A Study to Assess Efficacy and Safety of Efgartigimod PH20 SC PFS in Adult Participants With Graves' Disease

Conditions

• Graves Disease
• Graves' Disease

Eligibility Criteria

Sex

ALL

Age

18 Years - N/A

Healthy Volunteers

Not accepted

Interventions

• Efgartigimod PH20 SC — BIOLOGICAL
  Subcutaneous injection of Efgartigimod PH20 Via Prefilled Syringe (PFS)
• Placebo PH20 SC — OTHER
  Subcutaneous injection of placebo PH20 via Prefilled Syringe (PFS)

Study Details

The main purpose of this study is to look at how efgartigimod affects thyroid function in adults with Graves' Disease (GD). The study will also check whether efgartigimod is safe and well tolerated. It will look at how efgartigimod is distributed and eliminated in the body, how it changes antibody levels, and how the immune system responds to it. The study consists of a part A double-blinded treatment period, a part B treatment/observation period and a part C open-label treatment/observation period. During the part A and part B treatment periods, participants will receive efgartigimod PH20 SC via Prefilled Syringe (PFS) or placebo. During the part C open-label treatment period, participants will receive efgartigimod PH20 SC PFS. Participation in the different parts of the study will depend on the participant's response to treatment. The total study duration for participants ranges from 63 to 135 weeks, depending on the response to treatment. More information can be found here: https://clinicaltrials.argenx.com/vitalithy

Key Dates

First listed

May 6, 2026

Start date

Jun 10, 2026

Status verified

Jul 2026

Primary completion

Jun 30, 2028

Completion

May 31, 2030

Study Design

Enrollment

230 participants (estimated)

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Arms

• Experimental: Part A - efgartigimod PH20 SC PFS
  Participants will receive efgartigimod PH20 SC Via Prefilled Syringe (PFS) during the part A double-blinded treatment period.
• Placebo Comparator: Part A - placebo PH20 SC PFS
  Participants will receive placebo PH20 SC Via Prefilled Syringe (PFS) during the part A double-blinded treatment period.
• Experimental: Part B - efgartigimod PH20 SC PFS
  Participants will receive efgartigimod PH20 SC Via Prefilled Syringe (PFS) during the part B treatment period.
• Experimental: Part B - placebo PH20 SC PFS
  Participants will receive placebo PH20 SC Via Prefilled Syringe (PFS) during the part B treatment period.
• Experimental: Part C - efgartigimod PH20 SC PFS
  Participants will receive efgartigimod PH20 SC PFS in the part C open-label treatment period

Primary Outcome Measure

Percentage of participants who are euthyroid (fT3, fT4, and TSH within normal ranges) off ATDs at week 24 in part A [ Time Frame: Up to 24 weeks (part A) ]

Central Contacts

• Sabine Coppieters, MD
  857-350-4834
  [email protected]

Locations (16)

Find similar trials in Orange, CA

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