US drugmaker Gilead Sciences has decided to purchase all of Corus Pharma, which develops respiratory drugs, in a deal valued at $365 million.

The moves comes after Gilead invested $25 million in Corus in April and secured an option to buy the remainder of the company.

Corus' lead product candidate is Cayston (aztreonam lysine for inhalation), an inhaled antibiotic with activity against gram-negative bacteria including Pseudomonas aeruginosa, which can cause lung infections in patients with cystic fibrosis. The company is currently enrolling Phase III studies to evaluate the product as a potential treatment for CF-related pulmonary infections.

This product had been the subject of litigation between Corus and Novartis subsidiary Chiron which almost drove the US minnow into bankruptcy. But Gilead said yesterday this has now been resolved in return for an undisclosed payment.

It had been alleged that Corus used its proprietary technology in the development of Cayston. Chiron markets TOBI (tobramycin for inhalation), a rival inhaled antibiotic for CF-related respiratory infections with sales of $233 million in 2005..

Analysts said the deal went some way towards plugging a near-term gap in Gilead’s pipeline now that it has won approval for Atripla (efavirenz, emtricitabine and tenofovir), a triple therapy for HIV/AIDS, partnered with Bristol-Myers Squibb.