Arrowhead Pharmaceuticals, Inc. (“Arrowhead” or the “Company”) (NASDAQ: ARWR) develops medicines that treat intractable diseases by silencing the genes that cause them. Using a broad portfolio of RNA chemistries and efficient modes of delivery, Arrowhead therapies trigger the RNA interference, or RNAi, mechanism to induce rapid, deep, and durable knockdown of target genes. RNAi is a mechanism present in living cells that inhibits the expression of a specific gene, thereby affecting the production of a specific protein. The Company’s RNAi-based therapeutics leverage this natural pathway of gene silencing.