Onpattro First siRNA Drug Approved to Treat Polyneuropathy
August 10, 2018 – The U.S. FDA has approved Onpattro™ (patisiran), manufactured by Alnylam Pharmaceuticals, Inc., to treat adult patients who have polyneuropathy due to hereditary transthyretin-mediated (hATTR) amyloidosis. Onpattro is the first in a new class of drugs known as small interfering ribonucleic acid (siRNA) treatments. It is considered the first gene silencing medication.
An estimated 50,000 individuals worldwide live with hATTR, a rare and debilitating condition that affects the heart, peripheral nerves, and other organs. Abnormal buildup of amyloid protein in the body’s nerves and tissues interferes with their regular functions, causing pain, numbness, immobility, and various other symptoms depending on the unique progression of the disease in each individual. Onpattro addresses hATTR at its source by effectively turning off RNA that causes the condition. This halts or alters the production of the amyloid proteins responsible for the effects of hATTR.
In a clinical trial, individuals who received Onpattro experienced better outcomes than those who received a placebo. This included better results in muscle strength, physical sensation, reflexes, blood pressure, heart rate, and digestion. Patients on Onpattro were better able to walk and perform daily tasks of living, and had improved nutritional status compared to patients on placebo. According to the manufacturer, the majority of patients who received Onpattro experienced a reversal of impairments caused by hATTR.
Onpattro must be administered via intravenous infusion, with the recommended dosing determined by weight. Patients should be pre-medicated with antihistamines, acetaminophen, and a corticosteroid. The FDA recommends that patients on Onpattro also take a daily vitamin A supplement, as the drug can cause a decrease in vitamin A serum levels.
Alnylam Pharmaceuticals has launched Onpattro at a list price of $450,000 per year.