Ionis Pharmaceuticals, Inc. and Ono Pharmaceutical Co., Ltd (Ono), announced that the two companies have entered into a license agreement in which Ono obtains exclusive global rights for the development and commercialization of sapablursen, an investigational RNA-targeted medicine for polycythemia vera (PV), a rare and potentially life-threatening hematologic disease. Sapablursen is currently being evaluated in adults living with PV in the fully enrolled Phase 2 IMPRSSION study. Sapablursen was granted Fast Track designation and orphan drug designation in 2024 by the U.S. Food and Drug Administration (FDA).

Under the terms of the agreement, Ionis will receive a $280 million upfront payment, with the potential to earn up to $660 million in additional payments based on the achievement of development, regulatory and sales milestones. Ionis is also eligible to earn royalties in the mid-teen percentage range on annual net sales of sapablursen. Ionis will be responsible for the completion of the ongoing Phase 2 IMPRSSION study, while Ono will be solely responsible for subsequent development, regulatory filings and commercialization. The transaction is subject to the requirements of the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (HSR Act).

“We are pleased to entrust sapablursen to Ono, whose unique capabilities will help maximize its value by ensuring broad access for people living with PV,” said Brett P. Monia, Ph.D., chief executive officer, Ionis. “Ionis remains committed to advancing the wholly owned medicines we choose to commercialize ourselves, which includes our first independent launch currently underway and three additional anticipated launches in the next three years. Streamlining our Ionis-owned portfolio provides financial flexibility, supporting our commitment to invest in and focus on our near and mid-term commercial opportunities and generate substantial revenue growth.”

“We are delighted to enter into this collaboration with Ionis Pharmaceuticals, a pioneer in RNA-targeted medicines, for sapablursen. This partnership aligns with our strategy to strengthen our pipeline in hematology. We expect sapablursen to become a new treatment option for PV patients worldwide,” said Toichi Takino, president and COO, Ono.