NCT07570316 · argenx
A Study to Assess Efficacy and Safety of Efgartigimod PH20 SC PFS in Adult Participants With Graves' Disease
(VitaliThy)
What this study is about
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.
View original scientific description
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.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Is at least 18 years of age and the local legal age of consent for clinical studies when signing the ICF.
- Has a documented diagnosis of GD with TRAb (anti-thyrotropin receptor antibody) levels \>=ULN (upper limit of normal) at screening.
- Has active hyperthyroidism due to GD with TSH (thyroid-stimulating hormone) \<0.1 mIU/L at screening.
- Has been treated with MMI (methimazole) or CBZ (carbimazole) for at least 3 months before screening.
Exclusion criteria
- History of hyperthyroidism not caused by GD (eg, toxic adenoma or toxic multinodular goiter).
- History of RAI (radioactive iodine) therapy or received a total thyroidectomy.
- T3- or T4-containing medication or supplement (eg, levothyroxine, liothyronine, desiccated thyroid preparations, or thyroid-support supplements) received \<6 weeks before screening.
- Any complication of hyperthyroidism or underlying medical condition that would put the participant at undue risk. This includes arrhythmia or tachyarrhythmia related to GD, such as atrial fibrillation or atrial flutter not sufficiently controlled with medications.
- Graves' orbitopathy/Thyroid Eye Disease (GO/TED) requiring systemic therapy (eg, corticosteroids), orbital injections, orbital surgery, or orbital radiation, or expected immediate surgical intervention and/or planned corrective surgery/irradiation or medical therapy during the study.
Where
- Orange, California
- Pasadena, California
- Fleming Island, Florida
- Fort Lauderdale, Florida
- Kissimmee, Florida
- Lenexa, Kansas
- Dearborn, Michigan
- Farmington Hills, Michigan
- New York, New York
- Dallas, Texas
- Houston, Texas
- Irving, Texas
And 4 more locations — see the full list below.
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 8, 2026 · Source of record for eligibility and locations