A Phase 3 interventional study of 75 mg linzagolix tablet and 200 mg linzagolix tablet in Endometriosis, sponsored by Kissei Pharmaceutical Co., Ltd.. Completed at 71 sites in 10 countries. Open to female participants aged 18 Years to 49 Years. Per ClinicalTrials.gov, last updated 2025-04-02.
Sponsored by Kissei Pharmaceutical Co., Ltd. · Phase 3, Interventional, and Treatment
The primary objective of this study is to demonstrate the efficacy and safety of linzagolix administered orally once daily for 3 months at a dose of 75 mg alone or of 200 mg in combination with add-back hormone replacement therapy (ABT: estradiol (E2) 1 mg / norethisterone acetate (NETA) 0.5 mg) versus placebo, in the management of moderate to severe endometriosis-associated pain (EAP).
This is a prospective, randomized, double-blind, placebo-controlled study to demonstrate the efficacy and safety of linzagolix administered orally once daily at doses of 75 mg alone and 200 mg in combination with low dose ABT (E2 1 mg/NETA 0.5 mg) versus placebo in the management of moderate to severe EAP in 450 women.
Eligible subjects who have completed the 6-month treatment period may enter a separate extension study for 6 additional months of active treatment (no placebo control). Subjects who do not continue in the extension study will enter a 6 month treatment-free follow-up phase.
901 studies on the registry are indexed under Endometriosis; 259 are open to participants now.
This study's enrollment of 486 is above the median of 64 across 525 interventional studies indexed under Endometriosis.
Browse Endometriosis studies →Kissei Pharmaceutical Co., Ltd. is the lead sponsor of 61 studies on the registry; 3 are open to participants now.
Counted across the registry records on this site, refreshed daily.
The subject must have:
Exclusion Criteria:
The subject will be excluded if she:
Drug: 75 mg linzagolix tablet · Drug: Placebo tablet to match 200 mg linzagolix tablet · Drug: Placebo capsule to match Add-back capsule
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 75 mg linzagolix tablet · Drug: Placebo tablet to match 200 mg linzagolix tablet · Drug: Placebo capsule to match Add-back capsule
For oral administration once daily
For oral administration once daily
For oral administration once daily
For oral administration once daily
For oral administration once daily
For oral administration once daily
Reduction of Dysmenorrhea (DYS) at Month 3 - Proportion of Responders
Percentage of subjects with reduction of 1.1 for DYS in mean pelvic pain score within last 28 days prior to Month 3 or discontinuation, and stable or decreased use of analgesics for Endometriosis-associated pain (=EAP) within the same calendar days.
Time frame: Baseline to Month 3
Reduction of Non-menstrual Pelvic Pain (NMPP) at Month 3 - Proportion of Responders
Percentage of subjects with reduction of 0.8 for NMPP in mean pelvic pain score within last 28 days prior to Month 3 or discontinuation, and stable or decreased use of analgesics for Endometriosis-associated pain (=EAP) within the same calendar days.
Time frame: Baseline to Month 3
Of the 854 subjects screened, 486 were randomized. Between randomization and Day 1 (i.e., first day of dosing), 2 subjects in the LGX 75 mg group discontinued due to protocol deviation. Thus, 484 randomized subjects were treated and comprised the FAS and SAF.
| Milestone | LGX 75 mg | LGX 200 mg+ABT | Placebo |
|---|---|---|---|
| Started | 160 | 162 | 162 |
| Month 3 | 149 | 155 | 149 |
| Month 6 | 140 | 143 | 137 |
| Completed | 140 | 143 | 137 |
| Not completed | 20 | 19 | 25 |
| Withdrew: Adverse event | 8 | 6 | 3 |
| Withdrew: Lost to follow-up | 0 | 1 | 1 |
| Withdrew: Pregnancy | 2 | 0 | 1 |
| Withdrew: Protocol violation | 1 | 2 | 0 |
| Withdrew: Withdrawal by subject | 8 | 10 | 20 |
| Withdrew: Sponsor decided to exclude the patient | 1 | 0 | 0 |
Percentage of subjects with reduction of 1.1 for DYS in mean pelvic pain score within last 28 days prior to Month 3 or discontinuation, and stable or decreased use of analgesics for Endometriosis-associated pain (=EAP) within the same calendar days.
| Percentage of responders | LGX 75 mg | LGX 200 mg+ABT | Placebo |
|---|---|---|---|
| Reduction of Dysmenorrhea (DYS) at Month 3 - Proportion of Responders | 44.0 (36.3 to 52.0) | 72.9 (65.3 to 79.4) | 23.5 (17.5 to 30.7) |
Percentage of subjects with reduction of 0.8 for NMPP in mean pelvic pain score within last 28 days prior to Month 3 or discontinuation, and stable or decreased use of analgesics for Endometriosis-associated pain (=EAP) within the same calendar days.
| Percentage of responders | LGX 75 mg | LGX 200 mg+ABT | Placebo |
|---|---|---|---|
| Reduction of Non-menstrual Pelvic Pain (NMPP) at Month 3 - Proportion of Responders | 38.9 (31.5 to 46.9) | 47.3 (39.5 to 55.3) | 30.9 (24.1 to 38.6) |
Collected over Day 1 to Month 6 of the treatment period. Non-serious events are listed at a 3% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| LGX 75 mg | 0/160 (0%) | 1/160 (0.6%) | 83/160 (51.9%) |
| LGX 200 mg+ABT | 0/162 (0%) | 2/162 (1.2%) | 94/162 (58%) |
| Placebo | 0/162 (0%) | 0/162 (0%) | 69/162 (42.6%) |
| Event | LGX 75 mg | LGX 200 mg+ABT | Placebo |
|---|---|---|---|
| EndometriosisReproductive system and breast disorders | 1/160 | 0/162 | 0/162 |
| PeritonitisInfections and infestations | 1/160 | 0/162 | 0/162 |
| PneumoniaInfections and infestations | 0/160 | 1/162 | 0/162 |
| Abdominal painGastrointestinal disorders | 0/160 | 1/162 | 0/162 |
| Event | LGX 75 mg | LGX 200 mg+ABT | Placebo |
|---|---|---|---|
| HeadacheNervous system disorders | 13/160 | 17/162 | 13/162 |
| Hot flushVascular disorders | 12/160 | 11/162 | 4/162 |
| FatigueGeneral disorders | 6/160 | 11/162 | 4/162 |
| AnaemiaBlood and lymphatic system disorders | 5/160 | 4/162 | 10/162 |
| Mood swingsPsychiatric disorders | 8/160 | 5/162 | 3/162 |
| ArthralgiaMusculoskeletal and connective tissue disorders | 8/160 | 3/162 | 2/162 |
| NauseaGastrointestinal disorders | 6/160 | 6/162 | 7/162 |
| Urinary tract infectionInfections and infestations | 3/160 | 7/162 | 0/162 |
| Abdominal distensionGastrointestinal disorders | 4/160 | 6/162 | 3/162 |
| Vaginal haemorrhageReproductive system and breast disorders | 4/160 | 6/162 | 1/162 |
| Age, Categorical(Participants) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| <=18 years | 0 | 0 | 0 | 0 |
| Between 18 and 65 years | 160 | 162 | 162 | 484 |
| >=65 years | 0 | 0 | 0 | 0 |
| Age, Continuous(Years) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| Mean | 35.1 ± 6.4 | 34.6 ± 6.8 | 34.9 ± 6.8 | 34.9 ± 6.6 |
| Age, Customized(Years) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| Median | 35.5 (31.0 to 40.0) | 35.0 (30.0 to 40.0) | 35.0 (31.0 to 40.0) | 35.0 (30.0 to 40.0) |
| Sex: Female, Male(Participants) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| Female | 160 | 162 | 162 | 484 |
| Male | 0 | 0 | 0 | 0 |
| Ethnicity (NIH/OMB)(Participants) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| Hispanic or Latino | 5 | 7 | 1 | 13 |
| Not Hispanic or Latino | 155 | 155 | 161 | 471 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 |
| Race (NIH/OMB)(Participants) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| American Indian or Alaska Native | 0 | 1 | 0 | 1 |
| Asian | 1 | 0 | 0 | 1 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 | 0 |
| Black or African American | 1 | 1 | 2 | 4 |
| White | 158 | 159 | 160 | 477 |
| More than one race | 0 | 1 | 0 | 1 |
| Unknown or Not Reported | 0 | 0 | 0 | 0 |
| Region of Enrollment(Participants) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| Austria | 0 | 0 | 1 | 1 |
| Romania | 18 | 12 | 19 | 49 |
| Hungary | 0 | 0 | 2 | 2 |
| United States | 7 | 12 | 7 | 26 |
| Czechia | 2 | 3 | 1 | 6 |
| Ukraine | 70 | 63 | 70 | 203 |
| Poland | 58 | 64 | 57 | 179 |
| Bulgaria | 4 | 5 | 4 | 13 |
| France | 0 | 1 | 0 | 1 |
| Spain | 1 | 2 | 1 | 4 |
| Weight(kg) | LGX 75 mg | LGX 200 mg+ABT | Placebo | Total |
|---|---|---|---|---|
| Mean | 67.73 ± 14.45 | 65.75 ± 14.75 | 65.81 ± 11.96 | 66.42 ± 13.77 |
1 further baseline measures are reported on the registry.
Documents are hosted by the registry — open the source record to download them.
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This study is completed, as verified in Jun 2022. You cannot join it, but the record below documents what was studied.
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Kissei Pharmaceutical Co., Ltd.