week) regimen is the standard treatment for TB in the national program in India and many countries. We wanted to compare the efficacy of a 6-month vs a 9-month intermittent anti-TB regimen among HIV⁺ patients with TB.

Methods:  This ongoing, prospective, randomized, controlled clinical trial was conducted with 2 arms:  arm A was the 6-month regimen 2EHRZ₃/4RH₃; arm B was the 9-month regimen 2EHRZ₃/7RH₃ (E: ethambutol 1200 mg, H: isoniazid 600 mg, R: rifampicin 450/600 mg, and Z: pyrazinamide 1500 mg with pyridoxine 10 mg, 3 days/week). Treatment was fully supervised for the first 2 months, then once a week. The intensive phase was extended by 4 weeks if sputum smears were positive at the second month. Patients were followed every month with clinical exam, sputum AFB smear and culture for M. tuberculosis. Chest radiograph and CD4 counts were done at baseline and at the end of therapy. None of the patients were on ART. End points were sputum culture negativity at end of treatment and relapses. Intent to treat analysis was performed. c² test was used to compare proportion of responses between the 2 groups.

Results:  We randomized 158 HIV⁺ patients with culture-confirmed pulmonary TB to arm A (n = 81) or arm B (n = 77). At baseline, sputum smear was positive for AFB in 77% of patients and mean CD4 count was 201 ± 230 cells/mm³. At 2 months, sputum smear was negative in 70% of patients while culture was negative in 84% (151 patients available for evaluation). Of the total, 11 patients died during treatment, 5 defaulted, 19 required a change of treatment while 1 is on treatment; overall favorable response was 78%. Of 122 patients evaluated at the end of treatment, sputum smear was negative in 93% in arm A and 98% in arm B while culture was negative in 99% and 95% of patients, respectively (ns). Mean CD4 count at completion of ATT in both groups was 197 ± 153 cells/mm³. Of 122 patients who completed regular therapy and who were declared cured, there were 16 relapses (7 in arm A and 9 in arm B, ns).

Conclusions:  A 6-month regimen of thrice-weekly anti-TB therapy resulted in a high cure rate, similar to the 9-month regimen. Relapse appeared to be similar in the 2 arms; follow-up is ongoing. These results have implications for TB treatment programs in resource-constrained countries.

Keywords: anti-tuberculosis treatment; pulmonary tuberculosis; clinical trial