Merck to Buy Cidara in $9.2 Billion Deal as Sales Drop Looms (3)

Merck & Co. agreed to acquire Cidara Therapeutics Inc., a biotech company developing a flu treatment, as part of its ongoing efforts to make up for the upcoming patent loss of its blockbuster cancer drug Keytruda.

Merck will pay $221.50 a share in cash for Cidara in a tender offer, more the twice Thursday’s closing price, for a total transaction value of about $9.2 billion, the companies said Friday in a statement.

Cidara’s shares were up 106% at the start of trading Friday in New York, while Merck’s stock was down 0.8%. As of Thursday’s close, Cidara’s shares ...