Recruiting

Sapropterin

Sponsor:

Gregor Andelfinger

Code:

NCT07574034

Conditions

Multisystemic Smooth Muscle Dysfunction Syndrome

Eligibility Criteria

Sex: All

Age: 0 - 18

Healthy Volunteers: Not accepted

Interventions

Kuvan (Sapropterine)

Study Details

Brief summary:

There is currently no approved treatment for multisystem smooth muscle dysfunction syndrome (MSMDS). This single-patient study is the first to be conducted in a child with MSMDS in Canada and was designed to provide the child with access to sapropterin treatment. The molecule that will be used, sapropterin (Kuvan), is already approved and available for other indications. This disease is caused by a genetic variant in the ACTA2 gene. This variant prevents the small units of actin fibers, which are the molecular motors of the smooth muscle cell, from assembling correctly. The goal is to gather data so that the drug can be approved for this indication and thus treat the patient.

Conditions

Multisystemic Smooth Muscle Dysfunction Syndrome

Study ID

NCT07574034

Start date

Jul 15, 2026

Status verified date

Mar, 2026

Completion date

Jun 1, 2030

Anticipated

Primary completion date

Jun 1, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 0 - 18

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Patients with the following molecularly confirmed genotype: ACTA2 c.536G>A, p.Arg179His
  • Aged 1 month to 18 years

Exclusion Criteria:

  • Previous exposure to Kuvan®, Biopten®, or any preparation of tetrahydrobiopterin for greater
  • Known hypersensitivity to Kuvan® or its excipients
  • Known hypersensitivity to other approved or non-approved formulations of tetrahydrobiopterin
  • Current use of medications that are known to affect nitric oxide synthesis, metabolism or action
  • Current use of experimental/other investigational or unregistered drugs that may affect the study outcomes
  • Inability to comply with study procedures
  • Concurrent disease or condition that would interfere with study participation or increase the risk for adverse events, including stroke, renal or hepatic failure
  • Other significant disease that in the Investigator's opinion would exclude the subject from the trial
  • Any condition that, in the view of the Principal Investigator renders the subject at high risk for failure to comply with treatment or to complete the study

Study Design

Enrollment

1 participant

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Open label Intervention

Participant will receive KUVAN® (sapropterin dihydrochloride) 100 mg Powder Packets once daily.

Interventions

Kuvan (Sapropterine)

Sapropterine is already approved in Canada for the treatment of phenylketonuria (PKU) and has shown promise as an agent against multisystem smooth muscle dysfunction syndrome (MSMS) in an animal model. No clinical trials are currently underway with sapropteride for MSMS.

Primary outcome measure

  • Crossing of percentile of growth [ Time Frame: 2 years ]
  • Increase of mean diastolic blood pressure by more than 8 mmHg [ Time Frame: 2 years ]
  • Absence of cerebral vascular complications [ Time Frame: 2 years ]
  • Absence of progression of cerebral vascular disease [ Time Frame: 2 years ]

Central Contacts and Locations

Locations

CHU Sainte-Justine

Recruiting

Montreal, Quebec, Canada, H3T 1C5

Contacts

Nawel Akli

514-345-4931nawel.akli2.hsj@ssss.gouv.qc.ca

More Information

Sponsor

Gregor Andelfinger

Last update posted

Nov 5, 2026

Last verified

Mar, 2026

Keywords

  • multisystemic smooth muscle dysfunction syndrome
  • MSMDS
  • Sapropterine
  • Kuvan

Trial information was received from ClinicalTrials.gov and was last updated on 2026-11-06. This information was provided to ClinicalTrials.gov by Gregor Andelfinger on 2026-11-05. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.