%0 Journal Article
%T Application of microbiological assay to determine pharmaceutical equivalence of generic intravenous antibiotics
%A Andres F Zuluaga
%A Maria Agudelo
%A Carlos A Rodriguez
%A Omar Vesga
%J BMC Pharmacology and Toxicology
%D 2009
%I BioMed Central
%R 10.1186/1472-6904-9-1
%X The assay is based on the concentration-dependent variation of the inhibitory effect of antibiotics on reference bacteria (B. subtilis ATCC 6633, S. aureus ATCC 6538p and S. epidermidis ATCC 12228) in a seeded agar (Difco£¿ Antibiotic Media), producing a concentration-response linear relationship with two parameters: y-intercept (concentration) and slope (potency). We compared the parameters of 22 generic products (amikacin 4, gentamicin 15, and vancomycin 3 products) against the innovator and the reference powder by Overall Test for Coincidence of the Regression Lines (Graphpad Prism 5.0).The validation method yielded excellent results for linearity (r2 ¡Ý 0.98), precision (intra-assay variation ¡Ü 11%; inter-assay variation ¡Ü 10%), accuracy, and specificity tests according to international pharmacopoeial requirements. Except for one generic of vancomycin that had 25% more API (Py-intercept = 0.001), the pharmaceutical equivalence was demonstrated in 21 generics with undistinguishable slopes and intercepts (P > 0.66). Potency estimates were 99.8 to 100.5, 99.7 to 100.2 and 98.5 to 99.9% for generic products of amikacin, gentamicin and vancomycin, respectively.The proposed method allows rapid, cost-saving, precise, and accurate determination of pharmaceutical equivalence of drugs in pharmaceutical dosage-form, and may be used as a technique for testing generic antibiotics prior to their approval for human use.Although resistance is a real and growing problem, the antimicrobials remain one of the three most prescribed drugs. Currently, the global anti-infective market is valued at US$66.5 billion with antibacterial agents accounting for over 50% of sales [1]. This remarkable cost has resulted in a massive use of generic drugs trying to assure unlimited access to cheap treatments, to the point that currently over half prescriptions include at least one generic product [2,3]. However, the phenomenal growth of generic drugs has brought concerns about their safety and effic
%U http://www.biomedcentral.com/1472-6904/9/1