Randomized, crossover and single-dose bioquivalence study of two oral desogestrel formulations (film-coated tablets of 75 μg) in healthy female volunteers

Despite the increase in the substitution of branded medicinal product with generic drugs, this is a controversial issue for some pharmacological groups (such as contraceptives). The aim of the present clinical trial was to assess the bioequivalence and tolerability of two oral formulations of desogestrel. Thirty-three healthy female volunteers participated in this randomized and two-way crossover study. During two separate experimental periods, with at least four weeks of washout period, women received a single oral dose of 75 μg of desogestrel from each of the formulations (test formulation and reference formulation). Desogestrel bioavailability was determined by the measurement of 3-Ketodesogestrel plasma concentration. Pharmacokinetic parameters were comparable and the 90% CI for the ratio of C _max (96.14-114.53%) and AUC _0-t (105.73-123.83%) values for the test and reference formulations fell within the established regulatory interval (80-125%). Both formulations were also comparable in terms of tolerability. From the results of this study it can be concluded that test formulation (desogestrel 75 μg, Cyndea PHARMA S.L.) is bioequivalent to the reference formulation (Cerazet® 75 μg, Organon Española S.A.).