Ionis Pharmaceuticals, Inc. is engaged in discovering and developing ribonucleic acid (RNA)-targeted therapeutics. The Company, using its drug discovery platform, has developed a pipeline of drugs for patients with unmet medical needs. The Company's segments include Ionis Core and Akcea Therapeutics. In the Ionis Core segment, the Company is engaged in exploiting a drug discovery platform to generate a pipeline of drugs for the Company and its partners. The Akcea Therapeutics segment includes the operations of the Company's subsidiary, Akcea Therapeutics, Inc. (Akcea Therapeutics). Akcea Therapeutics is focused on developing and commercializing volanesorsen and other clinical-stage drugs for serious cardiometabolic diseases caused by lipid disorders. The Company is developing volanesorsen to treat two severe and rare, genetically defined diseases, familial chylomicronemia (FCS) and familial partial lipodystrophy (FPL). The Company offers SPINRAZA, a Generation 2.0+ antisense drug.