Swiss pharmaceutical firm Novartis said on Tuesday that it has agreed to buy privately held, clinical-stage US biotech Anthos Therapeutics for up to $3.1 billion. As part of the agreed terms, Novartis will make an upfront payment of $925 million upon closing of the transaction,

Anthos Therapeutics, based in Cambridge, has a drug in late-stage clinical trials aimed at preventing strokes and blood clots.

(Reuters) -Swiss pharmaceutical giant Novartis has agreed to acquire Anthos Therapeutics, a biopharma firm majority-owned by Blackstone's drug development unit, for up to $3.1 billion, to boost its cardiovascular business.