Pharmaceutical Equivalence of Clarithromycin Oral Dosage Forms Marketed in Nairobi County, Kenya

Area of Science:

• Pharmaceutical Sciences
• Drug Quality Assessment
• Pharmacokinetics

Background:

• Clarithromycin is a vital macrolide antibiotic used for various infections, including pneumonia and H. pylori.
• Ensuring pharmaceutical equivalence of generic drugs is crucial for patient safety and treatment efficacy.
• In vitro dissolution testing is a key method for predicting in vivo drug performance.

Purpose of the Study:

• To assess the pharmaceutical equivalence of generic clarithromycin products available in Nairobi, Kenya.
• To compare in vitro dissolution profiles of generic and innovator clarithromycin formulations.
• To evaluate the suitability of similarity factor (f₂) in demonstrating drug product equivalence.

Main Methods:

• 14 generic and 4 innovator clarithromycin products (tablets, capsules, suspensions) were analyzed.
• Products underwent assay testing and comparative dissolution studies at pH 1.2, 4.5, and 6.8.
• Dissolution profiles were evaluated using similarity factor (f₂) calculations.

Main Results:

• All products met pharmacopoeial assay specifications.
• Significant variations in dissolution profiles were observed across generic products.
• Non-compliance rates for tablets/capsules ranged from 33% to 50% across different pH levels.
• None of the tested suspensions met compliance criteria for dissolution.
• Only 25% of all products achieved the required similarity factor (f₂) with innovator products.

Conclusions:

• A substantial proportion of generic clarithromycin products marketed in Nairobi are not pharmaceutically equivalent to innovator brands.
• Standard assay and single-point dissolution tests are inadequate for demonstrating bioequivalence.
• Further investigation into dissolution testing methodologies is recommended to ensure generic drug quality.