Abstract:
Objective: To evaluate the pharmacokinetics of standard doses of rifampicin (RMP) in fixed dose combination in pulmonary
tuberculosis patients by a modified high performance liquid chromatography (HPLC) method
Materials and Methods: This descriptive study was conducted after approval from Ethical Committee, Army Medical College
Rawalpindi and was funded in part by National University of Sciences and Technology (NUST), Islamabad. Twenty adult
patients with newly diagnosed pulmonary TB consented to participate in the study. RMP plasma concentrations were assayed
by a simple and sensitive HPLC method in the initial phase of pulmonary tuberculosis treatment. The method was modified
to use naproxen as an internal standard and validated according to International Conference on Hormonization (ICH) guidelines.
Results: The calibration curve of rifampicin was linear within the range of 0.781–50 μg/ml. Both intra-day and inter-day
variability and accuracy demonstrated good reproducibility at all quality control levels. The developed method was found to
be simple, precise and accurate for estimation of rifampicin in plasma. The pharmacokinetic parameters of RMP showed marked
inter-individual differences and sub-therapeutic levels.
Conclusion: Evaluation of pharmacokinetics of standard doses of rifampicin in fixed dose combination in pulmonary tuberculosis
patients by a modified high performance liquid chromatography (HPLC) method is precise, accurate and cost-effective. It may
be used for monitoring plasma RMP levels in TB patients who are slow to respond or are non-responders and have less availability
of resources.
