Drug developer Novavax Inc. said Thursday a clinical trial showed that its seasonal flu vaccine is safe for adults age 60 and older.
The mid-stage study compared two doses of the vaccine with a standard flu shot. A total of 480 subjects participated, Novavax said.
There was no significant increase in side effects for either dose of its vaccine, the company said. In February Novavax said a separate study showed the vaccine was safe for adults age 18 to 49.
The trial was not designed to measure the effectiveness of the vaccine, but Novavax said the larger dose of its shot was significantly more effective against one of the three 2009-10 seasonal flu strains, and there was no difference in response for the other two strains. The lower dose was as effective as the commercial vaccine against two strains, and significantly less effective against the third.
Novavax's flu shot is made with genetically engineered virus-like particles, which resemble a virus but do not have the genetic material a virus needs to reproduce itself. The company says its vaccine can be grown in weeks while traditional vaccine manufacturing methods take months.
In premarket trading, Novavax stock rose 12 cents, or 4.1 percent, to $3.05.