Skip to main content
OpenTrials
Active, Not Recruiting

NCT Number: NCT06436742

A Phase 1b Study to Investigate Safety and Tolerability of ARGX-119 in Adult Participants With DOK7-Congenital Myasthenic Syndromes (CMS)

The purpose of this study is to assess the safety and tolerability of ARGX-119 in adult participants with DOK7- Congenital Myasthenic Syndromes. The study will also assess how ARGX-119 is processed by the body (pharmacokinetics), how the immune system reacts to it (immunogenicity), and how it may improve the way patients feel and function.

After the screening period, eligible participants will be randomized in a 4:1 ratio to receive intravenous infusions of ARGX-119 or placebo during the double-blinded treatment period. Participants will then enter the follow-up period. After the follow-up period, participants may enrol in the active-treatment period, where they will receive open-label ARGX-119.

The full duration of the study is approximately 38 months.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Notify Me

Key information

Conditions

Congenital Myasthenic Syndrome CMS Congenital, Hereditary, and Neonatal Diseases and Abnormalities Genetic Diseases, Inborn Myasthenic Syndromes, Congenital Nervous System Diseases Neuromuscular Diseases Neuromuscular Junction Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1

Primary location

Ottawa Hospital Research Institute - Civic Campus, Ottawa, Canada

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • At least 18 years of age.
  • Has genetically confirmed congenital myasthenic syndromes due to mutation of downstream of kinase 7 (DOK7-CMS).
  • Participants taking oral beta agonists (eg, albuterol, salbutamol, ephedrine) must have been receiving the medication for more than 3 months and agree to remain on a same stable dosing regimen of the same medication until the end of the study.

Exclusion criteria

  • Diagnosis of CMS due to mutation of any gene other than DOK7.
  • Known medical condition that would interfere with an accurate assessment of CMS, confound the results of the study, or put the patient at undue risk, as assessed by the investigator.
  • History of malignancy, cancer, unless considered cured by adequate treatment with no evidence of recurrence for more than 5 years. Adequately treated participants with the following cancers can be included at any time: 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.
  • Pregnant or lactating state or intention to become pregnant during the study.

Treatment and study plan

ARGX-119

Biological

Intravenous infusion of ARGX-119

Placebo

Other

Intravenous infusion of placebo

Primary outcomes

  1. Assessment of adverse events (AEs)

    Time frame: Up to week 42

  2. Change from active-treatment baseline over time for 6MWT distance

    Time frame: Up to 72 weeks

    The 6-minute walk test (6MWT) measures the distance a participant walks in 6 minutes. Before and after the 6MWT assessment, the participant's blood pressure, heart rate, and SPO2 will be recorded, and the participant's perception of fatigue and dyspnea will be measured.

Secondary outcomes

  1. Maximum observed serum concentration (Cmax) of ARGX-119

    Time frame: Up to 42 weeks + 72 weeks

  2. Incidence of ADA against ARGX-119

    Time frame: Up to 42 weeks + 72 weeks

    ADA : anti-drug antibodies

  3. Change from baseline over time for key components of the QMG scale

    Time frame: Up to 42 weeks + 72 weeks

    The Quantitative Myasthenia Gravis (QMG) scale is a standardized quantitative scoring system that was developed to assess disease severity based on impairment of body function and structures in patients with MG. Minimum value: 0 (no disease severity); Maximum value: 39 (highest disease severity). The change from active-treatment baseline will be used for the 72 week timepoint.

  4. Change from baseline over time for MG-ADL

    Time frame: Up to 42 weeks + 72 weeks

    The Myasthenia Gravis Activities of Daily Living (MG-ADL) is an 8-item scale that assesses MG symptoms and their effects on daily activities. Minimum value: 0 (normal symptoms); Maximum value: 24 (most severe symptoms). The change from active-treatment baseline will be used for the 72 week timepoint.

  5. Change from baseline over time for PROMIS-GH scale

    Time frame: Up to 42 weeks

    The Patient-Reported Outcomes Measurement Information System Global Health (PROMIS-GH) is a 10-item participant completed quality of life questionnaire that measures global physical health and mental health. The participant records their response to each question on a 5-point Likert scale, with lower scores indicating poorer health (Minimum value: 0, Maximum value: 20)

  6. Change from active-treatment baseline over time for 6MWT cadence

    Time frame: Up to 72 weeks

    The 6-minute walk test (6MWT) measures the distance a participant walks in 6 minutes. Before and after the 6MWT assessment, the participant's blood pressure, heart rate, and SPO2 will be recorded, and the participant's perception of fatigue and dyspnea will be measured.

  7. Change from active-treatment baseline over time for PROMIS PF-WMA-SF

    Time frame: Up to 72 weeks

    The PROMIS PF-WMA-SF is an 11-item, participant-completed questionnaire that assesses lower and upper extremity function and associated activities of daily living. The questionnaire asks the participant to rate the items on a 5-point scale of 5 (without any difficulty) to 0 (unable to do).

  8. Change from active-treatment baseline over time for Neuro-QoL fatigue

    Time frame: Up to 72 weeks

  9. Change from active-treatment baseline over time for FVC

    Time frame: Up to 72 weeks

  10. Change from active-treatment baseline over time for PGI-C

    Time frame: Up to 72 weeks

  11. Change from active-treatment baseline over time for PGI-S

    Time frame: Up to 72 weeks

  12. Change from active-treatment baseline over time for CGI-C

    Time frame: Up to 72 weeks

  13. Change from active-treatment baseline over time for CGI-S

    Time frame: Up to 72 weeks

  14. Change from active-treatment baseline over time for EQ-5D-5L

    Time frame: Up to 72 weeks

  15. Incidence of AEs and SAEs

    Time frame: Up to 72 weeks

    AE : Adverse events ; SAE : Serious Adverse events

Sponsors and collaborators

Lead sponsor

argenx

Industry

Registry information

Official study title

A Phase 1b, Double-Blinded, Randomized, Placebo-Controlled Study to Assess the Safety, Tolerability, Pharmacokinetics, Immunogenicity, and Efficacy of ARGX-119 in Adult Participants With DOK7-Congenital Myasthenic Syndromes

Important dates

Study start
2024
Primary completion
2027
Study completion
2028
First posted
May 31, 2024
Registry last updated
Jul 24, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.