NCT04818671CompletedPhase 3
Evaluating the Long-Term Safety and Tolerability of Efgartigimod PH20 SC Administered Subcutaneously in Patients With Generalized Myasthenia Gravis
A Long-Term, Single-Arm, Open-label, Multicenter Phase 3 Study to Evaluate the Safety and Tolerability of Multiple Subcutaneous Injections of Efgartigimod PH20 SC in Patients With Generalized Myasthenia Gravis
Source: ClinicalTrials.gov · Last updated 22 Jan 2026
Brief summary (registry, in English)
The purpose of this study is to evaluate the long-term safety and tolerability of efgartigimod PH20 SC 1000 mg, and the clinical efficacy, PD, pharmacokinetics (PK), immunogenicity, impact on the quality of life (QoL) of the participants, treatment satisfaction, and administration method preference, and the feasibility of self- and caregiver-supported administration of the SC injection. Treatment duration: 3-week treatment periods, repeated as needed with at least 28 days in between treatment periods Health measurements: total levels of immunoglobulin G (IgG), Acetylcholine receptor binding autoantibodies (AChR-Ab) levels, Myasthenia Gravis Activities of Daly Living (MG-ADL).
- Status (registry)
- Completed
- Phase (registry)
- Phase 3
- Study type
- Interventional
- Enrollment
- 184 (actual)
- First submitted
- 11 Mar 2021
- Start date
- 26 Apr 2021
- Primary completion date
- 31 Dec 2024
- Lead sponsor
- argenx
- Diseases
- Myasthenia gravis
- NCT number
- NCT04818671
What you commit to
- Study type: Interventional · Phase 3
- Participants enrolled: 184
- From 26 Apr 2021 to the primary completion date, 31 Dec 2024
- 47 sites in 12 countries
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Received a live-attenuated vaccine within 28 days prior to study entry or plan to receive a live-attenuated vaccine during the study
Other illness
- A known hypersensitivity reaction to efgartigimod, rHuPH20, or any of its excipients
Age
- Has any of the following medical conditions:
- Clinically significant uncontrolled chronic bacterial, viral, or fungal infection at roll-over
- Any other known autoimmune disease that, in the opinion of the investigator, would interfere with accurate assessment of clinical symptoms of myasthenia gravis or put the participant at undue risk
- History of malignancy unless deemed cured by adequate treatment with no evidence of reoccurrence for ≥3 years before the first administration of investigational medicinal product (IMP).
- Participants with the following cancers can be included at any time:
- adequately treated basal cell or squamous cell skin cancer
- carcinoma in situ of the cervix
- carcinoma in situ of the breast
- incidental histological findings of prostate cancer (TNM classification of malignant tumors stage T1a or T1b)
- Clinical evidence of other significant serious diseases, or the participant has had a recent major surgery, or who have any other condition that, in the opinion of the investigator, could confound the results of the study or put the participant at undue risk
Other
- The participant was discontinued early from studies ARGX-113-2001 or ARGX-113-1705, unless the reason for discontinuation from study ARGX-113-1705 was to roll over into study ARGX-113-2002.
- Participants who, in the investigator's judgment, are not benefiting from efgartigimod IV in study ARGX-113-1705 Part B are not eligible for roll over into ARGX-113-2002.
- Are pregnant or lactating, or intend to become pregnant during the study or within 90 days after the last dose of investigational medicinal product (IMP)
Who the study is looking for
- Must be capable of giving signed informed consent, which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.
- Previously participated in antecedent studies ARGX-113-2001 or ARGX-113-1705 and are eligible for roll over.
- Contraceptive use by men and women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies and:
- Women of Child bearing potential (WOCBP) must have a negative urine pregnancy test at baseline before investigational medicinal product (IMP) can be administered.
Age in the registry: 18 years to - · Sex: All · Does not accept healthy volunteers
Sites (47)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Investigator site 5 - BE0320007 Coordinator of this site? Confirm its status | Ghent | Belgium | Unknown status |
| Investigator site 24 - CZ4200005 Coordinator of this site? Confirm its status | Brno | Czechia | Unknown status |
| Investigator Site 25 - DE490006 Coordinator of this site? Confirm its status | Berlin | Germany | Unknown status |
| Investigator Site 26 - DE490009 Coordinator of this site? Confirm its status | Münster | Germany | Unknown status |
| Investigator Site 37 - ES0340021 Coordinator of this site? Confirm its status | Barcelona | Spain | Unknown status |
| Investigator Site 31 - ES0340038 Coordinator of this site? Confirm its status | Barcelona | Spain | Unknown status |
| Investigator site 23 - ES0340039 Coordinator of this site? Confirm its status | Valencia | Spain | Unknown status |
| Investigator Site 32 - GEO9950004 Coordinator of this site? Confirm its status | Tbilisi | Georgia | Unknown status |
| Investigator Site 1 - GEO9950001 Coordinator of this site? Confirm its status | Tbilisi | Georgia | Unknown status |
| Investigator Site 2 - GEO9950002 Coordinator of this site? Confirm its status | Tbilisi | Georgia | Unknown status |
| Investigator Site 33 - GEO9950016 Coordinator of this site? Confirm its status | Tbilisi | Georgia | Unknown status |
| Investigator Site 3 - GEO9950003 Coordinator of this site? Confirm its status | Tbilisi | Georgia | Unknown status |
| Investigator site 10 - HU0360013 Coordinator of this site? Confirm its status | Budapest | Hungary | Unknown status |
| Investigator site 9 - HU0360012 Coordinator of this site? Confirm its status | Budapest | Hungary | Unknown status |
| Investigator site 11 - IT0390003 Coordinator of this site? Confirm its status | Milan | Italy | Unknown status |
| Investigator Site 34 - IT0390007 Coordinator of this site? Confirm its status | Naples | Italy | Unknown status |
| Investigator Site 35 - IT0390008 Coordinator of this site? Confirm its status | Roma | Italy | Unknown status |
| Investigator site 12 - JP0810002 Coordinator of this site? Confirm its status | Chiba | Japan | Unknown status |
| Investigator site 8 - JP0810004 Coordinator of this site? Confirm its status | Hanamaki | Japan | Unknown status |
| Investigator site 14 - JP0810007 Coordinator of this site? Confirm its status | Osaka | Japan | Unknown status |
| Investigator Site 28- JP0810059 Coordinator of this site? Confirm its status | Ōta-ku | Japan | Unknown status |
| Investigator Site 27 - JP0810008 Coordinator of this site? Confirm its status | Sapporo | Japan | Unknown status |
| Investigator Site 36 - JP0810055 Coordinator of this site? Confirm its status | Sapporo | Japan | Unknown status |
| Investigator site 13 - JP0810005 Coordinator of this site? Confirm its status | Sendai | Japan | Unknown status |
| Investigator site 15 - JP0810009 Coordinator of this site? Confirm its status | Tokyo | Japan | Unknown status |
| Investigator site 16 - NL0310001 Coordinator of this site? Confirm its status | Leiden | Netherlands | Unknown status |
| Investigator site 17 - PL0480001 Coordinator of this site? Confirm its status | Gdansk | Poland | Unknown status |
| Investigator site 19 - PL0480007 Coordinator of this site? Confirm its status | Katowice | Poland | Unknown status |
| Investigator site 18 - PL0480005 Coordinator of this site? Confirm its status | Krakow | Poland | Unknown status |
| Investigator site 22 - PL0480065 Coordinator of this site? Confirm its status | Krakow | Poland | Unknown status |
| Investigator site 20 - PL0480018 Coordinator of this site? Confirm its status | Lublin | Poland | Unknown status |
| Investigator site 21 - PL0480022 Coordinator of this site? Confirm its status | Warsaw | Poland | Unknown status |
| Investigator Site 29- RU0070002 Coordinator of this site? Confirm its status | Novosibirsk | Russia | Unknown status |
| Investigator Site 30 - RU0070014 Coordinator of this site? Confirm its status | Saint Petersburg | Russia | Unknown status |
| Investigator Site 46 - US0010111 Coordinator of this site? Confirm its status | Amherst | United States | Unknown status |
| Investigator Site 43 - US0010066 Coordinator of this site? Confirm its status | Austin | United States | Unknown status |
| Investigator Site 45 - US0010108 Coordinator of this site? Confirm its status | Boca Raton | United States | Unknown status |
| Investigator site 6 - US0010032 Coordinator of this site? Confirm its status | Carlsbad | United States | Unknown status |
| Investigator Site 38 - US0010003 Coordinator of this site? Confirm its status | Chapel Hill | United States | Unknown status |
| Investigator Site 42 - US0010019 Coordinator of this site? Confirm its status | Cleveland | United States | Unknown status |
| Investigator site 7 - US0010008 Coordinator of this site? Confirm its status | Cordova | United States | Unknown status |
| Investigator Site 44 - US0010077 Coordinator of this site? Confirm its status | Durham | United States | Unknown status |
| Investigator Site 41 - US0010015 Coordinator of this site? Confirm its status | Kansas City | United States | Unknown status |
| Investigator Site 47 - US0010021 Coordinator of this site? Confirm its status | Palo Alto | United States | Unknown status |
| Investigator site 4 - US0010110 Coordinator of this site? Confirm its status | Port Charlotte | United States | Unknown status |
| Investigator Site 40 - US0010009 Coordinator of this site? Confirm its status | San Antonio | United States | Unknown status |
| Investigator Site 39 - US0010006 Coordinator of this site? Confirm its status | Tampa | United States | Unknown status |
This page is information, not medical advice. Discuss any trial with your doctor.