In the first post below, I said that we would be in big trouble if we had to rely on a vaccine for all of our protection against a flu pandemic. The problem is, if we're relying on antiviral drugs, we're in even worse shape. (See my post on this from last March.)
Right now, the only drugs likely to do much of anything against an influenza pandemic are the neuraminidase inhibitors like Tamiflu and Relenza. But the problem is, these drugs really have to be taken early in the course of the infection to be most effective. By the time many people realize that they have the flu, it may be too late to do much about it.
One way to get around that problem would be to take the drugs prophylactically, but that has two serious disadvantages. For one thing, this route might well lead to a quicker development of resistant viral strains, which is something that we already know can happen. And for another, it would burn through huge amounts of drug, and we don't happen to have huge amounts of either one.
Why is that? Well, for one thing, neither compound was selling very well until recently. The companies involved have never had to ramp up production to the levels that people are talking about now. It's doable, but it won't be fun. The ten-step Roche synthetic route to Tamiflu uses some azide chemistry, which is potentially toxic and explosive, but it's nothing that a good bunch of industrial chemists can't handle. (It helps, for example, that India's Cipla already has experience making AZT, because that relies on similar chemistry). But any ten-step route is not going to be trivial to implement if you've never done it before, azide or no azide.
A bigger problem is that these drugs have syntheses from a starting material called shikimic acid. That's a component of an important metabolic pathway in plants. (It's important enough that the well-known herbicide Roundup works by shutting it down). Shikimic acid is found in small quantities in a lot of plant species, but star anise, a spice used in Chinese cooking, has a lot of it. (If you'd like to extract some from any star anise you have in your kitchen, here's how). Roche already has a network of suppliers in China, and the generic companies who plan to produce the drug are having a hard time sourcing the shikimate. It can also be produced by fermentation, which Roche uses for some of its supply, but that's an even more specialized process.
All in all, I think it's prudent to stockpile these drugs, although I'm not sure, for the reasons given above, where the US government is going to find the quantities it's looking for. But even if we can pile the stuff up to the rafters, we have to be ready for the possibility that these drugs may or may not do us much good. I see that I've ended both of these posts on the same note. . .