Study on Safety and Efficacy of an Oral Contraceptive in Treating Acne Papulopustulosa

1 tablet 0.030 mg ethinylestradiol / 2 mg dienogest + 1 placebo tablet daily for 21 days followed by a 7-day tablet-free interval, oral administration for 6 cycles

1 tablet 0.035 mg ethinylestradiol / 2 mg cyproterone acetate + 1 placebo tablet daily for 21 days followed by a 7-day tablet-free interval, oral administration for 6 cycles

2 placebo tablets daily for 21 days followed by a 7-day tablet-free interval, oral administration for 6 cycles