Shares of Optimer Jump on FDA Drug Approval

The Food and Drug Administration has approved Optimer PharmaceuticalsDificid tablets, a new antibiotic to treat an intestinal infection which affects more than 700,000 U.S. patients each year and can sometimes prove fatal.

Shares of Optimer, which lost more than 7 percent during Friday's Nasdaq session , reversed most of those losses and popped more than 5 percent higher in extended trading. Click here for real-time after-hours quotes.

Dificid is the first new drug approved for the infection in nearly 25 years, according to the company. The FDA approved the tablets based on company trials that showed it worked about as well as an older medication, vancomycin, at treating the infection. The drug proved even more effective at preventing re-infection three weeks after treatment than the older drug.

The new were approved to treat an infection called Clostridium difficile which usually affects older patients. It can cause symptoms ranging from diarrhea to potentially life-threatening inflammation of the colon.