Bird flu drugmaker halts US supplies

Drugmaker Roche halted supplies of its antiviral drug to the United States to head off hoarding by consumers fearing bird flu, as another firm, and Vietnam, said they were preparing to manufacture their own treatments.

Tests on the latest suspected human cases of the disease produced negative results yesterday, but fear remained high that bird flu was spreading around the world among wild birds and poultry and threatened to produce a human pandemic.

Roche Holding AG said it had halted deliveries of Tamiflu to the US and Canada until the start of the flu season. Media coverage of the spread of the deadly H5N1 strain of bird flu had driven sales higher, the company said.

"This resulted in increased demand for Tamiflu in part from individuals who are doing private stockpiling and at the moment there is no influenza circulating and the threat of a pandemic has not (materialised)," a spokesman said.

"Our priority is to ensure that Tamiflu is available for seasonal use and to fulfil government orders," she added.

British-based GlaxoSmithKline Plc, Europe's biggest drugmaker, said yesterday it was building capacity and converting more factories to make a pandemic flu vaccine, as it develops a prototype shot to counter the H5N1 bird flu virus.

A key challenge in developing a vaccine is how to make the most shots from a minimum amount of active ingredient. Glaxo Chief Executive Jean-Pierre Garnier said his firm had found a way of using an adjuvant, or additive, to greatly expand the amount of vaccine from a given batch of antigen.

"We've been at it for several years now and this gives us good hope for the last bit that remains to be done to come up with a 'shotgun' vaccine on H5N1," he said.

Roche is the only manufacturer of Tamiflu, considered the first line of defence against the H5N1 avian flu virus that some fear could spark an outbreak among humans if it mutates to allow human-to-human transmission. The drug can reduce the severity of influenza and may slow the spread of a pandemic.

Under pressure from generic drug companies, developing nations and the United States, Roche agreed this month to discuss granting licences to others to make versions of Tamiflu.

An EU-backed consortium said it had developed the first human vaccine for a strain of bird flu that may be able to jump from poultry to humans. The H7N1 strain is highly pathogenic but the risk of it emerging as a pandemic strain is lower than H5N1.

Experts say the feared mutation of the virus is most likely to take place in Southeast Asia, where millions of birds have been slaughtered in an attempt to limit its spread.

France said tests on one of three tourists suspected of catching H5N1 in a Thai bird park showed he was not infected. China said a girl in an area hit by an outbreak among birds did not die of bird flu as feared, but of pneumonia.