title: Using a single tablet daily to treat latent tuberculosis infection in Brazil: bioequivalence of two different isoniazid formulations (300 mg and 100 mg) demonstrated by a sensitive and rapid high-performance liquid chromatography-tandem mass spectrometry method in a randomised, crossover study.
abstract: The recommended treatment for latent tuberculosis (TB) infection in adults is a daily dose of isoniazid (INH) 300 mg for six months. In Brazil, INH was formulated as 100 mg tablets. The treatment duration and the high pill burden compromised patient adherence to the treatment. The Brazilian National Programme for Tuberculosis requested a new 300 mg INH formulation. The aim of our study was to compare the bioavailability of the new INH 300 mg formulation and three 100 mg tablets of the reference formulation. We conducted a randomised, single dose, open label, two-phase crossover bioequivalence study in 28 healthy human volunteers. The 90% confidence interval for the INH maximum concentration of drug observed in plasma and area under the plasma concentration vs. time curve from time zero to the last measurable concentration "time t" was 89.61-115.92 and 94.82-119.44, respectively. The main limitation of our study was that neither adherence nor the safety profile of multiple doses was evaluated. To determine the level of INH in human plasma, we developed and validated a sensitive, simple and rapid high-performance liquid chromatography-tandem mass spectrometry method. Our results showed that the new formulation was bioequivalent to the 100 mg reference product. This finding supports the use of a single 300 mg tablet daily strategy to treat latent TB. This new formulation may increase patients' adherence to the treatment and quality of life.
authors.affiliation: Farmanguinhos, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.
authors.forename: André
authors.initials: A
authors.lastname: Daher
authors.affiliation: Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.
authors.forename: Luciana
authors.initials: L
authors.lastname: Pitta
authors.affiliation: Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.
authors.forename: Tereza
authors.initials: T
authors.lastname: Santos
authors.affiliation: Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.
authors.forename: Draurio
authors.initials: D
authors.lastname: Barreira
authors.affiliation: Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil.
authors.forename: Douglas
authors.initials: D
authors.lastname: Pinto
mesh_terms: D000293:Adolescent; D000328:Adult; D000995:Antitubercular Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D007538:Isoniazid / Q000008:administration & dosage / Q000493:pharmacokinetics*; D055985:Latent Tuberculosis / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D013607:Tablets; D053719:Tandem Mass Spectrometry; D013810:Therapeutic Equivalency; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents; D013607:Tablets; D007538:Isoniazid