New hope for anti-bird-flu drug
SCIENTISTS in Hong Kong and the United States have identified a synthetic compound that appears to be able to stop the replication of influenza viruses, including the deadly H5N1 bird flu virus. The search for such new "inhibitors" has grown more urgent in recent years as drugs like oseltamivir have become largely ineffective against certain flu strains, including the H1N1 seasonal flu virus. Experts now question how well and how long the drug would stand up against the H5N1 strain should it unleash a pandemic. Researchers in Hong Kong and the US screened some 230,000 compounds that were catalogued with the US National Cancer Institute and found 20 that could potentially restrict the proliferation of the H5N1 virus. The experts told a news conference yesterday that one of the compounds, called compound 1, showed promise. "We have found a compound that is different from oseltamivir but which acts in the same way," said Leo Poon, a microbiologist at the University of Hong Kong. "An analogy would be like we have a door with a keyhole, but the hole has changed, and the key, in this case oseltamivir, can't lock the door anymore. But we have discovered another keyhole and another key which can lock the door." Their finding was published in the latest issue of the Journal of Medicinal Chemistry. In their experiment, the researchers infected separate batches of cultured human cells with seasonal flu virus and H5N1 and found that compound 1 prevented the replication of both types of viruses effectively. Many advanced countries stock up on oseltamivir and zanamivir, two varieties of the same class of drugs that stops the H5N1 virus from multiplying. But the US Centers for Disease Control and Prevention found that 98 percent of all flu samples from the H1N1 strain were resistant to oseltamivir, which is manufactured by Roche AG and marketed under the brand Tamiflu.
