An Efficacy and Safety Study of ARGX-113 in Patients With Myasthenia Gravis Who Have Generalized Muscle Weakness

NCT03669588 | Completed Phase 3 Results DMC FDA Drug

• 2 other identifiers: ARGX-113-17042018-002132-25
• Study Type: interventional
• Target: 167
• Locations: 16 countries
• Sites: 66

Brief 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.

Conditions

Generalized Myasthenia Gravis

Outcome Measures

Primary Outcomes (1)

• 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.

  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

  Baseline up to Day 63 (end of TC1)

• Percentage of MG-ADL Responders During C1; Analyzed in the Overall Population

  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

  Baseline up to Day 126

• Time From Week 4 to Qualify for Retreatment; Analyzed in the AChR-Ab Seropositive Population

  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

  Baseline up to Day 63 (end of TC1)

Study Arms (2)

ARGX-113

EXPERIMENTAL

Biological: ARGX-113

Placebo

PLACEBO COMPARATOR

Biological: Placebo

Interventions

ARGX-113 BIOLOGICAL

Intravenous administration of ARGX-113

Also known as: efgartigimod

ARGX-113

Placebo BIOLOGICAL

Intravenous administration of placebo

Placebo

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.

You may not qualify if:

• 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)
• Hepatitis C Virus (HCV)
• Human Immunodeficiency Virus (HIV)

Sponsors & Collaborators

• argenx: lead

Study Sites (66)

Investigator Site 29

Phoenix, Arizona, 85018, United States

Location

Investigator Site 66

Carlsbad, California, 92011, United States

Location

Investigator Site 5

Los Angeles, California, 90033, United States

Location

Investigator Site 49

Los Angeles, California, 90095, United States

Location

Investigator Site 18

Orange, California, 92868, United States

Location

Investigator Site 40

Palo Alto, California, 94304, United States

Location

Investigator Site 59

San Francisco, California, 94115, United States

Location

Investigator Site 58

Aurora, Colorado, 80045, United States

Location

Investigator Site 34

Jacksonville, Florida, 32209, United States

Location

Investigator Site 4

Tampa, Florida, 33612, United States

Location

Investigator Site 30

Springfield, Illinois, 62702, United States

Location

Investigator Site 25

Iowa City, Iowa, 52242, United States

Location

Investigator Site 21

Kansas City, Kansas, 66160, United States

Location

Investigator Site 27

Boston, Massachusetts, 02115, United States

Location

Investigator Site 48

Detroit, Michigan, 48201, United States

Location

Investigator Site 53

Buffalo, New York, 14202, United States

Location

Investigator Site 3

Chapel Hill, North Carolina, 27599, United States

Location

Investigator Site 20

Cleveland, Ohio, 44195, United States

Location

Investigator Site 9

Portland, Oregon, 97239, United States

Location

Investigator Site 17

Charleston, South Carolina, 29425, United States

Location

Investigator Site

Cordova, Tennessee, 38018, United States

Location

Investigator Site 44

Houston, Texas, 77030, United States

Location

Investigator Site 6

San Antonio, Texas, 78229, United States

Location

Investigator Site 2

Charlottesville, Virginia, 22908, United States

Location

Investigator Site 16

Seattle, Washington, 98195, United States

Location

Investigator Site 11

Edegem, 2650, Belgium

Location

Investigator Site 8

Ghent, 9000, Belgium

Location

Investigator Site 38

Edmonton, Alberta, T6G 2G3, Canada

Location

Investigator Site 24

Toronto, Ontario, M5G 2C4, Canada

Location

Investigator Site 22

Montreal, Quebec, H3A 2B4, Canada

Location

Investigator Site 32

Brno, 62500, Czechia

Location

Investigator Site 35

Ostrava-Poruba, 70852, Czechia

Location

Investigator Site 51

Prague, 128 00, Czechia

Location

Investigator Site 36

Aarhus, 8200, Denmark

Location

Investigator Site 15

Copenhagen, 2100, Denmark

Location

Investigator Site 13

Bordeaux, 33076, France

Location

Investigator Site 52

Marseille, 13385, France

Location

Investigator Site 46

Tbilisi, 0112, Georgia

Location

Investigator Site 45

Tbilisi, 0114, Georgia

Location

Investigator Site 47

Tbilisi, 0114, Georgia

Location

Investigator Site 33

Berlin, 10117, Germany

Location

Investigator Site 55

Budapest, 1204, Hungary

Location

Investigator Site 54

Szeged, 6725, Hungary

Location

Investigator Site 10

Milan, 20133, Italy

Location

Investigator Site 12

Napoli, 80131, Italy

Location

Investigator Site 42

Chiba, Chiba, 260-8677, Japan

Location

Investigator Site 26

Sapporo, Hokkaido, 0608543, Japan

Location

Investigator Site 19

Hanamaki, Iwate, 025-0075, Japan

Location

Investigator Site 43

Sendai, Miyagi, 983-8520, Japan

Location

Investigator Site 28

Ōsaka-sayama, Osaka, 5898511, Japan

Location

Investigator Site 50

Suita, Osaka, 565-0871, Japan

Location

Investigator Site 31

Meguro City, Tokyo, 1538515, Japan

Location

Investigator Site 41

Minato-Ku, Tokyo, 108-8329, Japan

Location

Investigator Site 39

Shinjuku-Ku, Tokyo, 160-0023, Japan

Location

Investigator Site 37

Leiden, 2333 ZA, Netherlands

Location

Investigator Site 7

Gdansk, 80-952, Poland

Location

Investigator Site 57

Katowice, 40-123, Poland

Location

Investigator Site 14

Krakow, 31-505, Poland

Location

Investigator Site 23

Warsaw, 02-097, Poland

Location

Investigator Site 64

Krasnoyarsk, 660037, Russia

Location

Investigator Site 62

Nizhny Novgorod, 603126, Russia

Location

Investigator Site 65

Novosibirsk, 630087, Russia

Location

Investigator Site 60

Samara, 443095, Russia

Location

Investigator Site 61

Belgrade, 11000, Serbia

Location

Investigator Site 63

Edgbaston, B15 2TH, United Kingdom

Location

Investigator Site 56

Liverpool, L9 7LJ, United Kingdom

Location

Related Publications (3)

• Hoffmann 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 Jan 10. doi: 10.1002/mus.70135. Online ahead of print.

  PMID: 41517964 DERIVED

• Janssen 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.

  PMID: 39068745 DERIVED

• Howard 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.

  PMID: 34146511 DERIVED

MeSH Terms

Conditions

Myasthenia Gravis

Interventions

efgartigimod alfa

Condition Hierarchy (Ancestors)

Paraneoplastic Syndromes, Nervous System; Nervous System Neoplasms; Neoplasms by Site; Neoplasms; Paraneoplastic Syndromes; Autoimmune Diseases of the Nervous System; Nervous System Diseases; Neurodegenerative Diseases; Neuromuscular Junction Diseases; Neuromuscular Diseases; Autoimmune Diseases; Immune System Diseases

Results Point of Contact

• Title: Regulatory Manager
• Organization: argenx BVBA

regulatory@argenx.com

+32 93103400

Study Officials

• Antonio Guglietta, MD

  argenx

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR
• Expanded Access: Yes

Study Record Dates

• First Submitted: September 6, 2018
• First Posted: September 13, 2018
• Study Start: August 22, 2018
• Primary Completion: April 6, 2020
• Study Completion: April 6, 2020
• Last Updated: February 8, 2022
• Results First Posted: February 8, 2022

Record last verified: 2021-03

Data Sharing

• IPD Sharing: Will not share

Locations

RU (4); DE (1); GE (3); HU (2); BE (2); FR (2); DK (2); SE (1); GB (2); PL (4); JP (9); NL (1); CZ (3); IT (2); CA (3); US (25)