At Cubist Pharmaceuticals' labs in Lexington, Mass., researchers feel like they are in a race against time. They are trying to develop antibiotics to fight infections that are becoming increasingly untreatable and deadly. And they feel they are playing catch up with these superbugs.
"You're going after a pathogen that evolves and changes its ability to respond to your drug. So, it's not just that you're going after a target, you're going after a moving target," said Dr. Obi Umeh, Cubist's senior director of clinical research.
According to the Centers for Disease Control, 2 million Americans were sickened by drug-resistant bacteria, and about 23,000 died because the infections proved untreatable.
The agency issued a report in September warning that superbugs are becoming a serious threat to public health. Among the strains the agency deemed the most acute threats, was the hospital-acquired infection Clostridium difficile, a bacteria that affects patients' bowels and can result in diarrhea.
"We are rapidly approaching the point where the antibiotics we've relied on for generations will no longer be available to treat infections that can actually be lethal," said Dr. Michael Bell, deputy director of the Division of Healthcare Quality Promotion at the Centers for Disease Control.
(Read more: Supberbugs are a 'costly war we can't win': Doctors)
Over time, antibiotics lose their impact over bacteria because the pathogens evolve and develop resistance to the drugs, Bell said. The problem, he said, has become more acute in recent years because of the easy availability of antibiotics and their overuse.
"Very recently we looked at how good antibiotic prescriptions are in this country, and about half are unnecessary or the wrong antibiotic," he said. "That's a lot of room for improvement."