Letrozole in the Treatment of Severe and Recurrent Endometriosis

Study Overview
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Brief Summary
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Endometriosis is a condition in which abnormal growth of tissue histologically resembling the lining of the uterus (endometrium) is present outside of the uterus. This study will investigate the effect of a daily dose of letrozole compared to GnRH is safe and in addition effective in reducing measurable endometriosis lesions and in reducing pain in patients with active endometriosis which were pretreated with GnRH analogs for 2 months.

Official Title
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Letrozole in the Treatment of Severe and Recurrent Endometriosis

Conditions
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Severe and Recurrent Endometriosis

Intervention / Treatment
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* Drug: Letrozole


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Premenopausal women > 18 years of age. Laparoscopic and Histologically confirmed diagnosis of moderate or severe endometriosis according rASRM-Score III and IV BMI less than 40 kg/m². Patient is sexually abstinent or using mechanical (condoms, diaphragms) or sterilization methods of contraception and is willing to continue using them throughout the study. Patient is willing and able to comply with study requirements. Written informed consent. Exclusion Criteria Endometriosis stage I-II acc. according to rASRM Women with other causes of chronic pelvic pain including infectious, gastrointestinal, musculoskeletal, neurologic or psychiatric. Significant abnormalities in the physical or laboratory examination including renal and liver function more than twice the normal range. Patient desires pregnancy for the duration of the study, is pregnant or breast feeding. GnRH therapy during the last 6 months Use of hormonal contraception, selective estrogen receptor modulators, progestins, estrogens, steroids, or ovulation induction in the 4 weeks prior to inclusion into the study. Untreated abnormal pap smear or other gynecologic condition. History of venous thrombosis events including deep vein thrombosis, pulmonary embolism, or retinal vein thrombosis. History of stroke, complicated migraine, or documented transient ischemic attack. Known hypersensitivity to any ingredient of the study medication. Treatment with other aromatase inhibitors Other investigational drugs within the past 30 days and the concomitant use of investigational drugs. History of non-compliance to medical regimens, and patients who are considered potentially unreliable. Additional protocol-defined inclusion / exclusion criteria may apply

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: Letrozole|nan|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Response rates (CR, PR, NC, PD) during treatment of advanced endometrial cancer assessed by tumor marker assessments and radiologic imaging at week 12 then q 12 weeks x 1 year then q 16 weeks |  |  | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of clinical response |  |  | 
| Time to progression of the disease |  |  | 
| Correlation of tumour response with pretreatment ER/PR status |  |  | 
| Histological grade and aromatase levels |  |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Endometriosis, GnRH analog, Aromataseinhibitor, Letrozole