Safety and Efficacy of Telapristone Acetate (Proellex®) in the Treatment of Pre-Menopausal Women With Confirmed, Symptomatic Endometriosis

Inclusion Criteria

• Adult females between 18 and 47 years of age using prescription analgesics for endometriosis pain and with a Biberoglu Behrman Symptom Severity Scale (BBSS) score ≥7 at screening (assessed over the previous 28 days).
• Endometriosis diagnosis must have been surgically confirmed within 7 years. A laparoscopic diagnosis is acceptable.
• Participants must have a history of at least 3 regular menstrual cycles in which symptoms of endometriosis occurred immediately prior to screening.
• Normal or abnormal but non-clinically significant transvaginal ultrasound.
• History of menstrual events occurring in regular cycles.
• Agreement not to attempt to become pregnant during the trial.
• Agreement to limit alcohol consumption to no more than 2 drinks per week and to avoid alcohol consumption within 48 hours before each visit.
• Ability to complete a daily electronic participant diary and study procedures in compliance with the protocol.
• Women of child-bearing potential must be willing to use double-barrier contraception during the study and for 30 days after discontinuation of study medication. Acceptable double-barrier methods are: male condom with spermicide; male condom with diaphragm; diaphragm containing spermicide plus additional intra-vaginal spermicide.
• Has a negative pregnancy test at the Screening and Baseline visits, and subsequent study visits.
• A Body Mass Index (BMI) between 18 and 39 inclusive.
• Is available for all treatment and follow-up visits.

Exclusion Criteria

• Post-menopausal woman, defined as either; six (6) months or more (immediately prior to screening visit) without a menstrual period, or prior hysterectomy and/or oophorectomy.
• Pregnant or lactating or is attempting or expecting to become pregnant during the 6-7 month study period.
• Women with abnormally high liver enzymes or liver disease [alanine transaminase (ALT) or aspartate aminotransferase (AST) exceeding 2 x upper limit of normal (ULN) and total bilirubin exceeding 1.5 x ULN at screening and confirmed on repeat].
• Received an investigational drug in the 30 days prior to the screening for this study.
• History of polycystic ovary syndrome (PCOS).
• Concurrent use of any testosterone, androgen, anabolic steroids, dehydroepiandrosterone (DHEA) or hormonal products for at least 2 weeks prior to screening and during the study. Oral contraceptive use for control of endometriosis symptoms is acceptable for the first 28-days of the study.
• Use of Depo-Provera® in the preceding 6 months.
• Use of Gonadotrophin releasing hormone (GnRH) as (e.g. Lupron Depot) within 3 months of the first dose of study drug (Lupron Depot must have a wash-out period of 3 months after the period of duration of the Lupron dose).
• Has an intrauterine device (IUD) in place. Copper IUDs (non-hormone containing will be permitted).
• Presence of intramural fibroids that impact the endometrial stripe, submucosal fibroids (any size), or endometrial polyps. Subserosal and intramural fibroids with no impact on the endometrial stripe are acceptable.
• Presence of endometrioma(s).
• Present history or condition that causes non-endometriosis related dyspareunia (e.g. vulvar vestibulitis).
• Past or present history of thrombophlebitis or thromboembolic disorders.
• Known or suspected carcinoma of the breast or reproductive organs.
• History of abnormal electrocardiogram (ECG) that, in the opinion of the investigator, is clinically significant and will prevent the participant from completing the study, including a QTc (corrected QT interval) of greater than 450 milliseconds (ms).
• Cervical dysplasia classified as Atypical Squamous Cells of Undetermined Significance (ASCUS) associated with high-risk human papilloma virus (HPV) or Low/High Grade Squamous Intraepithelial Lesion (LGSIL or HGSIL).
• History of abnormal endometrial biopsy including the presence of Endometrial Intraepithelial Neoplasia (EIN).
• Recent history (within past 6 months) of alcoholism or