The Evaluation of Safety and Efficacy of Proellex in the Treatment of Pre-Menopausal Women With Confirmed, Symptomatic Endometriosis

This study is a phase 2, 3-arm-study with an 18 week active dosing period and an option for
subjects to receive 2 additional 16-week cycles of active treatment at their randomized dose
(6 mg or 12 mg/day). Placebo subjects who elect additional treatment will receive treatment
at 12 mg/day. The treatment dose will remain double-blind. The study will be conducted in 3
stages. In the first stage, women will receive a daily single-blind placebo. This stage will
last as long as it takes to record at least one full menstrual cycle (ovulation until
ovulation).

For stage 2, following the run-in stage, at Visit 3, 60 subjects will be randomized into one
of 3 arms in a 1-1-1 fashion. The start of dosing should commence as soon as possible after
ovulation following the end of the previous menstrual event.

For stage 3, subjects who are eligible to receive additional cycles of treatment and who
elect to continue treatment will be scheduled within a week before the second expected menses
(+/- 2 days), following the off-drug interval. Subjects will receive 2 cycles of treatment
separated by an off-drug interval (ODI), after which they will be followed until menses has
returned.

Inclusion Criteria:

- Healthy adult females between 18 and 47 years of age using prescription analgesics for
endometriosis pain and with a BBSS score ≥7 at screening (assessed over the previous
28 days, see Appendix 2).

- Endometriosis diagnosis must have been surgically confirmed within 7 years. A
laparoscopic diagnosis is acceptable.

- Subjects 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 subject 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:

- Subject is a 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.

- Subject is 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. (ALT (alanine transaminase)
or AST(aspartate aminotransferase ) exceeding 2 x ULN (upper limit of normal) AND
total bilirubin exceeding 1.5x ULN at screening and confirmed on repeat).

- Received an investigational drug in the 30 days prior to the screening for this study

- Women with a history of PCOS(polycystic ovary syndrome)

- Concurrent use of any testosterone, androgen, anabolic steroids,
DHEA(dehydroepiandrosterone) 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 GnRHas (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 IUD(intrauterine device) 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 ECG that, in the opinion of the investigator, is clinically
significant and will prevent the subject from completing the study, including a
QTc(corrected QT interval) of greater than 450 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 EIN(Endometrial
Intraepithelial Neoplasia) .

- Recent history (within past 6 months) of alcoholism or drug abuse.

- Known active infection with HIV, Hepatitis A, B or C.

- Previous history of auto-immune disease and/or positive antinuclear antigen (ANA).

- Endometrial stripe ≥18 mm in thickness at Visit 1.

- Women currently taking cimetidine or spironolactone.

- Clinically significant abnormal findings on screening examination and laboratory
assessments or any condition which in the opinion of the investigator would interfere
with the participant's ability to comply with the study instructions or endanger the
participant if she took part in the study.