Your Drug Was Discontinued

By Andrew Weil M.D.

Eli Lilly was the last U.S. manufacturer of animal insulin, which is extracted from the pancreatic tissue of cows and pigs and has been used by diabetics for more than a half-century. Lilly stopped selling the drug in March, and its last batch expired April 1. From now on, it will sell only synthetic human insulin produced by recombinant-DNA technology.

The problem, according to patient-advocacy groups, is that some people cannot tolerate synthetic insulin. They say patients develop resistance to it or suffer adverse reactions that can be severe, even fatal. Such patients are few, but those few are angry, vocal and organized. They say they need animal insulin to maintain their health, and if it is no longer available in the U.S., their only option will be to get it abroad. But most insurance doesn't cover that, so those without resources would be abandoned to their fate. "I've got a few bottles left," says Joi Shaivitz, 47, an environmental re-searcher from Owings Mills, Md., who suffers from Type 1 diabetes. "If I don't get a new supply, I'm going to die."

In Britain, activist patients have joined together to create the Insulin Dependent Diabetes Trust (IDDT), a charity that maintains an informative website, iddtinternational.org IDDT contends that as many as 10% of insulin-dependent diabetics cannot tolerate synthetic insulin. The group offers lots of anecdotal evidence that animal insulin may be a better therapeutic option for some patients and argues that genetically engineered insulin was allowed on the market on the assumption--not evidence--of its superiority. IDDT says no long-term studies have been carried out to compare synthetic and animal insulins and cites a 2002 review by the prestigious Cochrane Collaboration that found that what studies have been done used poor methodology.

Most doctors, however, believe synthetic insulin is the gold standard for treating Type 1 diabetes and consider the debate over animal vs. human insulin a nonissue. Dr. Richard Jackson of the Joslin Diabetes Center questions IDDT's claims and says randomized studies comparing animal and human insulins have shown no additional benefit from using the animal product.

Meanwhile, the pharmaceutical industry has been developing insulin analogues, molecular variations of human insulin that are absorbed more predictably. The new products could be highly profitable, but I'm not convinced that they have significant advantages over animal insulin. I suspect drugmakers are dropping animal insulin because it is not sufficiently profitable. More money can be made from genetically engineered insulin and even more from fancy analogues.

IDDT says patients with insulin-dependent diabetes should have a choice of therapies, and I agree. If the animal hormone disappears from the market, someone ought to make it available or cover expenses for patients forced to get it overseas.

This is a story about insulin. But it raises larger questions about how much oversight the U.S. government has over pharmaceutical companies and what kind of safety net it can provide when any of us fall through the cracks.

Have a question for Dr. Weil about diabetes? Go to time.com/askdrweil