Patisiran, sold under the brand name Onpattro, is a medication used for the treatment of polyneuropathy in people with hereditary transthyretin-mediated amyloidosis,[7] a fatal rare disease that is estimated to affect 50,000 people worldwide.

[8] It is a gene silencing drug that interferes with the production of an abnormal form of transthyretin.

[10] Patisiran utilizes a novel approach to target and reduce production of the TTR protein in the liver via the RNAi pathway.

[18] [19][20] The siRNA active component of Patisiran is formulated into lipid nanoparticles, which protect the RNA and facilitate its delivery to target tissues.

[21] As of 2020, there were 1050 people globally receiving patisiran, generating $65.5M in net-revenues for Alnylam Pharmaceuticals.