# A Phase 3 Study to Confirm the Efficacy and Safety of Linzagolix to Treat Endometriosis-associated Pain

> **NCT03986944** · PHASE3 · TERMINATED · sponsor: **Kissei Pharmaceutical Co., Ltd.** · enrollment: 85 (actual)

## Conditions studied

- Endometriosis

## Interventions

- **DRUG:** 75 mg linzagolix tablet
- **DRUG:** 200 mg linzagolix tablet
- **DRUG:** Add-back capsule (E2 1 mg / NETA 0.5 mg)
- **DRUG:** Placebo tablet to match 75 mg linzagolix tablet
- **DRUG:** Placebo tablet to match 200 mg linzagolix tablet
- **DRUG:** Placebo capsule to match Add-back capsule

## Key facts

- **NCT ID:** NCT03986944
- **Lead sponsor:** Kissei Pharmaceutical Co., Ltd.
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** TERMINATED
- **Start date:** 2019-05-23
- **Primary completion:** 2021-01-06
- **Final completion:** 2021-02-16
- **Target enrollment:** 85 (ACTUAL)
- **Why stopped:** Study halted due to the significant enrollment challenges encountered since its beginning. Screening and enrollment have been impacted by the COVID pandemic and more importantly by changes in the diagnosis and treatment of women with endometriosis.
- **Last updated:** 2025-04-02


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT03986944

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT03986944, "A Phase 3 Study to Confirm the Efficacy and Safety of Linzagolix to Treat Endometriosis-associated Pain". Retrieved via AI Analytics 2026-06-25 from https://api.ai-analytics.org/clinical/NCT03986944. Licensed CC0.

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