ENVISION: A Study to Evaluate the Efficacy and Safety of Givosiran (ALN-AS1) in Patients With Acute Hepatic Porphyrias (AHP)

ENVISION: A Phase 3 Randomized, Double-blind, Placebo-Controlled Multicenter Study With an Open-label Extension to Evaluate the Efficacy and Safety of Givosiran in Patients With Acute Hepatic Porphyrias

The purpose of this study is to evaluate the effect of subcutaneous givosiran (ALN-AS1), compared to placebo, on the rate of porphyria attacks in patients with Acute Hepatic Porphyrias (AHP).

Inclusion Criteria:

• ≥ 12 years of age
• Diagnosed with Acute Hepatic Porphyria (Acute Intermittent Porphyria, Hereditary Corproporhyria, Variegate Porphyria, aminolevulinic acid (ALA) dehydratase deficient porphyria)
• Elevated urinary or plasma porphobilinogen (PBG) or ALA values within the past year,
• Have active disease, with at least 2 documented porphyria attacks within the last 6 months
• Willing to discontinue or not initiate the use of prophylactic hemin throughout the study.
• Women of child bearing potential must have a negative serum pregnancy test, not be nursing, and use acceptable contraception

Exclusion Criteria:

• Clinically significant abnormal laboratory results
• Anticipated liver transplantation
• History of multiple drug allergies or intolerance to subcutaneous injections
• Active HIV, hepatitis C virus, or hepatitis B virus infection(s)
• History of recurrent pancreatitis