Arrowhead Pharmaceuticals secured FDA approval for its RNA‑interference therapy plozasiran (Redemplo) for familial chylomicronemia syndrome, making Arrowhead a commercial‑stage RNAi company after two decades of development. The company priced Redemplo well below the incumbent Ionis therapy, framing the launch as a direct commercial challenge that could reshape market access dynamics for rare lipid disorders. Regulatory clearance positions Arrowhead to commercialize a novel RNAi modality while immediately testing pricing and reimbursement strategies against Ionis’ established treatments. Payers and competing manufacturers will monitor uptake, real‑world safety, and the commercial response—particularly whether aggressive pricing drives rapid share shifts or invites patent and litigation responses. The approval also underscores the maturation of RNAi as a therapeutic class and the commercial pressures that follow a small number of category approvals.