Aug 24, 2005 (CIDRAP News) The Swiss drug company Roche has pledged to give the World Health Organization (WHO) enough doses of the antiviral drug oseltamivir (Tamiflu) to treat 3 million people, in the hope that it could help to stave off or delay an influenza pandemic.
The 30 million doses will be used to build up an international stockpile of antivirals, the WHO said in announcing the gift today. The first 1 million treatment courses (10 million capsules) will be ready early in 2006, with the rest expected before mid-2006. Earlier this month, the WHO said it had enough oseltamivir to treat 120,000 people.
The drug "would be dispatched to people in greatest need at the site of an emerging influenza pandemic," the agency said today. The announcement comes amid growing concern that the H5N1 avian flu virus in Asia may evolve into a humanly contagious form at any time, triggering a pandemic.
"Oseltamivir could help to reduce illness and death, and when combined with other measures, could potentially contain an emerging pandemic virus or slow its national and international spread," the WHO said. "If it reaches the site of an outbreak quickly, an antiviral stockpile could especially help people in poorer countries."
"Right now, many countries are creating their own stockpiles of antivirals," said WHO Director-General Dr. Lee Jong-Wook, as quoted in the WHO announcement. "However poor countries simply cannot afford to do this. If a flu pandemic were to emerge in a poor country for example, these drugs could be flown quickly to the center of a potential pandemic. We urge other countries to help us build up the international stockpile."
Disease experts have warned that stopping a budding pandemic would be extremely difficult at best. The WHO noted that such a thing has never been tried before and said success would depend on meeting tough conditions.
"If the first signs of improved transmissibility are picked up quickly, there is a chance that rapid intervention, involving mass prophylactic administration of antiviral drugs, might contain the pandemic at its source or at least delay international spread, gaining time to intensify preparedness," the agency said.
Officials said the following specific conditions would be required:
- The first viruses that show an ability to sustain transmission among humans would not yet be highly contagious.
- The emergence of such viruses would have to be limited to a small geographical area.
- The first clusters of human cases caused by the virus would have to be rapidly detected and reported.
- Antiviral drugs would be rapidly mobilized from the stockpile and administered to a large enough share of the affected population.
- Movement of people in and out of the area would be effectively restricted.
"While mass intervention with antiviral drugs has no guarantee of success, it nonetheless needs to be undertaken as it represents one of the few preventive options for an event with predictably severe consequences for every country in the world," the WHO said. "Once the virus has become fully contagious, its spread to all parts of the world is considered unstoppable."
Oseltamivir is one of the two flu drugs called neuraminidase inhibitors, the other being zanamivir (Relenza). Of the two, only oseltamivir is approved for prevention (as well as treatment) of flu and for use in children younger than 7 years (and older than 1 year). Both drugs reduce flu severity if treatment is begun within 48 hours after symptoms appear, according to the Centers for Disease Control and Prevention (CDC).
A Roche news release said oseltamivir is likely to be effective against any mutating strain of the H5N1 virus.
The company said it has received orders for oseltamivir from about 30 countries in the past few months, as governments have begun building their own stockpiles. Countries aiming to buy enough of the drug to cover 20% to 40% of their people include France, Finland, Iceland, Ireland, Luxembourg, Netherlands, New Zealand, Norway, Switzerland, and the United Kingdom. Recent news reports said the US government has stockpiled enough oseltamivir to treat about 2.3 million people.
Roche CEO William M. Burns said the production lead time for the drug is about 12 months. The company doubled its production capacity last year and this year, and it plans to increase it further in 2006, he said.
Roche news release
CDC information on neuraminidase inhibitors