How come we suddenly have this new medication, Tamiflu, for swine flu, so quickly?
How come we suddenly have this new medication, Tamiflu, for swine flu, so quickly? Where did this come from?
Chris - Well, the answer is we've actually had Tamiflu, Oseltamivir, and there's another version of that which works in the same way but is made by a rival company and that's called Relenza Zanamivir. These agents were quite carefully designed. They were processed on what's called rational drug design actually. What they do is to target a particle on the surface of a flu virus, which is called the neuraminidase. This is an enzyme that sits down on the surface of the virus. It behaves a bit like a machete and when a virus infects a cell, it tries to bud off or get away from the cell that it's grown in, and in order to do that, it needs to make sure that it doesn't get stuck on to the surface of the cell and also get stuck in any of the mucus, which is on the lining of the airway. And this enzyme cuts the virus adrift and helps it to get free. The way Tamiflu works is by blocking up that enzyme so the virus can't escape from the cell that it's been growing in and this means that it finds it much harder to spread to other cells and this effectively confines the virus to barracks. And so, the infection progresses more slowly, it doesn't infect many other people. It doesn't infect so many other cells in the same person and, therefore, the immune system has a better opportunity to try and curtail the infection a little bit.