Comparison of CDB-2914 Versus Placebo in the Prevention of Follicular Rupture Post-luteinizing Hormone (LH) Surge

Study Overview
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Brief Summary
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Evaluation of the effect of a single dose of CDB-2914, as compared to placebo, administered after the onset of the LH surge on the outcome of the leading ovary follicle: echographic follicle rupture inhibition of follicle rupture luteal phase progesterone levels anovulatory progesterone levels

Official Title
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A Prospective, Randomized, Double-blind, Cross-Over Study to Compare the Capacity to Prevent Follicular Rupture of CDB-2914 With Placebo, When Administered After the Ovulatory Process Has Been Triggered by the LH Surge

Conditions
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Contraception

Intervention / Treatment
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* Drug: CDB-2914 (ulipristal acetate)
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women of good general health aged 18 - 35 years Not at risk of pregnancy Regular menstrual cycles of 24-35 days duration Not pregnant Intact uterus and ovaries Haemoglobin ≥ 11 g/dl Normal laboratory tests and normal TSH Willing to abstain from any use of hormonal contraception until study completion No current use of hormonal contraception and having had at least one complete menstrual cycle (2 menses) since termination of previous hormonal contraception Had at least one complete menstrual cycle (2 menses) following delivery, miscarriage or induced abortion Able to give voluntary, written informed consent, and agreeing to observe all study requirements for 5 complete menstrual cycles Exclusion Criteria: Current participation in any other trial of an investigational medicine Known hypersensitivity to the ingredients of the test active substances or excipients Suspected hyperplasia or carcinoma of the endometrium Current pregnancy as confirmed by positive serum beta-hCG at screening Desire to get pregnant before the planned end of the study participation Currently breastfeeding Abnormal Pap smear Cancer (past history of any carcinoma or sarcoma) Known or suspected alcoholism or drug abuse Abnormal thyroid status Body mass index > 32 Current use of hormonal contraception Use of hormonal emergency contraception since last menstrual period Severe asthma insufficiently controlled by oral glucocorticoids Hereditary galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br> | Drug: Placebo<br>* single oral dose<br>|
| Active Comparator: CDB-2914<br> | Drug: CDB-2914 (ulipristal acetate)<br>* single oral dose of 30 mg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inhibition of follicular rupture | Inhibition is calculated as the number of subjects exhibiting no dominant follicle rupture, divided by the total number of subjects having received treatment | within 6 days after treatment intake | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Appearance or absence of a corpus luteum |  | during the 6 days following treatment intake | 
| Growth pattern of leading follicle | number of cycles exhibiting atresia (diameter decrease ≥25%), or continued growth (diameter increase ≥25%), or interrupted growth (size remains within ±25% of the follicle size at the time of treatment) |  | 
| Presence or absence of a surge of serum luteinizing hormone (LH) levels | The onset of an LH surge is defined as the occurrence of the first single serum LH value whose level is at least 50% higher than the mean of the last two previous measurements, or higher than the last previous measurement if only one previous LH level is available. |  | 
| Menstrual cycle length in comparison to the subject's reported baseline average cycle length and to her placebo-treated cycle length |  |  | 
| Incidence of intermenstrual bleeding and treatment-emergent adverse events |  |  | 
| Incidence of adverse events and occurrence of abnormal laboratory safety variables in comparison with baseline |  |  | 
| Incidence of ovarian cysts after CDB-2914 treatment |  |  |