BASEL, Switzerland - Swiss drug maker Roche Holding AG said Friday that it is moving to provide smaller child-sized capsules of Tamiflu, the medicine many governments have been stockpiling as an initial defence against a pandemic that might result from the bird flu virus.

Roche said it has already asked the European Medicines Agency, which regulates the use of drugs in Europe, to approve two smaller capsules - 30 mg and 45 mg - and planned a similar filing soon with the Food and Drug Administration in the United States.

"Roche has been granted an accelerated review and is optimistic that EMEA will complete their evaluation by midyear," said a company statement.

The new capsules would be in addition to the 75 mg dosages already approved and will be easier to use than the liquid suspension already available for children, it said. The capsules also will have a longer shelf life than the liquid.

Roche says Tamiflu, or oseltamivir, can reduce the severity of flu symptoms by 38 per cent and can have an even better impact in reducing secondary complications like bronchitis and pneumonia.

Although the lower dosage capsules have been developed mainly for use in children, they also will be useful for the elderly or other adults who have difficulty swallowing the standard capsule, the company said.

Oseltamivir is being stockpiled by governments in case the H5N1 strain of the bird flu virus mutates into a version that is easily transmitted among humans, setting off a pandemic. The medicine would be a first line of defence until a specific vaccine can be developed to target the mutated strain.

Roche says the drug is designed to be effective against various kinds of influenza and that it works by blocking the action of the neuraminidase enzyme on the surface of the virus. "When neuraminidase is inhibited, the virus is not able to spread to and infect other cells in the body," the company statement said.

Flu can be particularly dangerous for the elderly and young children, it said.

"Children younger than two years old are as likely as those over age 65 to be hospitalized because of influenza," Roche said. "It is estimated that children are three times more likely to get sick with the flu on average: one in 10 adults is affected by influenza annually, compared with one in three children."