The purpose of this study is to describe the natural history and progression of patients diagnosed with PH1, and to characterize the long-term real-world safety and effectiveness of lumasiran.

Inclusion Criteria:

• Documented diagnosis of PH1, per physician's determination

Exclusion Criteria:

• Currently enrolled in a clinical trial for any investigational agent

Patients diagnosed with PH1 will be managed and treated per routine clinical practice.