Efficacy, safety and tolerability of the CCR1 antagonist BAY 86-5047 for the treatment of endometriosis-associated pelvic pain: a randomized controlled trial.

INTRODUCTION: Antagonism of CC chemokine receptor type 1 (CCR1) may provide a novel treatment approach for women with symptomatic endometriosis. Studies of CCR1 antagonists in these patients have not been reported. MATERIAL AND METHODS: Women (n = 110; 18-45 years) with symptomatic endometriosis were randomized to BAY 86-5047 or placebo for 12 weeks. Pelvic pain was assessed using the visual analogue scale (VAS) and women recorded the intake of pain medication in a diary. The primary efficacy outcome was a composite of the absolute change in VAS score and the cumulative change in consumption of analgesics between baseline and the end of treatment. Safety assessments included adverse events, blood and urine evaluation and electrocardiography. RESULTS: Mean VAS scores decreased from 64.8 mm at baseline to 49.2 mm at week 12 in the BAY 86-5047 group and from 67.2 mm to 47.8 mm in the placebo group. The proportion of women using analgesics decreased from 33.9% to 11.5% or from 44.4% to 15.4% for patients who received BAY 86-5047 or placebo, respectively. There was no significant difference between the two treatment groups in terms of change in VAS scores (p = 0.45) or intake of analgesics (p = 0.82). A three-step sensitivity analysis failed to show superiority of BAY 86-5047 over placebo (p = 0.67). BAY 86-5047 was well tolerated and no significant safety concerns arose during the study. CONCLUSIONS: Based on these results, BAY 86-5047 is unlikely to be useful in the treatment of women with endometriosis-associated pelvic pain.

Characterization of anastrozole effects, delivered by an intravaginal ring in cynomolgus monkeys.

STUDY QUESTION: Is it feasible to deliver anastrozole (ATZ), an aromatase inhibitor (AI), by a vaginal polymer-based drug delivery system in the cynomolgus monkey (Macaca fascicularis) to describe the pharmacokinetic profile? SUMMARY ANSWER: The present study showed the effective release of ATZ into the systemic circulation from intravaginal rings in cynomolgus monkeys. WHAT IS KNOWN ALREADY: ATZ is a marketed drug with well documented pharmacological and safety profiles for oral administration. Aromatase is the key enzyme catalyzing estrogen biosynthesis and is overexpressed in endometriotic lesions. AIs show therapeutic efficacy in endometriosis in exploratory clinical trials. STUDY DESIGN, SIZE, DURATION: The pharmacokinetics of the in vivo release and the pharmacodynamic activity of ATZ released by intravaginal rings (IVR) were investigated in healthy cycling female cynomolgus monkeys in three different dose groups (n = 5) for one menstrual cycle. PARTICIPANTS/MATERIALS, SETTING, METHODS: IVRs for the cynomolgus monkey, releasing three different doses of ATZ 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: ATZ was shown to be compatible with the IVR drug delivery system. An average in vivo release of 277 µg/day/animal of ATZ for one menstrual cycle was effective in causing a decrease of systemic estradiol (E2) levels by ∼30% without inducing counter regulation such as the elevation of FSH or the formation of ovarian cysts. 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 ATZ is required to define the threshold for an ATZ-dependent ovarian stimulation in cynomolgus monkeys. WIDER IMPLICATIONS OF THE FINDINGS: The release rate administered from IVRs is sufficient and in a range that supports feasibility of IVR administration of ATZ as a new approach for long-term therapy of estrogen-dependent diseases such as endometriosis in human.