Map of life expectancy at birth from Global Education Project.

Tuesday, April 05, 2005

Acetylsalicylic acid

The system of drug patents is justified as providing companies with the financial incentive to do the expensive research and testing needed to develop new drugs. Without a period of exclusive license, no company would invest the hundreds of millions of dollars it takes to get a drug from the laboratory to the CVS.

True enough, one must concede, but there are several problems with this system. Investors don't like risk, so companies are always looking for a good bet or even better, a sure thing, before they spend the money on clinical trials. Another very serious problem is that they have absolutely no interest in studying compounds on which they can't own a patent. Solution? Try to copy existing drugs that we already know are valuable, change them slightly to make them patentable, and then try to sell physicians and consumers on the idea that they should spend money on the new, patented variant. Even if this works honestly and well, it leads to only incremental improvements in medicine for the billions of dollars invested, not to any important breakthroughs. And it means that many possible benefits of well known substances that are already in the public domain are never studied.

Aspirin is a variant of a drug known to the ancients, found in willow bark. The naturally occurring compound can severely upset the stomach, but aspirin, first synthesized in the late 1800s, is much less likely to cause that problem. Aspirin relieves pain and inflammation, which everybody experiences at one time or another, and millions of people -- more and more of them as we grow older -- have arthritis and have reason to take a drug that can do that every day. This is a huge market, probably the biggest drug market of all. But Merck and Pfizer obviously couldn't make any money from it unless they could get people to stop taking aspirin and aspirin-like drugs, and instead take something that they could patent.

Enter the Cox-2 inhibitors, Vioxx, Celebrex, and their cousins. These work no better than aspirin, so the companies had to get them approved on the basis that they are safer. Indeed, it seems they are less likely than aspirin-like drugs to cause the (fairly rare) side effect of gastrointestinal bleeding. Still one problem left for the companies: most people who take aspirin never experience any serious side effects. Solution: a massive advertising campaign to convince consumers that the new drugs are better, and a less public campaign to convince doctors that the dangers of aspirin are so terrible that no-one should take it if they have an alternative.

It worked, and the companies had billions of dollars in annual sales. They started investing in additional clinical trials to try to get their drugs approved for more uses, such as preventing colon cancer, which it is expected that aspirin may also be good for. But who wants to test aspirin for anything? It's off patent. They wound up shooting themselves in the foot, because the new trials revealed that Cox-2 inihibitors increase the risk of heart attack and stroke.

Aspirin has been proven to reduce the risk of heart attacks in people with heart disease. It can be taken at very low doses for this purpose, so the risk of side effects is minimal. (Healthy people should not take it to prevent heart disease, however, as it has not been shown to work for that purpose.) Most people who have arthritis can take aspirin safely, and the truth is, and always has been, that it works just as well as the newer drugs. It has also just been shown that aspirin is just as effective as the more expensive coumadin (which, if purchased at your hardware store, is rat poison) in preventing strokes and ischemic damage in people with cerebrovascular disease. Tens of billions of dollars have been wasted on Cox-2 inhibitors and coumadin, when the people could have been taking aspirin instead at trivial cost.

We know enough about aspirin to use it safely. It should not be given to children with viral illnesses because of the risk of a rare, serious side effect. It should not be taken by people with ulcers, liver or kidney disease, or uncontrolled high blood pressure. Some people are allergic to it. If it does upset your stomach, try a coated version (such as Bufferin). But otherwise, there is no reason to spend more.

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