Therapies containing rifamycin for three months or more were reasonably well-tolerated and efficacious for preventing active tuberculosis (TB) in patients with latent TB infection (LTBI), according to a study being published in Annals of Internal Medicine.
In countries with low incidence of TB, many new cases emerge as a result of reactivated LTBI. Current treatments are effective and safe for preventing reactivation, but they are lengthy, which may affect completion rates. The authors suggest that global elimination of TB depends on shorter, effective, and well-tolerated LTBI regimens. New regimens that may be more effective are being introduced, but few studies directly compare these newer options. Researchers conducted a network meta-analysis of 53 trials to address the benefits and harms of 15 regimens aimed at preventing active TB in patients with LTBI. They utilized a network meta-analysis approach because it enables the indirect comparison of regimens and thus produces inferences of relative efficacy that would not otherwise be possible. The evidence suggests that currently recommended regimens are efficacious, but regimens containing rifamycin, given for 3 months or more, may be just as, if not more, effective than prolonged isoniazid (INH) monotherapy for treating LTBI.
An accompanying editorial suggests that this network meta-analysis is important because it provides clear evidence that it is time to move away from INH as a primary therapy for LTBI and towards rifamycin-containing regimens that provide better protection against TB, greater safety, and shorter duration of treatment.