UHPLC-MS/MS bioanalysis of urinary DHEA, cortisone and their hydroxylated metabolites as potential biomarkers for CYP3A-mediated drug-drug interactions.

AIM: A UHPLC-MS/MS assay was developed to quantify urinary dehydroepiandrosterone (DHEA), 7ß-hydroxy-DHEA, cortisone and 6ß-hydroxycortisone as potential biomarkers to predict CYP3A activity. RESULTS: A sensitive assay at LLOQ of 0.500 ng/ml with good accuracy and precision was developed for the four analytes in human urine. This UHPLC-MS/MS assay was optimized by eliminating nonspecific loss of the analytes in urine, ensuring complete hydrolysis of the conjugates to unconjugated forms and use of the product ions of [M+H-H2O]+ for multiple reaction monitoring detection of DHEA and 7ß-hydroxy-DHEA. CONCLUSION: This assay was successfully applied to a pilot clinical study. It is also suitable for future drug-drug interaction studies to continue evaluating the potential of these steroids as biomarkers for CYP3A inhibition and induction.

The standardization of nonsterile compounding: a study in quality control and assessment for hormone compounding.

Sterile and nonsterile compounding of medication has attracted much attention over the last few years due to the onset of various infections and negative compounding practices. This paper reports on the standardization of compounded hormones utilizing the Wiley Protocol, which provides nonsynthetic bioidentical estradiol, progesterone, dehydroepiandrosterone, and testosterone in a transdermal topical cream base for women and men in a standardized dosing regimen. Here, we present data from 2008 through 2012, which details the process of standardization and quality testing of the hormones through submission of random compounded samples for quality control and assessment. Pharmacies delivering the Wiley Protocol were required to follow the same compounding formulation, as well as submit random samples for quarterly testing. Sample concentrations were tested using high-performance liquid chromatography. We found that pharmacies that submitted samples had a 91% passing rating with a percent of target of 98.6% +/- 8.4%. It was also determined that pharmacies that prepared more compounded cream had a higher passing rating than those that prepared limited quantities. We found that standardization across multiple pharmacies could be achieved through quarterly testing of submitted samples by a third-party laboratory when following necessary procedures as defined by the Wiley Protocol. It was also determined that experience and training were a critical factor in the mixing of compounded prescriptions, with high consistency and accuracy providing patient safety.

Determination of dehydroepiandrosterone sulfate in human plasma by gas chromatography/mass spectrometry using a deuterated internal standard: a method suitable for routine clinical use.

A capillary gas chromatographic-mass spectrometric method for the determination of dehydroepiandrosterone sulfate (DHEA-S) in human plasma is described. [7,7-2H2]DHEA-S is used as internal standard. After desulfation by methanolysis, heptafluorobutyryl derivatives are prepared, and selected ion monitoring of characteristic fragment ions--m/z 270 for DHEA and m/z 272 for [7,7-2H2]DHEA--carried out. Requiring small amounts of plasma, the rapid, convenient work-up and the application of bench-top GC/MS instrumentation proved our method to be suited for routine clinical use in adults and children. The method needs no complex corrections for isotope contributions and provides good accuracy and precision. Comparative values of samples assayed by our GC/MS procedure and by a direct RIA indicated that the RIA overestimates the true concentration.