Generalized Myasthenia GravisPhase 3ADAPTNCT03669588
An Efficacy and Safety Study of ARGX-113 in Patients With Myasthenia Gravis Who Have Generalized Muscle Weakness
A Phase 3 study testing ARGX-113 in people with Generalized Myasthenia Gravis, run by argenx at 66 sites in 16 countries.
Trial summary
A randomized, double-blind, placebo controlled, multicenter Phase 3 trial to evaluate the efficacy, safety, tolerability, quality of life and impact on normal daily activities of ARGX-113 in patients with gMG. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Generalized Myasthenia Gravis
- What is being tested?
- ARGX-113
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 167 participants
- Where
- 66 sitesin 16 countries
- Study dates
- 22 Aug 2018to 6 Apr 2020
- Phase
- Phase 3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients with the ability to understand the requirements of the trial, provide written informed consent, and comply with the trial protocol procedures.
- Male or female patients aged ≥ 18 years.
- Diagnosis of MG with generalized muscle weakness meeting the clinical criteria for diagnosis of MG as defined by the Myasthenia Gravis Foundation of America (MGFA) class II, III, IVa and IVb.
- Other, more specific inclusion criteria are defined in the protocol
Who cannot join
- Pregnant and lactating women, and those intending to become pregnant during the trial or within 90 days after the last dosing.
- Male patients who are sexually active and do not intend to use effective methods of contraception during the trial or within 90 days after the last dosing or male patients who plan to donate sperm during the trial or within 90 days after the last dosing.
- MGFA Class I and V patients.
- Patients with worsening muscle weakness secondary to concurrent infections or medications.
- Patients with known seropositivity or who test positive for an active viral infection at Screening with:
- Hepatitis B Virus (HBV) (except patients who are seropositive because of HBV vaccination)
Show all 9Show fewer
- Hepatitis C Virus (HCV)
- Human Immunodeficiency Virus (HIV)
- Other, more specific exclusion criteria are further defined in the protocol.
Trial locations and contacts
66 sites in 16 countries.
66 sites in 16 countries
United States25 sites
Investigator Site 58
Aurora, Colorado, 80045
Investigator Site 27
Boston, Massachusetts, 02115
Investigator Site 53
Buffalo, New York, 14202
Investigator Site 66
Carlsbad, California, 92011
Investigator Site 3
Chapel Hill, North Carolina, 27599
Investigator Site 17
Charleston, South Carolina, 29425
Investigator Site 2
Charlottesville, Virginia, 22908
Investigator Site 20
Cleveland, Ohio, 44195
Investigator Site
Cordova, Tennessee, 38018
Investigator Site 48
Detroit, Michigan, 48201
Investigator Site 44
Houston, Texas, 77030
Investigator Site 25
Iowa City, Iowa, 52242
Investigator Site 34
Jacksonville, Florida, 32209
Investigator Site 21
Kansas City, Kansas, 66160
Investigator Site 5
Los Angeles, California, 90033
Investigator Site 49
Los Angeles, California, 90095
Investigator Site 18
Orange, California, 92868
Investigator Site 40
Palo Alto, California, 94304
Investigator Site 29
Phoenix, Arizona, 85018
Investigator Site 9
Portland, Oregon, 97239
Investigator Site 6
San Antonio, Texas, 78229
Investigator Site 59
San Francisco, California, 94115
Investigator Site 16
Seattle, Washington, 98195
Investigator Site 30
Springfield, Illinois, 62702
Investigator Site 4
Tampa, Florida, 33612
Japan9 sites
Investigator Site 42
Chiba, Chiba, 260-8677
Investigator Site 19
Hanamaki, Iwate, 025-0075
Investigator Site 31
Meguro City, Tokyo, 1538515
Investigator Site 41
Minato-Ku, Tokyo, 108-8329
Investigator Site 28
Ōsaka-sayama, Osaka, 5898511
Investigator Site 26
Sapporo, Hokkaido, 0608543
Investigator Site 43
Sendai, Miyagi, 983-8520
Investigator Site 39
Shinjuku-Ku, Tokyo, 160-0023
Investigator Site 50
Suita, Osaka, 565-0871
Poland4 sites
Investigator Site 7
Gdansk, 80-952
Investigator Site 57
Katowice, 40-123
Investigator Site 14
Krakow, 31-505
Investigator Site 23
Warsaw, 02-097
Russia4 sites
Investigator Site 64
Krasnoyarsk, 660037
Investigator Site 62
Nizhny Novgorod, 603126
Investigator Site 65
Novosibirsk, 630087
Investigator Site 60
Samara, 443095
Canada3 sites
Investigator Site 38
Edmonton, Alberta, T6G 2G3
Investigator Site 22
Montreal, Quebec, H3A 2B4
Investigator Site 24
Toronto, Ontario, M5G 2C4
Czechia3 sites
Investigator Site 32
Brno, 62500
Investigator Site 35
Ostrava-Poruba, 70852
Investigator Site 51
Prague, 128 00
Georgia3 sites
Investigator Site 46
Tbilisi, 0112
Investigator Site 45
Tbilisi, 0114
Investigator Site 47
Tbilisi, 0114
Belgium2 sites
Investigator Site 11
Edegem, 2650
Investigator Site 8
Ghent, 9000
Denmark2 sites
Investigator Site 36
Aarhus, 8200
Investigator Site 15
Copenhagen, 2100
France2 sites
Investigator Site 13
Bordeaux, 33076
Investigator Site 52
Marseille, 13385
Hungary2 sites
Investigator Site 55
Budapest, 1204
Investigator Site 54
Szeged, 6725
Italy2 sites
Investigator Site 10
Milan, 20133
Investigator Site 12
Naples, 80131
United Kingdom2 sites
Investigator Site 63
Edgbaston, B15 2TH
Investigator Site 56
Liverpool, L9 7LJ
About this study
Official title: A Randomized, Double-Blind, Placebo-Controlled, Multicenter Phase 3 Trial to Evaluate the Efficacy, Safety and Tolerability of ARGX-113 in Patients With Myasthenia Gravis Having Generalized Muscle Weakness
A randomized, double-blind, placebo controlled, multicenter Phase 3 trial to evaluate the efficacy, safety, tolerability, quality of life and impact on normal daily activities of ARGX-113 in patients with gMG.
- Conditions
- Generalized Myasthenia Gravis
- Being tested
- ARGX-113, Placebo
- Medical subject headings
- Myasthenia Gravis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ARGX-113Biological
Also called efgartigimod
Intravenous administration of ARGX-113
PlaceboBiological
Intravenous administration of placebo
| Study group | Role | What they receive |
|---|---|---|
| ARGX-113 | Experimental | Not described Receives: Biological: ARGX-113 |
| Placebo | Placebo comparator | Not described Receives: Biological: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percentage of MG-ADL Responders During Cycle 1 (C1); Analyzed in the AChR-Ab Seropositive Population
The MG-ADL is an 8-item patient-reported scale to assess MG symptoms and their effects on daily activities. The scale comprises 2 items on daily life activities and 6 items on symptoms. The MG-ADL total score range is 0-24, with higher scores indicative of greater disease severity. A patient was considered an MG-ADL responder during C1 if there was a reduction of ≥2 points on the MG-ADL total score (compared to baseline of C1 [C1B]) for ≥4 consecutive weeks with the first reduction occurring no later than 1 week after the last infusion of IMP in C1.
Measured: Baseline up to Day 63 (end of TC1)
Secondary outcomes (5)
Percentage of Quantitative Myasthenia Gravis (QMG) Responders During C1; Analyzed in the AChR-Ab Seropositive Population
The QMG scale quantifies disease severity based on impairments of body functions and structures as defined by the International Classification of Disability and Health. The QMG scale consists of 13 items that measure endurance or fatigability, and accounts for fluctuations in disease state. The QMG total score range is 0-39, with higher scores indicative of greater disease severity. A patient was considered a QMG responder during C1 if there was a reduction of ≥3-points on the QMG total score (compared to C1B) for ≥4 consecutive weeks with the first reduction occurring no later than 1 week after the last infusion of IMP in C1.
Measured: Baseline up to Day 63 (end of TC1)
Percentage of MG-ADL Responders During C1; Analyzed in the Overall Population
The percentage of MG-ADL responders during C1 in the overall population is reported for this secondary end point; percentage of MG-ADL responders during C1 in the AChR-Ab seropositive population is reported previously as a primary end point.
Measured: Baseline up to Day 63 (end of TC1)
Percentage of Time That Patients Had a Clinically Meaningful Improvement (CMI) in MG-ADL Total Score up to and Including Day 126; Analyzed in the AChR-Ab Seropositive Population
An MG-ADL CMI was defined as a reduction of ≥2 points on the total MG-ADL score compared to study entry baseline (SEB).
Measured: Baseline up to Day 126
Time From Week 4 to Qualify for Retreatment; Analyzed in the AChR-Ab Seropositive Population
Time to qualify for retreatment was defined as time from the Week 4 assessment until the first visit with a <2-point reduction compared to SEB in the MG-ADL total score and MG-ADL total score ≥5 points with >50% of the total score attributable to nonocular symptoms.
Measured: Week 4 up to Day 182 (end of study [EoS])
Percentage of Early MG-ADL Responders During C1; Analyzed in the AChR-Ab Seropositive Population
A patient was considered an early MG-ADL responder during C1 if there was a reduction of ≥2 points on the MG-ADL total score (compared to C1B) for ≥4 consecutive weeks with the first reduction occurring no later than Week 2 (ie, after 1 or maximum 2 infusions of IMP in C1).
Measured: Baseline up to Day 63 (end of TC1)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Sep 2018
- Study start22 Aug 2018
- Primary completion6 Apr 2020
- Study completion6 Apr 2020
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for Generalized Myasthenia GravisStudies of the same condition, open and under way.
- More trials run by argenxThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 167 participants (actual)
Sponsor and investigators
- Lead sponsor
- argenx
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Antonio Guglietta, MD, Study director, argenx
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03669588
- Sponsor's protocol ID
- ARGX-113-1704
- Other IDs
- 2018-002132-25, 2018
- Acronym
- ADAPT
- Status last verified
- Mar 2021
- First submitted
- 6 Sep 2018
- Last updated
- 8 Feb 2022
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
- Expanded access
- Available
Publications
Howard JF Jr, Sacca F, Hoffmann S, Attarian S, De Bleecker JL, Beauchamp J, Brauer E, Kerstens R, Vissing J, Meisel A; ADAPT Study Group. Clinical effectiveness of efgartigimod in a broad population of patients with generalized myasthenia gravis: subgroup analyses from a randomized, double-blind, placebo-controlled, phase 3 trial (ADAPT). J Neurol. 2026 Jun 3;273(6):363. doi: 10.1007/s00415-026-13877-z.
PubMed 42234197Hoffmann S, Zhao S, Callewaert F, Schoppe S, Rozsa C, Spillane J. Post Hoc, Sex-Specific Subgroup Analysis of Efgartigimod in Patients With Generalized Myasthenia Gravis From the ADAPT Trial: A Sex and Gender Equity in Research (SAGER) Guidelines Approach. Muscle Nerve. 2026 Apr;73(4):566-574. doi: 10.1002/mus.70135. Epub 2026 Jan 10.
PubMed 41517964Janssen MF, Dewilde S, Wolfe GI, Muppidi S, Phillips G. Psychometric properties of MG-ADL items and MG-ADL score: An assessment of distributional characteristics, validity and factor structure in two large datasets. J Neurol Sci. 2024 Aug 15;463:123135. doi: 10.1016/j.jns.2024.123135. Epub 2024 Jul 22.
PubMed 39068745Howard JF Jr, Bril V, Vu T, Karam C, Peric S, Margania T, Murai H, Bilinska M, Shakarishvili R, Smilowski M, Guglietta A, Ulrichts P, Vangeneugden T, Utsugisawa K, Verschuuren J, Mantegazza R; ADAPT Investigator Study Group. Safety, efficacy, and tolerability of efgartigimod in patients with generalised myasthenia gravis (ADAPT): a multicentre, randomised, placebo-controlled, phase 3 trial. Lancet Neurol. 2021 Jul;20(7):526-536. doi: 10.1016/S1474-4422(21)00159-9.
PubMed 34146511
Study at a glance
From the registry record, last updated by the sponsor on 8 Feb 2022. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Randomized, Double-Blind, Placebo-Controlled, Multicenter Phase 3 Trial to Evaluate the Efficacy, Safety and Tolerability of ARGX-113 in Patients With Myasthenia Gravis Having Generalized Muscle Weakness
- ClinicalTrials.gov ID
- NCT03669588
- Acronym / sponsor ID
- ADAPT / ARGX-113-1704
- Conditions
- Generalized Myasthenia Gravis
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 167 participants (actual)
- Lead sponsor
- argenxIndustry (pharma, biotech, devices)
- Study start
- 22 Aug 2018 (actual)
- Primary completion
- 6 Apr 2020 (actual)
- Study completion
- 6 Apr 2020 (actual)
- First posted
- 13 Sep 2018 (actual)
- Results
- Posted 8 Feb 2022
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A randomized, double-blind, placebo controlled, multicenter Phase 3 trial to evaluate the efficacy, safety, tolerability, quality of life and impact on normal daily activities of ARGX-113 in patients with gMG.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| ARGX-113 | Experimental | Biological: ARGX-113 |
| Placebo | Placebo comparator | Biological: Placebo |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Patients with the ability to understand the requirements of the trial, provide written informed consent, and comply with the trial protocol procedures.
- Male or female patients aged ≥ 18 years.
- Diagnosis of MG with generalized muscle weakness meeting the clinical criteria for diagnosis of MG as defined by the Myasthenia Gravis Foundation of America (MGFA) class II, III, IVa and IVb.
- Other, more specific inclusion criteria are defined in the protocol
Key exclusion criteria (9 listed)
- Pregnant and lactating women, and those intending to become pregnant during the trial or within 90 days after the last dosing.
- Male patients who are sexually active and do not intend to use effective methods of contraception during the trial or within 90 days after the last dosing or male patients who plan to donate sperm during the trial or within 90 days after the last dosing.
- MGFA Class I and V patients.
- Patients with worsening muscle weakness secondary to concurrent infections or medications.
- Patients with known seropositivity or who test positive for an active viral infection at Screening with:
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ARGX-113Also: efgartigimodIntravenous administration of ARGX-113 | Biological | ARGX-113 |
| PlaceboIntravenous administration of placebo | Biological | Placebo |
Primary outcome
Percentage of MG-ADL Responders During Cycle 1 (C1); Analyzed in the AChR-Ab Seropositive Population
Time frame: Baseline up to Day 63 (end of TC1)
The MG-ADL is an 8-item patient-reported scale to assess MG symptoms and their effects on daily activities. The scale comprises 2 items on daily life activities and 6 items on symptoms. The MG-ADL total score range is 0-24, with higher scores indicative of greater disease severity. A patient was considered an MG-ADL responder during C1 if there was a reduction of ≥2 points on the MG-ADL total score (compared to baseline of C1 [C1B]) for ≥4 consecutive weeks with the first reduction occurring no later than 1 week after the last infusion of IMP in C1.
5 secondary outcomes
Percentage of Quantitative Myasthenia Gravis (QMG) Responders During C1; Analyzed in the AChR-Ab Seropositive Population
Time frame: Baseline up to Day 63 (end of TC1)
Percentage of MG-ADL Responders During C1; Analyzed in the Overall Population
Time frame: Baseline up to Day 63 (end of TC1)
Percentage of Time That Patients Had a Clinically Meaningful Improvement (CMI) in MG-ADL Total Score up to and Including Day 126; Analyzed in the AChR-Ab Seropositive Population
Time frame: Baseline up to Day 126
Time From Week 4 to Qualify for Retreatment; Analyzed in the AChR-Ab Seropositive Population
Time frame: Week 4 up to Day 182 (end of study [EoS])
Percentage of Early MG-ADL Responders During C1; Analyzed in the AChR-Ab Seropositive Population
Time frame: Baseline up to Day 63 (end of TC1)
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Feb 2022.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 42234197Howard JF Jr, Sacca F, Hoffmann S, Attarian S, De Bleecker JL, Beauchamp J, Brauer E, Kerstens R, Vissing J, Meisel A; ADAPT Study Group. Clinical effectiveness of efgartigimod in a broad population of patients with generalized myasthenia gravis: subgroup analyses from a randomized, double-blind, placebo-controlled, phase 3 trial (ADAPT). J Neurol. 2026 Jun 3;273(6):363. doi: 10.1007/s00415-026-13877-z.
- Derived from this study: PubMed 41517964Hoffmann S, Zhao S, Callewaert F, Schoppe S, Rozsa C, Spillane J. Post Hoc, Sex-Specific Subgroup Analysis of Efgartigimod in Patients With Generalized Myasthenia Gravis From the ADAPT Trial: A Sex and Gender Equity in Research (SAGER) Guidelines Approach. Muscle Nerve. 2026 Apr;73(4):566-574. doi: 10.1002/mus.70135. Epub 2026 Jan 10.
- Derived from this study: PubMed 39068745Janssen MF, Dewilde S, Wolfe GI, Muppidi S, Phillips G. Psychometric properties of MG-ADL items and MG-ADL score: An assessment of distributional characteristics, validity and factor structure in two large datasets. J Neurol Sci. 2024 Aug 15;463:123135. doi: 10.1016/j.jns.2024.123135. Epub 2024 Jul 22.
- Derived from this study: PubMed 34146511Howard JF Jr, Bril V, Vu T, Karam C, Peric S, Margania T, Murai H, Bilinska M, Shakarishvili R, Smilowski M, Guglietta A, Ulrichts P, Vangeneugden T, Utsugisawa K, Verschuuren J, Mantegazza R; ADAPT Investigator Study Group. Safety, efficacy, and tolerability of efgartigimod in patients with generalised myasthenia gravis (ADAPT): a multicentre, randomised, placebo-controlled, phase 3 trial. Lancet Neurol. 2021 Jul;20(7):526-536. doi: 10.1016/S1474-4422(21)00159-9.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Antonio Guglietta, MD study director
argenx
66 sites in 16 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing ARGX-113 in people with Generalized Myasthenia Gravis, run by argenx at 66 sites in 16 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 8 Feb 2022. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 66 sites in United States, Japan, Poland, Russia, Canada and 11 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 8 Feb 2022). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percentage of MG-ADL Responders During Cycle 1 (C1); Analyzed in the AChR-Ab Seropositive Population (time frame: Baseline up to Day 63 (end of TC1)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03669588, which also lists 4 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Feb 2022.