# 1293
Oseltamivir, better known as Tamiflu, has been in the news a good deal the past couple of weeks. Despite some worrying reports of side effects among teenagers in Japan, and concerns over the development of resistant strains of influenza, Tamiflu remains our drug of choice when treating bird flu.
The UK's Scientific Advisory Group (SAG) has recommended that nation take some bold steps to avert a pandemic tragedy, and among them is increasing that nation's stockpile of Tamiflu.
They recommended enough for 75% of the nation, an increase from the current 25% stockpile.
Last week, in what may be an interim step, the UK government announced their intent to purchase another 15 million 10-pill courses of Tamiflu.
Half of the recommended increase.
This $300 million dollar purchase will put the UK far ahead of the United States, and most other nations, in the percentage of Tamiflu stockpiled for their population.
The United States, which currently has roughly 50 million doses (enough for 1/6th the population) hopes to increase that to 80 million doses by the end of next year. At best, that would provide a 25% coverage for the nation.
And of course, that's at the 10-pills per person level.
There is mounting evidence that 10-pills simply isn't enough to treat human H5N1 infection. Clinical trials have been announced where they will study the efficacy of higher doses, with `double the dose for double the duration', or 40-pills per patient, being currently viewed as the protocol most likely to bear fruit.
While it may be two years before a controlled study can answer the question definitively, doctors in South East Asia and the Middle East have apparently been routinely exceeding the 10-pill course of treatment for some time. We simply don't recognize that fact when we count our Tamiflu stockpile.
The use of Probenecid has been suggested as a way to extend Tamiflu stockpiles. This gout medicine, which has been around for 50 years, has long been known to reduce the clearance of many drugs from the system, thereby increasing effectiveness and lowering the dosage required to maintain a proper blood level.
This Probenecid-Tamiflu cocktail hasn't been tried on an avian flu patient, to my knowledge, but there are scientists who believe it is worthy of study.
Of course, we could spend hundreds of millions of dollars increasing our stockpiles, and then find the pandemic strain that emerges is resistant to Tamiflu. Already there have been a couple of cases reported in Vietnam and in Egypt indicating just such a mutation.
In fact, it is argued, that once a pandemic erupts and large quantities of Tamiflu are used to try to contain it, a resistant strain is sure to emerge.
Of course it's possible a resistant strain might emerge. It might even be likely. But these meds might buy us enough time for a vaccine to be developed. Right now, antivirals such as Tamiflu and Relenza (along with the older, lesser preferred mantadines) are our only line of defense against influenza.
Until a vaccine can be developed, manufactured, and distributed - a process that could take 6 months to a year - we are pretty much stuck with these meds. They may not be ideal, but they are all we've got.
Tamiflu, Relenza, and the mantadines are not without side effects. Just like any other prescription medication, they carry the potential to do harm as well as good. Recent reports of psychiatric manifestations in teenagers taking Tamiflu in Japan have made headlines and are resulting in a labeling change to the medicine here in the United States.
Out of millions of patients who took Tamiflu in Japan, however, only a couple of hundred cases of aberrant behavior have been documented. Enough to be worrisome and worthy of further investigation.
With all of these negatives, is it worth following the UK's lead and increasing our Tamiflu stockpiles here in the United States? What is prudent, given the current threat posed by the H5N1 virus?
At a cost of nearly 1 billion dollars, doubling the United State's stockpile of Tamiflu would be a tough sell. Some states, like Florida, have failed to even participate in the current Federal Tamiflu purchase program, and it now appears we will fall short of the 25% coverage goal because of that.
Tamiflu is a big gamble. It is expensive, it has a limited shelf life, and its efficacy against the next pandemic strain has yet to be proven.
And yet, for all of its downsides, it is the best option we have today.
In my mind, it would be prudent to increase our stockpiles. That we should follow the example set by the UK.
I believe we need far more pediatric doses of Tamiflu, and we should be stockpiling alternatives such as Relenza, and even the mantadines as well. None are the perfect weapon against a pandemic, but all have lifesaving potential.
A severe pandemic would be the greatest medical battle mankind has every fought. We would be confronting a viral enemy that could ultimately claim millions of lives. We should use every weapon in our arsenal to mitigate the damage.
They say you should never show up at a gun fight with just a knife.
But having a knife beats showing up empty handed, any day.
