A Phase 3, Randomized, Double-Masked, Placebo-Controlled, Multicenter Study to Evaluate the Efficacy, Safety, Tolerability, Pharmacokinetics, Pharmacodynamics, and Immunogenicity of Efgartigimod PH20 SC Administered by Prefilled Syringe in Adult Participants With Thyroid Eye Disease

Status

Completed

Phases

Phase 3

Study type

Interventional

Source

EU CTIS

Registry ID

CTIS2023-509197-35-00

Acronym

ARGX-113-2301

Enrollment

Registered

2024-09-23

Start date

2024-10-17

Completion date

2025-12-15

Last updated

2025-12-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Thyroid Eye Disease (TED)

Brief summary

Percentage of participants who were proptosis responders at week 24 of the Double-Blind treatment period (DBTP).

Detailed description

Change in proptosis measurement in the study eye from baseline to week 24 of the Double-Blind Treatment Period (DBTP), Change in the total GO-QoL score from baseline to week 24 of the Double-Blind Treatment Period (DBTP), Percentage of participants with a resolution of diplopia (responders) a at week 24 of the Double-Blind Treatment Period (DBTP).

Interventions

DRUGEfgartigimod

DRUGPlacebo for efgartigimod

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Design outcomes

Primary

Measure	Time frame
Percentage of participants who were proptosis responders at week 24 of the Double-Blind treatment period (DBTP).	—

Secondary

Measure	Time frame
Change in proptosis measurement in the study eye from baseline to week 24 of the Double-Blind Treatment Period (DBTP), Change in the total GO-QoL score from baseline to week 24 of the Double-Blind Treatment Period (DBTP), Percentage of participants with a resolution of diplopia (responders) a at week 24 of the Double-Blind Treatment Period (DBTP).	—

Countries

Belgium, Bulgaria, Czechia, Estonia, Germany, Greece, Hungary, Italy, Romania, Spain

Outcome results

None listed

Source: EU CTIS · Data processed: Feb 4, 2026