Swiss pharmaceutical giant Roche says it could allow rival firms to manufacture its antiviral drug Tamiflu amid growing fears of a flu pandemic.
The Basel-based firm also announced on Tuesday that it is building a new manufacturing plant in the United States to boost production of the drug.
Roche said the facility would form part of a network of more than a dozen production sites for Tamiflu worldwide.
"For Tamiflu, the key need today is the rapid expansion of production capacity," said William Burns, head of the Basel-based firm's drug division.
"In addition, we are prepared to discuss all available options, including granting sub-licences, with any government or private company who approach us to manufacture Tamiflu or collaborate with us in its manufacturing."
Roche, the sole manufacturer of Tamiflu, has ruled out relinquishing the patent for the drug, which is protected until 2016. But it has pledged to increase production of the drug up to tenfold from 2003 levels to meet demand.
An Indian generic drugs maker, Cipla, has announced it wants permission to produce the drug.
Roche said on Tuesday that it would be willing to discuss giving a production licence to Cipla but had not yet been approached by the company.
Tamiflu, known generically as oseltamivir, is the most effective anti-viral drug currently available for avian flu.
Roche has come under pressure in recent weeks to loosen its grasp on the patent that protects the treatment, with calls from the United Nations to remove the commercial barriers to producing the drug.
David Nabarro, UN coordinator for avian and human influenza, said on Monday that an agreement about the stockpiling and control of antiviral drugs like Tamiflu needed to be reached to guarantee that poor countries would have access to medicines.
"It will be most unfortunate if the stocks that are available are sequestered and they're inaccessible to the people who might need them because their community is poor," he said.
Governments are rushing to build stocks of the treatment, with 40 nations having placed bulk orders with Roche so far, including Turkey which reported cases of bird flu last week.
Roche is reported to be donating 20,000 packs of Tamiflu to Turkey to protect workers who might come into contact with infected poultry. The company has also given three million packs to the World Health Organization.
Jump to humans
A suspected case of bird flu was detected in a bird in Greece on Monday, increasing concerns that the deadly H5N1 virus could be spreading into Europe from Asia, where it has claimed 60 lives since first being detected in 1997.
Most human bird flu cases have been traced to contact with poultry, but experts fear the virus could mutate into a form that could be easily spread among people.
Last week Switzerland banned poultry imports from Turkey and Romania after both countries reported cases of bird flu.
The Federal Veterinary Office said on Tuesday that it would ensure no poultry is imported from Greece, which has to comply with strict European Union regulations in the event of an outbreak.
EU foreign ministers held emergency talks in Luxembourg on Tuesday to discuss the approaching danger of avian flu.
At the weekend Switzerland's medical and pharmacists' associations asked their members to calm public fears of bird flu and to discourage purchases of Tamiflu.
Demand in Switzerland for Roche's antiviral treatment has risen on fears of a bird flu pandemic, fuelled by the arrival of the virus on Europe's shores.
The Swiss government says it has a stockpile to cover 25 per cent of the population in the case of a pandemic.
swissinfo with agencies
Roche is a world leader in diagnostics, the leading supplier of medicines for cancer and transplantation and a market leader in virology.
In 2004 pharmaceutical sales totalled SFr21.7 billion ($16.7 billion), while its diagnostics division posted sales of SFr7.8 billion.
Roche employs around 65,000 people in 150 countries.
The H5N1 strain first emerged in Hong Kong in 1997, when it caused the death or destruction of 1.5 million birds. Eighteen people fell ill, of whom six died.
It re-emerged in 2003 in South Korea and has spread to several countries including China, Vietnam, Thailand, Laos, Indonesia, Turkey and Romania.
H5N1 has infected 117 people in four countries and killed 60, according to the WHO.