Abstract
A four-period, two-panel, single-rising-dose study (0.1–100 mg) was conducted in healthy males to investigate the pharmacodynamics, tolerability and pharmacokinetics of MK-0434, a steroid 5α-reductase inhibitor. MK-0434 was associated with a significant reduction in dihydrotestosterone, which was maximal at 24 h and maintained through 48 h post treatment. The maximum reduction was approximately 50 % and occurred at all doses above 5 mg (10, 25, 50 and 100 mg).
MK-0434 appeared to have no effect on serum testosterone at these single doses. Rising single doses of MK-0434 were associated with an increase in Cmax and AUC but the changes were less than proportional to dose, most likely due to nonlinear absorption. MK-0434 given in single doses up to 100 mg was without significant adverse effects in healthy male volunteers. In summary, MK-0434 is a well-tolerated, potent, orally active 5α-reductase inhibitor in man.
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Van Hecken, A., Depré, M., Schwartz, J.I. et al. Plasma concentrations and effect on testosterone metabolism after single doses of MK-0434, a steroid 5 alpha-reductase inhibitor, in healthy subjects. Eur J Clin Pharmacol 46, 123–126 (1994). https://doi.org/10.1007/BF00199874
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DOI: https://doi.org/10.1007/BF00199874