Assessment and Prevention of Pain During Ovarian Stimulation in Patients With Endometriosis

NCT04002141 | Completed Phase 2 Results DMC FDA Drug

• 1 other identifier: 18-26544
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Randomized double blinded placebo-controlled trial to evaluate the impact of ovarian hyperstimulation on endometriosis-related symptoms and to evaluate the impact of letrozole use during ovarian hyperstimulation with respect to endometriosis-related symptoms, embryo/egg quality and quantity, and pregnancy rates.

Conditions

Endometriosis; Ovarian Hyperstimulation

Keywords

Endometriosis; Letrozole

Outcome Measures

Primary Outcomes (1)

• Average Delta in Endometriosis Pain Score Pre and Post Stimulation With and Without Use Of Letrozole

  To evaluate how letrozole impacts pain scores throughout controlled ovarian hyperstimulation in patients with endometriosis. Pain scores will be evaluated using a 0-10 visual acuity scale, where 0 is no pain and 10 is the worst imaginable pain. The average delta between pre-stimulation pain score and day of trigger shot pain score will be compared between patients with endometriosis receiving placebo and with endometriosis receiving letrozole.

  Baseline ultrasound (day 2 of menstrual cycle) and day 12 (average day of trigger shot).

Secondary Outcomes (7)

• Average Delta in Endometriosis Pain Score Pre and Post Stimulation of Patients Receiving Placebo Compared to No Endometriosis

  Baseline ultrasound (day 2 of menstrual cycle) and day 12 (average day of trigger shot).

• Comparative Trends in Endometriosis Pain Score Pre and Post Stimulation of Patients With Endometriosis Receiving Either Placebo or Letrozole and Patients Without Endometriosis

  Pre-stimulation through 12 weeks post retrieval. This time span varies per each patient's course of treatment but is typically 14 weeks in tota

• Does Letrozole Impact Egg Quantity in Endometriosis Patients

  Baseline ultrasound (day 2 of menstrual cycle) and day 14 (average day of egg retrieval).

• Follicular Fluid

  Baseline ultrasound (day 2 of menstrual cycle) and day 14 (average day of egg retrieval).

• Pregnancy Outcomes

  Up to 2 years.

Study Arms (3)

Endometriosis Letrozole

EXPERIMENTAL

Participants will be asked to take 5mg letrozole daily throughout their ovarian stimulation and for 2 weeks following retrieval. Participants will be blinded to their randomization to letrozole. Participants will be asked to complete surveys during their stimulation and up to 12 weeks following retrieval to evaluate endometriosis associated symptoms. Specifically, surveys will be administered at baseline ultrasound appointment for controlled ovarian hyperstimulation cycle, the day of trigger shot, 3 weeks following egg retrieval, 6 weeks following egg retrieval and 12 weeks following egg retrieval. There will be a total of 20 participants in this arm.

Drug: Letrozole

Endometriosis Placebo

PLACEBO COMPARATOR

Participants will be asked to take one tablet placebo daily throughout their ovarian stimulation and for 2 weeks following retrieval. Participants will be blinded to their randomization to placebo. Participants will be asked to complete surveys during their stimulation and up to 12 weeks following retrieval to evaluate endometriosis associated symptoms. Specifically, surveys will be administered at baseline ultrasound appointment for controlled ovarian hyperstimulation cycle, the day of trigger shot, 3 weeks following egg retrieval, 6 weeks following egg retrieval and 12 weeks following egg retrieval. There will be a total of 20 participants in this arm.

Drug: Placebo oral tablet

No Endometriosis Control

NO INTERVENTION

Participants will be asked to complete surveys during their ovarian stimulation and up to 12 weeks following retrieval to evaluate symptoms of pelvic pain. Specifically, surveys will be administered at baseline ultrasound appointment for controlled ovarian hyperstimulation cycle, the day of trigger shot, 3 weeks following egg retrieval, 6 weeks following egg retrieval and 12 weeks following egg retrieval. There will be a total of 20 participants in this arm.

Interventions

Placebo oral tablet DRUG

1 tablet oral daily

Endometriosis Placebo

Letrozole DRUG

5mg oral daily

Endometriosis Letrozole

Eligibility Criteria

• Age: 18 Years - 42 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18-42 years
• Planning to undergo controlled ovarian hyperstimulation
• Prior diagnosis of endometriosis by one of the following: (1) surgical diagnosis (2) endometrioma on pelvic ultrasound
• Planning to freeze all retrieved oocytes/embryos prior to transfer

You may not qualify if:

• Hypersensitivity to letrozole
• Any significant concurrent disease, illness, or psychiatric disorder that would compromise patient safety or compliance, interfere with consent, study participation, follow-up, or interpretation of study results

Sponsors & Collaborators

• University of California, San Francisco: lead

Study Sites (1)

UCSF Center for Reproductive Health

San Francisco, California, 94158, United States

Location

MeSH Terms

Conditions

Endometriosis

Interventions

Letrozole

Condition Hierarchy (Ancestors)

Genital Diseases, Female; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Genital Diseases

Intervention Hierarchy (Ancestors)

Nitriles; Organic Chemicals; Triazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Results Point of Contact

• Title: Marcelle Cedars, MD, Director, Division of Reproductive Endocrinology
• Organization: University of California, San Francisco

Marcelle.Cedars@ucsf.edu

(415) 353-7475

Study Officials

• Marcelle I Cedars

  University of California, San Francisco

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 28, 2019
• First Posted: June 28, 2019
• Study Start: September 17, 2019
• Primary Completion: October 1, 2023
• Study Completion: January 1, 2025
• Last Updated: January 28, 2026
• Results First Posted: January 28, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)