The U.S. Food and Drug Administration approved Onpattro, Alnylam Pharmaceuticals Inc.'s RNA-based treatment of a peripheral nerve disease caused by a rare genetic disorder.
Onpattro, or patisiran, is the first approved treatment of adult patients with polyneuropathy caused by hereditary transthyretin-mediated amyloidosis, or hATTR amyloidosis, a rare, genetic, progressive disease characterized by the formation of the protein called amyloid in the peripheral nerves, heart or gastrointestinal tract.
Alnylam's Onpattro, which is designed to prevent the production of the protein known as transthyretin, is also the first small interfering ribonucleic acid, or siRNA, type of treatment approved by the FDA. SiRNA operates within the RNA interference pathway, designed to silence the expression of specific genes associated with diseases, the agency said in an Aug. 10 news release.
The U.S. drug regulator granted the approval based on the results of a study in which 148 patients who received infusions of Onpattro demonstrated better results on measures of polyneuropathy including muscle strength, sensation — such as pain, temperature and numbness — reflexes, blood pressure, heart rate as well as digestion, compared to placebo.
The Onpattro patient group also saw improvements versus placebo in terms of walking, nutritional status and the ability to perform daily activities.
"New technologies like RNA inhibitors, that alter the genetic drivers of a disease, have the potential to transform medicine, so we can better confront and even cure debilitating illnesses. We're committed to advancing scientific principles that enable the efficient development and review of safe, effective and groundbreaking treatments that have the potential to change patients' lives," FDA Commissioner Scott Gottlieb said about the approval.
Previously, the drug received FDA's fast track, priority review, breakthrough therapy and orphan drug designations. The European Medicines Agency also recommended the approval of the drug for the same indication.
The average annual list price for the drug will be $450,000 — $9,500 per vial — based on an average of 2.7 vials administered on an average of 17.5 times per year. The average effective net price after discounts will be $345,000, according to Alnylam.
In a separate Aug. 10 press release, Alnylam said it has agreed on the structure and key terms of value-based agreements with health insurers for Onpattro. The company has agreed in principle with Harvard Pilgrim Health Care Inc. and other major health insurers, with many ongoing discussions.
Based on MMIT, a medical policy reporting agency, the engaged payers cover about 76% of commercial medical lives in the U.S.
Alnylam said the agreements are structured to link the drug's performance in real-world use to financial terms.