Yet another Acceleron investor challenges Merck's $11.5B acquisition offer: Bloomberg

Merck & Co. can count one more investment firm as an opponent of its planned $11.5 billion takeover of Acceleron Pharma.

Farallon Capital Management, which owns more than a 4% stake in Acceleron, said it doesn’t support the sale of the company at its current $180-per-share price, Bloomberg reported.

“We believe Acceleron has a clear path to substantial value creation as a standalone company, and less strategic assets have recently been sold for far higher valuations,” Farallon said in a statement, as cited by the news service.

In opposing the Merck-Acceleron transaction, Farallon is siding with at least three other institutional Acceleron investors—Avoro Capital, Holocene Advisors and Darwin Global Management—all of whom argue the deal undervalues the biotech.

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The first to publicly defy Acceleron’s move—and perhaps the most vocal dissident—is Avoro, which holds about 7% of shares of the biotech. Run by former Immunomedics chairman Behzad Aghazadeh, who oversaw the antibody-drug conjugate specialist’s $21 billion buyout by Gilead Sciences, Avoro has argued that Acceleron should wait for phase 3 readout from pulmonary hypertension candidate sotatercept rather than pursue a sale now. The TGF-beta modulator is the crown jewel of the Merck deal.

Merck hopes sotatercept could further bolster its cardiovascular disease portfolio, which once had cholesterol meds Zetia and Vytorin before the Organon spinoff. The New Jersey pharma is working on its own pulmonary hypertension drugs, including the Bayer-partnered Adempas and a late-stage inhaled sGC stimulator dubbed MK-5475.

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Meanwhile, even as Merck faces Acceleron shareholder pushback, the deal has hit an antitrust delay. The company has withdrawn and refiled its premerger notice with the U.S. Federal Trade Commission to allow the agency more time for its review. As regulatory clearance is required for the deal to close, Merck has also extended its tender offer time for outstanding Acceleron shares to Nov. 18.

Merck has some supporters despite the shareholder activism. Bristol Myers Squibb, Acceleron’s biggest shareholder with an 11.5% stake and the marketing partner of anemia drug Reblozyl, was reportedly ready to tender its shares. As of Oct. 28, Merck has collected 13.7% of Acceleron shares.