Wyeth Seeks New FDA Approval for Tygacil

The antibiotic is already approved for the treatment of complicated intra-abdominal infections and complicated skin and skin structure infections in adults. Pharmaceutical companies submit supplemental new drug applications to change the label on drugs that are already approved.

Wyeth's application seeks approval for Tygacil to treat patients with community-acquired pneumonia, a common but serious bacterial lung infection affecting about 5.6 million people in the United States each year, according to the company.

In two clinical studies with 846 patients, data showed Tygacil cured 89.7 percent of patients hospitalized with CAP. Levofloxacin -- an existing treatment for CAP -- cured 86.3 percent of studied patients, Wyeth said.

The most common side effects for Tygacil were nausea, vomiting and abdominal pain.

"As antibiotic resistance continues to be a concern for many strains of the most common bacteria causing CAP, there is a growing need for new options," said Dr. Thomas File, chief of infectious disease services for Summa Health System in Akron, Ohio, in a statement.

Shares of Madison, N.J.-based Wyeth fell 21 cents to $47.63 in morning trading.