Actavis, which is at the centre of much merger talk, is to acquire Durata Therapeutics and its antibiotic Dalvance in a deal worth at least $675 million.

Actavis has offered $23 per share in cash, plus a contingent value rights element of up to $5 per share depending on how well Dalvance (dalbavancin) does. The intravenous antibiotic was approved by the US Food and Drug Administration in May for acute bacterial skin and skin structure infections and it is also being developed for additional indications, such as hospitalised community-acquired pneumonia and paediatric osteomyelitis.    

Chief executive Brent Saunders said the acquisition of Durata “is a strong strategic fit that strengthens Actavis' emerging infectious disease franchise and aligns with our stated goal to make smart, targeted investments”. He added that Dalvance complements the firm’s antibiotic Teflaro (ceftaroline fosamil) and a ceftazidine-avibactam combination, currently in late-stage development, which are intended for use in the in-patient setting.

Actavis has been reportedly in talks to buy Salix Pharmaceuticals and was rumoured to have had a $50 billion bid turned down by Allergan last month.