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ENVISION: A Study to Evaluate the Efficacy and Safety of Givosiran (ALN-AS1) in Patients With Acute Hepatic Porphyrias (AHP)
NCT03338816 · View on ClinicalTrials.gov ↗
Study Summary
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).
Conditions Studied
Interventions
- DRUG Placebo
- DRUG Givosiran
Study Locations (20)
Other
- Clinical Trial Site — Auchenflower
- Clinical Trial Site — Camperdown
- Clinical Trial Site — Sofia
- Clinical Trial Site — Edmonton
- Clinical Trial Site — Odense
- Clinical Trial Site — Helsinki
- Clinical Trial Site — Paris
- Clinical Trial Site — Chemnitz
- Clinical Trial Site — Munich
Arkansas
- Clinical Trial Site — Little Rock
California
- Clinical Trial Site — San Francisco
Massachusetts
- Clinical Trial Site — Boston
Michigan
- Clinical Trial Site — Ann Arbor
New York
- Clinical Trial Site — New York
North Carolina
- Clinical Trial Site — Winston-Salem
Pennsylvania
- Clinical Trial Site — Philadelphia
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 94 participants |
| Start Date | 2017-11-16 |
| Est. Completion | 2021-05-31 |
| Phase | Phase 3 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT03338816
The ClinicalTrials.gov registry entry for NCT03338816 describes a study currently listed as completed. It is categorized as Phase 3, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 94 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Alnylam Pharmaceuticals, which has 81 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 7 conditions, with Acute Hepatic Porphyria appearing as the primary indexed condition, and to 2 interventions — of which Placebo is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT03338816 reports 20 study locations spanning 12 distinct geographic areas — top geographies include Other, Arkansas, California. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT03338816 about?
NCT03338816 is a clinical study titled "ENVISION: A Study to Evaluate the Efficacy and Safety of Givosiran (ALN-AS1) in Patients With Acute Hepatic Porphyrias (AHP)". 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).
What is the current status of trial NCT03338816?
This trial is currently completed. It is a Phase 3 study. The enrollment target is 94 participants. The study started on 2017-11-16. Estimated completion is 2021-05-31.
What conditions does trial NCT03338816 study?
This clinical trial studies the following conditions: Acute Hepatic Porphyria, Acute Intermittent Porphyria, Porphyria, Acute Intermittent, Acute Porphyria, Hereditary Coproporphyria (HCP). These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT03338816?
The interventions under investigation include: Placebo (DRUG), Givosiran (DRUG). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT03338816?
This trial is sponsored by Alnylam Pharmaceuticals, which has 81 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT03338816 being conducted?
This trial has 20 study locations across Arkansas, California, Massachusetts, Michigan, New York. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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