Shares of the Irvine, Calif.-based Urovant Sciences were soaring 94.01% to $16.07.
Under the agreement, Sumitovant Biopharma will acquire Urovant Sciences for $16.25 a share or about $584 million in an all-cash merger.
The price is a 96% premium over Urovant’s closing share price of $8.28 on Thursday.
Sumitovant is currently Urovant’s largest shareholder, owning about 72% of the company.
All outstanding shares of Urovant stock, other than those held by Sumitovant, will be cancelled and converted into the right to receive $16.25 a share.
The transaction is expected to close in the first quarter of 2021. Urovant will become a wholly owned subsidiary of Sumitovant.
Urovant’s leading product is vibegron, an oral, once-daily treatment for overactive bladder. The company expects the Food and Drug Administration to act on its new drug application for vibegron in the U.S. by Dec. 26.
The company reported positive results from a 12-week Phase 3 study of vibegron.
The privately held Sumitovant has offices in New York and London and is a wholly-owned subsidiary of Japan-based Sumitomo Dainippon Pharma.
"Sumitovant is our largest investor, and we have been partnering closely with them on plans to efficiently launch vibegron and achieve scale as quickly as possible," said James Robinson, president and CEO of Urovant Sciences.
Robinson also said the transaction "benefits Urovant shareholders by derisking our future and providing current and certain value going forward."