Cayston is intended to treat chronic lung infections caused by the bacterium Pseudomonas aeruginosa. ( news - people ) said those lung infections are the biggest killer of people with cystic fibrosis.
The drug will be available in some EU countries in early 2010, Gilead said.
The company said Cayston, or aztreonam lysine, is intended to be given three times per day for 28 days to treat the infection. Cayston was approved conditionally because it addresses an unmet medical need, Gilead said, and could receive full approval after a current late-stage clinical trial is complete.
Gilead said the drug has been approved in Canada. The Food and Drug Administration has asked Gilead to run another study before requesting approval.