Abstract

OBJECTIVE:

Andriol Testocaps is a new oral formulation of testosterone undecanoate (TU) for treatment of hypogonadism. As TU is taken up by the intestinal lymphatic system, both the presence and the composition of food influence the absorption. The aim of this study was to investigate the effect of food composition on the pharmacokinetics of oral TU.

DESIGN:

An open-label, single-centre, four-way crossover study. With a washout period of 6-7 days, 80 mg TU was administered in the morning 5 min after consuming each of four different meals in a randomized order (A: 230 kcal, 0.6 g lipid; B: 220 kcal, 5 g lipid; C: 474 kcal, 19 g lipid; D: 837 kcal, 44 g lipid).

PATIENTS:

Twenty-four postmenopausal volunteers.

MEASUREMENTS:

Serial blood samples were collected until 24 h after dosing to determine testosterone and dihydrotestosterone (DHT) by gas chromatography-mass spectroscopy (GC-MS).

RESULTS:

The bioavailability of testosterone after a low-calorie meal containing 0.6 g lipid or 5 g lipid was relatively low, the area under the concentration-time curve (AUC(0-tlast)) for testosterone being 30.7 and 43.5 nmol h/l, respectively. The bioavailability of testosterone after a meal containing 19 g lipid was considerably higher (AUC(0-tlast) = 146 nmol h/l), whereas increasing the lipid content to 44 g lipid did not further increase the bioavailability of testosterone (AUC(0-tlast) = 154 nmol h/l).

CONCLUSION:

Approximately 19 g of lipid per meal efficiently increases absorption of testosterone from oral TU. Therefore, coadministration with a normal rather than a fatty meal is sufficient to increase serum testosterone levels when using oral TU.