STUDY QUESTION: Is it feasible to deliver @entity13558 ( @entity10664 ), an aromatase inhibitor (AI), by a vaginal polymer-based drug delivery system in the @entity5434 ( @entity5434 ) to describe the pharmacokinetic profile? SUMMARY ANSWER: The present study showed the effective release of @entity10664 into the systemic circulation from intravaginal rings in @entity5434 . WHAT IS KNOWN ALREADY: @entity10664 is a marketed drug with well documented pharmacological and safety profiles for oral administration. Aromatase is the key enzyme catalyzing @entity172 biosynthesis and is overexpressed in endometriotic lesions. AIs show therapeutic efficacy in @entity46 in exploratory clinical trials. STUDY DESIGN, SIZE, DURATION: The pharmacokinetics of the in vivo release and the pharmacodynamic activity of @entity10664 released by intravaginal rings (IVR) were investigated in healthy cycling female @entity5434 in three different dose groups (n = 5) for one menstrual cycle. @entity1 /MATERIALS, SETTING, METHODS: IVRs for the @entity5434 , releasing three different doses of @entity10664 were designed and tested for in vitro/in vivo release for up to 42 days. For pharmacokinetic and pharmacodynamic evaluation, plasma samples were taken once daily from Day 1 to 3 and then every third day until menses occurred (17-42 days). MAIN RESULTS AND THE ROLE OF CHANCE: @entity10664 was shown to be compatible with the IVR drug delivery system. An average in vivo release of 277   g/day/animal of @entity10664 for one menstrual cycle was effective in causing a decrease of systemic @entity53 (E2) levels by    30% without inducing counter regulation such as the elevation of FSH or the formation of @entity42 . LIMITATIONS, REASONS FOR CAUTION: The study was limited to three dose groups in which only the highest dose decreased the E2 level. Hence, additional research with IVRs releasing higher amounts of @entity10664 is required to define the threshold for an @entity10664 -dependent ovarian stimulation in @entity5434 . WIDER IMPLICATIONS OF THE FINDINGS: The release rate administered from IVRs is sufficient and in a range that supports feasibility of IVR administration of @entity10664 as a new approach for long-term therapy of @entity172 -dependent diseases such as @entity46 in @entity1 . STUDY FUNDING/COMPETING INTERESTS: No research funding was received and none of the authors have any conflict of interests.

Characterization of XXXX effects, delivered by an intravaginal ring in @entity5434 .

@entity172 :: ('MESH:D004967', 'Chemical') :: ['estrogen'] @entity1 :: ('9606', 'Species') :: ['human', 'PARTICIPANTS'] @entity10664 :: ('CHEBI:37924', 'Chemical') :: ['ATZ'] @entity5434 :: ('9541', 'Species') :: ['Macaca fascicularis', 'cynomolgus monkey', 'cynomolgus monkeys'] @entity53 :: ('MESH:D004958', 'Chemical') :: ['estradiol'] @entity42 :: ('MESH:D010048', 'Disease') :: ['ovarian cysts'] @entity46 :: ('MESH:D004715', 'Disease') :: ['endometriosis'] @entity13558 :: ('MESH:C090450', 'Chemical') :: ['anastrozole']
@entity13558 :: (MESH:C090450,Chemical) :: ['anastrozole']
