Endometriosis

- Signed and dated informed consent
- Pre-menopausal women 18 years (inclusive) and above at the time of Visit 1
- Women with endometriosis confirmed by laparoscopy or laparotomy OR diagnosed based on imaging
- Moderate to severe endometriosis-associated pelvic pain (EAPP)
- Adherence to screening period diary entries
- Willingness to use only standardized pain medication if needed
- Good general health (except for findings related to endometriosis)
- Normal or clinically insignificant cervical cytology not requiring further follow-up
- An endometrial biopsy performed at the screening phase without significant histological disorder
- Use of an acceptable non-hormonal method of contraception
- Willingness / ability to comply with electronic diary entry for the duration of study participation

- Pregnancy or lactation (less than 3 months since delivery, abortion, or lactation before Visit 1)
- Hypersensitivity to any ingredient of the study treatments
- Laboratory values outside the inclusion range before randomization, and considered clinically relevant
- Any diseases or conditions that can compromise the function of the body systems and could result in altered absorption, excessive accumulation, impaired metabolism, or altered excretion of the study drug including elevated liver enzymes
- Any diseases or conditions that might interfere with the conduct of the study or the interpretation of the results
- Undiagnosed abnormal genital bleeding
- Abuse of alcohol, drugs, or medicines (e.g. laxatives) as evaluated by the investigator
- Use of other treatments that might interfere with the conduct of the study or the interpretation of the results
- Endometriosis-specific treatments for symptom relief except rescue pain medication according to protocol
- Simultaneous participation in another clinical trial with investigational medicinal product(s). Participation in another trial prior to study entry that might have an impact on the study objectives, at the discretion of the investigator
- Inability to cooperate with the study procedures for any reason
- Previous assignment to treatment (e.g. randomization) during this study (allowing previously randomized subjects to be re-included into the study may lead to bias)
- Hypersensitivity to any ingredient of standardized pain medication
- Wish for pregnancy during the study
- Regular use of pain medication due to other underlying diseases
- Non-responsiveness of EAPP to GnRH-a (Gonadotropin-releasing hormone agonists)