89bio Stock Soars 86%. Why Roche Is Buying the Biopharma Company for $3.5 Billion.
Sep 18, 2025 10:12:00 -0400 by Mackenzie Tatananni | #Biotech and Pharma
Roche said it would acquiring small-cap biopharma company 89bio for $3.5 billion. (Photograph by Ed Jones/AFP/Getty Images)
Key Points
About This Summary
- Roche is acquiring 89bio for $3.5 billion, offering shareholders up to $20.50 a share in cash.
- 89bio’s main asset is pegozafermin, a drug candidate currently in clinical trials for obesity-related conditions.
- Upon closing, 89bio will join Roche’s pharmaceuticals division, with Roche aiming to improve patient care.
Shares of 89bio surged Thursday after Roche announced it was buying the small-cap biopharmaceutical company for $3.5 billion.
As part of the deal, 89bio shareholders will receive up to $20.50 a share in cash, which includes $14.50 a share at closing and a non-tradeable contingent value right of up to $6 a share.
89bio is a late-stage biopharma company valued at $1.2 billion. Its primary asset is pegozafermin, a drug candidate that mimics the chemical structure of a hormone secreted by the liver.
Pegozafermin has yet to secure approval from the U.S. Food and Drug Administration, and is undergoing clinical trials exploring its efficacy at treating conditions commonly linked to obesity, such as a type of fatty liver disease and hypertriglyceridemia.
Upon closing of the deal, 89bio will become part of Roche’s pharmaceuticals division, the drugmaker said.
“We are excited about this agreement and to further develop this promising therapy,” Boris Zaïtra, the head of Roche Corporate Business Development, said in a statement. By adding pegozafermin to Roche’s portfolio, “we are aiming to transform the standard of care and positively impact patients’ lives,” he added.
Shares of 89bio soared 86% to $14.99 on Thursday, putting the stock on pace for its largest one-day percentage increase on record, according to Dow Jones Market Data. U.S.-listed shares of Roche were down slightly, while the benchmark S&P 500 index was up 0.6%.
Write to Mackenzie Tatananni at mackenzie.tatananni@barrons.com