Investigation of Bioequivalence of Ethinylestradiol (EE) and Drospirenone (DRSP) in Two Different Tablet Formulations: Yasmin and Yasmin + Levomefolate Calcium (Metafolin) & L-5-MTHF in Two Different Tablet Formulations: Levomefolate Calcium (Metafolin) and Yasmin + Levomefolate Calcium (Metafolin)

Open-label, Randomized, Three-fold Crossover Study to Investigate the Bioequivalence of Two Different Tablet Formulations Containing 0.03 mg Ethinylestradiol (EE) and 3 mg Drospirenone (DRSP) Without [SH T470FA] and With [SH T04532A] 0.451 mg Metafolin®, and to Investigate the Bioequivalence of Two Different Tablet Formulations Containing 0.451 mg Metafolin® Without [SH T04532C] and With 0.03 mg EE/ 3 mg DRSP [SH T04532A] in 42 Healthy Young Women

The purpose of this study is to examine and compare the uptake of Yasmin (oral contraceptive containing drospirenone and ethinylestradiol) with or without levomefolate calcium (Metafolin, a registered vitamin supplement) in the body and to examine and compare the uptake of levomefolate calcium with or without Yasmin in the body, in healthy volunteers not using hormonal contraception.

Inclusion Criteria:

• Healthy female volunteer
• Age: 18 - 38 years inclusive
• Body mass index (BMI)1: ≥ 19 and < 28 kg/m²
• Regular cyclic menstrual periods at screening OR when using combined oral contraceptives during the recruitment period reporting of natural cyclic menstrual periods prior to their use
• Willingness to use non-hormonal methods of contraception during the complete trial OR previous tubal ligation

Exclusion Criteria:

• incompletely cured pre-existing diseases for which it can be assumed that the absorption, distribution, metabolism, excretion and effect of the study drugs will not be normal
• known or suspected sex-steroid influenced malignancies
• endometrial hyperplasia; genital bleeding of unknown origin; uterus myomatosus
• known or suspected tumors of the liver and pituitary
• presence or history of severe hepatic disease as long as liver function values have not returned to normal
• severe renal insufficiency or acute renal failure
• thrombophlebitis, venous / arterial thromboembolic diseases; presence or history of prodromi of a thrombosis
• other conditions that increase susceptibility to thromboembolic diseases
• known neuropsychiatric diseases, especially known or suspected epilepsy, and/ or deficient status of folate or vitamin B12
• use of any other medication within 2 cycles before first study drug administration which could affect the study aim
• use of potassium sparing drugs; use of folic acid containing supplements or medicines or use of any medication within 2 cycles before first study drug administration known to interfere with folate metabolism
• inadequate folate and/or Vitamin B12 status , clinically relevant deviations in red cell folate concentrations