Pegtibatinase versus placebo for people 12–65 with classical CBS‑deficient homocystinuria on standard care

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a global, randomized, double‑blind, placebo‑controlled Phase 3 trial enrolling about 70 participants with classical CBS‑deficient homocystinuria who have elevated total homocysteine despite standard care. After a screening period that includes a diet standardization phase to stabilize protein intake, participants are randomized 1:1 to pegtibatinase or placebo for a 24‑week blinded treatment period with an initial 2‑week dose titration and a 22‑week assessment window. Study procedures include regular clinic and some home visits for drug administration, dietary monitoring using an HCU‑specific tool (SING), and remote visits as appropriate. Safety follow‑up is performed 4 weeks after the last dose, with an option to enroll in a long‑term extension (ENSEMBLE) if eligible.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Must be ≥12 to ≤65 years of age, at the time of signing the informed consent
* Must have a diagnosis of classical HCU based on clinical, biochemical, and/or molecular genetic testing
* Plasma tHcy ≥80 µM at Screening visit, with allowance for up to 18 participants who may be enrolled with a Screening plasma tHcy ≥50 to \<80 µM
* Participants who can become pregnant must have a negative pregnancy test before starting the study and must use a highly effective form of birth control (less than 1% risk of pregnancy per year) during the study and for at least 4 weeks after the last dose.
* Willing to maintain a generally stable diet for the duration of the study (unless changes are required based on medical/safety reasons)
* Willing to maintain generally stable intake and doses of betaine, pyridoxine, and medical food for the duration of the study (unless changes are required based on medical/safety reasons)

Exclusion Criteria:

* Diagnosis of Marfan syndrome, methylenetetrahydrofolate reductase (MTHFR) deficiency, or disorder of cobalamin metabolism
* Concurrent disease or condition (eg, history or presence of clinically significant cardiovascular, pulmonary, hepatic, renal, hematologic, gastrointestinal, endocrine, immunologic, dermatologic, neurological, oncologic, or psychiatric disease) that would interfere with study participation or safety (excluding complications of HCU).
* History of major thrombotic event (eg, cerebrovascular accident, myocardial infarction, pulmonary embolism) in the previous 6 months.
* Body weight ≥160 kg.
* Use or planned use of any injectable drugs containing PEG (excluding PEG-containing vaccines)
* Any previous exposure to pegtibatinase and/or previous participation in a clinical study that included administration of pegtibatinase or pegtarviliase
* Prior severe immune reaction to a PEG-containing product

Where it's running

• Phoenix Children's Hospital
  Phoenix, Arizona, United States Recruiting
• Yale University School of Medicine
  New Haven, Connecticut, United States Recruiting
• Emory University
  Atlanta, Georgia, United States Recruiting
• Ann & Robert H. Lurie Children's Hospital of Chicago
  Chicago, Illinois, United States Recruiting
• Maine Health - Maine Medical Center
  Portland, Maine, United States Recruiting
• Uncommon Cures
  Chevy Chase, Maryland, United States Recruiting

+2 more sites. See ClinicalTrials.gov for the full list.

Study contacts

• Study coordinator: Travere Call Center
• Email: medinfo@travere.com
• Phone: 1-877-659-5518

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• Assessing Quality of Life in Patients with Classical Homocystinuria

  This study is trying to understand how classical homocystinuria affects the daily lives of patients and their families by talking to them and creating a questionnaire to measure their quality of life.

  Recruiting University Children's Hospital, Zurich · Zurich · NCT06556615

• Pegtibatinase for Classical Homocystinuria

  This study tests pegtibatinase to see if it is safe and tolerable for people with classical homocystinuria, including children aged 5 and up who have high levels of homocysteine.

  Recruiting Phase 1/2 Travere Therapeutics, Inc. · Aurora, Colorado and 11 other locations · NCT03406611

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.