Monitoring the ingestion of anti-tuberculosis drugs by simple non-invasive methods
International Journal of Pharmaceutics
Medical Biochemistry, DST/NRF Centre of Excellence for Biomedical TB Research, Stellenbosch University, P.O. Box 19063, Tygerberg 7505, South Africa; MRC Biostatistics Unit, Tygerberg, South Africa; Division of Pharmacokinetics and Drug Therapy, Department of Biopharmaceutical Sciences, Uppsala University, Sweden; Division of Clinical Pharmacology, University of Cape Town, South Africa; Department of Paediatrics and Child Health, Tygerberg, South Africa
This investigation retrospectively assessed inexpensive non-invasive qualitative methods to monitor the ingestion of anti-tuberculosis drugs isoniazid, rifampicin and rifapentine. Results showed that commercial test strips detected the isoniazid metabolites isonicotinic acid and isonicotinylglycine as efficiently as the isonicotinic acid method in 150 urine samples. The presence of rifamycins in urine samples (n = 1085) was detected by microbiological assay techniques and the sensitivity compared to the n-butanol extraction colour test in 91 of these specimens. The proportions detected by the two methods were significantly different and the sensitivity of the n-butanol procedure was only 63.8% (95% CL 51.2-76.4%) as compared to that of the superior microbiological method. Final validation (n = 691) showed that qualitative assays measure isoniazid and rifamycin ingestion with an efficiency similar to high-performance liquid chromatography. The qualitative procedures may therefore be valuable in clinical trials and in tuberculosis clinics to confirm drug ingestion. © 2005 Elsevier B.V. All rights reserved.
butanol; drug metabolite; isoniazid; isonicotinic acid; isonicotinylglycine; rifampicin; rifamycin; rifapentine; tuberculostatic agent; unclassified drug; article; drug monitoring; extraction; high performance liquid chromatography; human; ingestion; intermethod comparison; major clinical study; microbiology; non invasive procedure; priority journal; qualitative analysis; retrospective study; sensitivity analysis; test strip; urinalysis; validation process; Antitubercular Agents; Drug Monitoring; Humans; Isoniazid; Isonicotinic Acids; Microbial Sensitivity Tests; Patient Compliance; Reproducibility of Results; Retrospective Studies; Rifampin; Self Administration; Staphylococcus aureus