Although this article is from 2009, I thought it would be an interesting read considering it was one of the most viewed articles listed on the American Journal of Health Systems Pharmacists’ website. The article explores vancomycin monitoring in hospitalized patients to treat gram-positive infections, typically MRSA. It was found that earlier formulations of vancomycin might have been the reason for some serious adverse effects including nephrotoxicity and ototoxicity (toxicity to the ear). These formulations possibly contained impurities. The study found that the AUC, or area under the curve, is the most useful pharmacokinetic parameter to monitor vancomycin administration. Various other methods of monitoring are recommended when obtaining vancomycin serum concentration is not possible, but more clinical data would be necessary.
The article mentioned a lack of clinical data hindering the results of this study. It was stated that due to vancomycin being a generic formulation that very few newer clinical trials had actually been conducted. It was also noted that pediatric monitoring was beyond the scope of the article. Now that we are learning a lot about the drug development process it was interesting to read about a case where this process actually hindered further research for companies.
While a lot of the pharmacokinetic terms were familiar thanks to the Principles of Drug Action course material, it was definitely a newer concept to learn that vancomycin metabolism differed significantly for diabetic patients. Drug dosing, especially with a drug like vancomycin with such a narrow therapeutic index, should be done strategically. A patient’s medical history needs to be carefully reviewed when deciding how to dose a patient, which should be a very individualized process.
Rybak M, Lomaestro B, Rotschafer JC et al. Therapeutic monitoring of vancomycin in adult patients: A consensus review of the American Society of Health-System Pharmacists, the Infectious Diseases Society of America, and the Society of Infectious Diseases. Am J Health-Syst Pharm. 2009; 66:887-98.