Being a Human Guinea Pig: What Are the Risks?

March 17, 2006 — -- Shortly after receiving an injection of a new experimental drug on Monday, six men in a research unit in London fell violently ill and developed multiple organ failure.

Now, five days later, four of the men have regained consciousness, the BBC reports, while two are still under sedation in critical condition.

Their harrowing experience -- various reports indicate the men quickly swelled up, having undergone anaphylactic shock, or an extremely potent allergic reaction -- is casting light on the clinical trial process, a system that has undeniably made important and frequent discoveries in medicine, but also creates unavoidable risks for the people who volunteer to be test subjects.

It is not known why the drug the men were given, an antibody therapy known as TGN 1412, caused such serious side effects. The pharmaceutical company testing the product, TeGenero AG, insists that thorough animal studies were done before human testing began.

The trial was known as a phase one study, meaning that the drug was given to healthy people to help determine its safety. Rigorous animal testing is typically done beforehand, and the lowest dose possible is usually administered first. The next step, a phase two trial, includes giving the drug to people with the illness the drug is meant to treat to determine its effectiveness and side effects.

The final step before the drug is allowed to be prescribed is a phase three trial, where large amounts of people are given the drug. And after that, if the drug (or device) is proven effective and passes safety tests, it is usually approved for prescription use.

Unknown problems can arise at any step in this pipeline, researchers say, even when all the scientists involved try their very hardest to prevent any negative outcomes, said Dr. Ezekiel J. Emanuel, chair of the Department of Clinical Bioethics at the National Institutes of Health.

"When the risks are low, that doesn't mean they are zero," Emanuel said. "They might happen."