Incorporating dried blood spot LC-MS/MS analysis for clinical development of a novel oncolytic agent.

Aim: Design and execution of a dried blood spot (DBS-LC-MS/MS) assay for pharmacokinetic analyses in oncology patients.

Results & Discussion: The methodology was validated to collect and store DBS samples from multiple clinical sites, and analyze blood with diverse hematocrit ranges (25-55) to match the potential patient population. Bridging data comparing DBS and plasma showed high degree of concordance with DBS:plasma ratios of 0.

Synthesis of C-14 radiolabeled glucagon receptor antagonist and its use in a human mass balance study.

The synthesis of the radiolabeled glucagon receptor antagonist 1-[ C] was accomplished based on decarboxylative iodination of acid 2 followed by "reattachment" of C carboxylic function. The method allowed a significant reduction in the number of steps in preparation of the radiolabeled compound. Iodide 4, obtained by the halodecarboxylation, was converted to cyanide 5-[ C], which was hydrolyzed to provide the radiolabeled acid 2-[ C].

Amount of Testosterone on Laundered Clothing After Use of Testosterone Topical 2% Solution by Healthy Male Volunteers.

Introduction: Testosterone 2% solution (Axiron) applied to armpit(s) is used for replacement therapy in men with a deficiency of endogenous testosterone.

Aim: To determine the amount of testosterone on subjects' T-shirts 12 hours after applying testosterone solution, the residual testosterone on subjects' T-shirts after laundering, and the testosterone transferred to unworn textile items during laundering with worn T-shirts.

Methods: Healthy males ≥18 years old applied 2 × 1.

Effect of deodorant and antiperspirant use and presence or absence of axillary hair on absorption of testosterone 2% solution applied to men's axillae.

Introduction: Testosterone 2% solution is applied to axillae and is indicated for testosterone replacement therapy in males deficient in endogenous testosterone.

Aim: This open-label crossover study evaluated the effect of deodorant/antiperspirant use and presence or absence of axillary hair on absorption of testosterone solution.

Methods: Healthy males (N = 30; ≥50 years of age with baseline testosterone <400 ng/dL) were randomized to one of four treatment sequences involving six treatments.

Development and validation of a liquid chromatography-tandem mass spectrometric method for the determination of the major metabolites of duloxetine in human plasma.

A sensitive bioanalytical method for the measurement of two major circulating metabolites of duloxetine [4-hydroxy duloxetine glucuronide (LY550408) and 5-hydroxy-6-methoxy duloxetine sulfate (LY581920)] in plasma is reported. This method produced acceptable precision and accuracy over the validation range of 1-1000 ng/mL. Several issues had to be addressed in order to develop an LC/MS/MS assay for these metabolites.