Alnylam Completes Rolling Submission of New Drug Application to U.S. Food and Drug Administration (FDA) for Givosiran for the Treatment of Acute Hepatic Porphyria - Seite 2

About ENVISION Phase 3 Study

The ENVISION Phase 3 trial was a randomized, double-blind, placebo-controlled, global, multicenter study to evaluate the efficacy and safety of givosiran in patients with a documented diagnosis of acute hepatic porphyria (AHP). The primary endpoint was reduction relative to placebo in the annualized rate of composite porphyria attacks, defined as those requiring hospitalization, urgent healthcare visit, or hemin administration at home, in patients with acute intermittent porphyria (AIP, the most common subtype of AHP) over six months. Key secondary and exploratory endpoints evaluated reductions in neurotoxic heme intermediates, aminolevulinic acid (ALA) and porphobilinogen (PBG), usage of hemin, symptoms of AHP, such as pain, nausea, and fatigue, as well as impact on quality of life. The trial enrolled 94 patients with AHP, at 36 study sites in 18 countries around the world and is the largest ever interventional study conducted in AHP. Patients were randomized 1:1 to givosiran or placebo, with givosiran administered subcutaneously at 2.5 mg/kg monthly. Upon completion of dosing in the double-blind period, all eligible patients (99 percent) enrolled in the ENVISION open-label extension (OLE) to receive givosiran on an ongoing basis.

About Acute Hepatic Porphyria

Acute hepatic porphyria (AHP) refers to a family of rare, genetic diseases characterized by potentially life-threatening attacks and for some patients chronic debilitating symptoms that negatively impact daily functioning and quality of life. AHP is comprised of four subtypes, each resulting from a genetic defect leading to deficiency in one of the enzymes of the heme biosynthesis pathway in the liver: acute intermittent porphyria (AIP), hereditary coproporphyria (HCP), variegate porphyria (VP), and ALAD-deficiency porphyria (ADP). These defects cause the accumulation of neurotoxic heme intermediates aminolevulinic acid (ALA) and porphobilinogen (PBG), with ALA believed to be the primary neurotoxic intermediate responsible for causing both attacks and ongoing symptoms between attacks. Common symptoms of AHP include severe, diffuse abdominal pain, weakness, nausea, and fatigue. The nonspecific nature of AHP signs and symptoms can often lead to misdiagnoses of other more common conditions such as irritable bowel syndrome, appendicitis, fibromyalgia, and endometriosis, and consequently, patients afflicted by AHP often remain without a proper diagnosis for up to 15 years. In addition, long-term complications of AHP and its treatment can include chronic neuropathic pain, hypertension, chronic kidney disease and liver disease, including iron overload, fibrosis, cirrhosis and hepatocellular carcinoma. Currently, there are no treatments approved to prevent debilitating attacks or to treat the chronic manifestations of the disease.