A Study to Investigate Efficacy and Safety of Pegtibatinase Compared With Placebo in Participants ≥12 to ≤65 Years of Age With Classical Homocystinuria (HCU) Due to Cystathionine Beta Synthase Deficiency Receiving Standard of Care Treatment

ID#: NCT06247085

Age: 12 - 65 years

Gender: All

Healthy Subjects: No

Study Phase: Phase 3

Recruitment Status: Recruiting

Start Date: December 28, 2023

End Date: September 01, 2027

Contact Information:
Travere Call Center
1-877-659-5518
Summary: The purpose of this study is to measure efficacy and safety of pegtibatinase treatment compared with placebo in participants with classical HCU receiving standard of care. Study details include: - Total Study duration: up to 38 weeks - Screening: - Initial Screening duration: up to 4 weeks - Pre-treatment Diet Standardization Period duration: up to 6 weeks - Blinded Treatment Duration: 24 weeks - 2-week blinded dose titration period - 22-week blinded assessment period - Safety Follow-Up: 4 weeks after last dose (as applicable for those not enrolling in the long term extension study, ENSEMBLE)
Eligibility:

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