Determination of the acetylator phenotype using matrix isoniazid

Area of Science:

• Pharmacogenomics
• Clinical Chemistry

Background:

• Acetylator status, a key factor in drug metabolism, influences tuberculosis treatment efficacy.
• Accurate phenotyping is crucial for optimizing isoniazid dosage and patient outcomes.

Purpose of the Study:

• To develop and validate a simple, practical method for classifying individuals as slow or rapid acetylators.
• To assess the utility of this method in a clinical setting, specifically for tuberculosis out-patients.

Main Methods:

• Urine analysis measuring the ratio of acetylisoniazid to acid-labile isoniazid.
• Administration of a slow-release isoniazid formulation followed by timed urine collection (23-24 hours).

Main Results:

• Successful classification of over 200 East African tuberculosis patients into slow and rapid acetylator phenotypes.
• Demonstration of the method's feasibility and applicability in a real-world patient cohort.

Conclusions:

• The developed method provides a straightforward approach to acetylator phenotyping.
• This technique is particularly suitable for classifying tuberculosis out-patients, potentially improving treatment management.