Korsana Biosciences completes Cyclerion merger, closes $380 million private placement

Korsana Biosciences, Inc. announced on September 8, 2026 that it had completed its merger with Cyclerion Therapeutics, Inc., with the combined entity operating under the name Korsana Biosciences, Inc. and expected to begin trading on the Nasdaq Capital Market on September 9, 2026, under the ticker symbol "KRSA."¹

Just before the merger closed, Korsana finished a private placement that raised $380 million in gross proceeds from a syndicate of investors headed by Fairmount and Venrock Healthcare Capital Partners, with a group of other investors including General Atlantic, TCGX, Forbion, Wellington Management, RA Capital Management, RTW Investments, Vivo Capital, Janus Henderson Investors, Foresite Capital, J.P. Morgan Life Sciences Private Capital, SR One and Sanofi Ventures also taking part.¹ The financing included common stock and pre-funded warrants for additional shares.¹ Combined with existing cash, the company said this is expected to support operations into 2029, covering multiple clinical milestones for KRSA-028.¹

Under the merger terms, Korsana shareholders received about 0.2074 shares of the combined company's stock for each Korsana share, following a 1-for-7 reverse split of Cyclerion's stock carried out just before closing.¹ After the split, placement, and merger, the company reported roughly 55.1 million shares of common stock and common stock equivalents outstanding, a figure that includes shares tied to pre-funded warrants and Series B convertible preferred stock but excludes shares underlying equity awards.¹

The lead program, KRSA-028, is an investigational shuttled antibody targeting amyloid beta for Alzheimer's disease.¹ The company said Phase 1 healthy volunteer data are expected in mid-2027, with interim proof-of-concept data on amyloid plaque clearance in Alzheimer's patients expected by the end of 2027 or the first quarter of 2028.¹