the study was terminated due to the primary end point being met.

THRIVE is an observational study that will collect information on patients with UCDs. THRIVE will follow enrolled participants for up to 10 years. As an observational study, enrolled patients will not be required to make any additional office visits or take any medicine outside of normal care.

UCDs disproportionately affect children and females: depending on the severity of the defect, a UCD can manifest shortly after birth or later in life. This study will track long-term outcomes in UCD patients and effects of ammonia-scavenging agents on neuropsychological functions of UCD patients.

This is a non-interventional, multi-center registry to be conducted in patients with UCDs. Investigators will prescribe treatments based on usual clinical practice, and there will be no restrictions on the use of commercially available medications. As an observational study, this study will not change the patient/ healthcare provider relationship, nor influence the healthcare provider's drug prescription or the therapeutic management of the patient.

Patients with UCDs will be recruited and invited to attend a Baseline visit. After eligible patients are enrolled, retrospective and baseline data will be collected. Patients will be followed for up to 10 years, during which time they will be assessed by their healthcare provider. Patients and healthcare provider will be asked to report episodes of hyperammonemic crisis, available ammonia values, and other information.

Study acquired from Horizon in 2024.

Inclusion Criteria:

• Confirmed or suspected diagnosis of UCD
• Signed informed consent/Health Insurance Portability and Accountability Act (HIPAA) Authorization and medical records release

Exclusion Criteria:

• Any other reason that, in the Investigator's opinion, makes the patient unsuitable to participate in this study.

Patients with a confirmed or suspected diagnosis of UCD

De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.

Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.

Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest, statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s). In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors. If not approved, a Data Sharing Independent Review Panel will arbitrate and make the final decision. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.

From enrollment through the end of study (mean overall duration on study was 1187.7 days).

Per protocol, non-serious adverse events were not collected in this observational registry study.

Due to data collection complexities in this observational study (e.g., switching of medications, incomplete data on medications, and missing SAE dates) AEs could not be reliably summarized according to a participant's treatment at the time of SAE, and was therefore summarized by treatment at baseline.

Due to data collection complexities in this observational study (e.g., switching of medications, incomplete data on medications, and missing SAE dates) AEs could not be reliably summarized according to a participant's treatment at the time of SAE, and was therefore summarized by treatment at baseline.