Ethinyl Estradiol/Gestodene

Pharmacokinetic (PK) interactions between the cytochrome P450 3A4 (CYP3A4) pathway and transdermally administered ethinyl estradiol (EE) and gestodene (GSD) were investigated. This paper reports the findings of three open-label, intra-individual, one-way crossover, Phase I trials. In two studies, women used a novel contraceptive patch for 3 weeks during two 4-week study periods; in the second period, the CYP3A4 inhibitors erythromycin (Study 1) or ketoconazole (Study 2) were administered concurrently. In a third study, women received single doses of the CYP3A4 model substrate midazolam, alone and after 3 weeks of concurrent patch application. In each period, the EE/GSD patch (delivering low EE and GSD doses resulting in the same systemic exposure as a combined oral contraceptive containing 0.02 mg EE and 0.06 mg GSD) was applied once weekly for 3 weeks, with one patch-free week. Erythromycin, ketoconazole, and midazolam were administered orally. Main outcome measures were area under the curves (AUCs) and maximum plasma concentration (C max) of EE, and total and unbound GSD (Studies 1 and 2). AUC and C max of midazolam (Study 3). Co-administration of CYP3A4 inhibitors did not affect EE metabolism, and had only weak effects on the PK of total and unbound GSD. The patch had no clinically relevant effect on metabolism of the CYP3A4 substrate midazolam.

This study compares the efficacy of a levonorgestrel-releasing intrauterine system (LNG-IUS) and a low-dose combined oral contraceptive (COC) in reducing adenomyosis-related pain and bleeding.

A randomized clinical trial included 62 participants complaining of pain and bleeding that was associated with adenomyosis. Participants were randomly assigned to either LNG-IUS or COC treatment. The outcomes included the improvement of pain using a visual analogue scale, menstrual blood loss using a menstrual diary and estimated uterine volume by ultrasound for 6 months of treatment. We also compared uterine arteries and intramyometrial Doppler indices before and 6 months after treatment with both LNG-IUS and COCs.

Both treatments significantly reduced pain after 6 months of use; however, the reduction was greater in the LNG-IUS group (from 6.23±0.67 to 1.68±1.25) compared with the COCs group (from 6.55±0.68 to 3.90±0.54). Both treatment arms significantly decreased the number of bleeding days, uterine volume and Doppler blood flow in the uterus from before to after treatment. These effects were more significant in the LNG-IUS arm compared with the COC arm.

Both LNG-IUS and COCs decreased the pain and menstrual bleeding that is associated with adenomyosis. However, LNG-IUS is more effective than the COCs in reducing pain and menstrual blood loss. This effect may be secondary to the decrease in uterine volume and the increase in blood flow resistance.