ARGX-119 for adults with DOK7 congenital myasthenic syndrome

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

Phase 1 Interventional argenx · NCT06436742

This trial tests whether ARGX-119 is safe and well tolerated in adults with DOK7-CMS and also looks at how the body handles the drug and whether it helps symptoms and function.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment16 (estimated)
Ages18 Years and up
SexAll
Sponsorargenx Industry-sponsored
Locations9 sites (Sacramento, California and 8 other locations)
Trial IDNCT06436742 on ClinicalTrials.gov

What this trial studies

Adults with genetically confirmed DOK7-CMS will be randomized 4:1 to receive intravenous ARGX-119 or placebo during a double-blind treatment period, with safety and tolerability as primary focuses. The study will collect pharmacokinetic and immunogenicity data and include measures of symptoms and functional status. After a follow-up period, participants may enter an open-label active-treatment period to receive ARGX-119. The full program from screening through follow-up lasts approximately 38 months.

Who should consider this trial

Good fit: Adults aged 18 or older with genetically confirmed DOK7-related congenital myasthenic syndrome who are medically stable and on a stable dose of any oral beta agonist for at least 3 months, if applicable.

Not a fit: People whose CMS is caused by genes other than DOK7 or who have medical conditions that would confound assessments or increase risk are unlikely to benefit from this study.

Why it matters

Potential benefit: If successful, ARGX-119 could offer a new targeted treatment that improves muscle strength and daily function for people with DOK7-CMS.

How similar studies have performed: Certain symptomatic treatments such as beta-2 agonists have shown benefit for some DOK7 patients, but ARGX-119 represents a novel therapeutic approach that has not yet been proven in this population.

Eligibility criteria

Show full inclusion / exclusion criteria
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.

Where this trial is running

Sacramento, California and 8 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Congenital Myasthenic SyndromeCMS
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.