Health: Fighting over Peanuts

Enter a molecule with the ungainly name of immunoglobulin E, or IgE. One of many biological compounds produced by the body's immune system, IgE apparently evolved to help our ancestors fight off parasitic worms. These days, however, parasitic worms aren't so common--especially in urban areas--and IgE has become something of a nuisance. The higher the level of IgE in your body, the more likely you are to develop allergic reactions to otherwise harmless stuff, like peanuts. IgE-triggered allergies also seem to play a role in certain cases of asthma. Over the past decade, researchers have developed specialized compounds, called monoclonal antibodies, to block the action of IgE and dampen the body's allergic reactions.

As you've probably guessed, TNX-901 is an anti-IgE antibody. Here's where the business complications come in. Three companies--Genentech, Tanox and Novartis--have been working in partnership since 1996 to develop anti-IgE therapies. Their lead anti-IgE product, called Xolair, could be approved for the treatment of allergic asthma by the Food and Drug Administration as early as this summer. When Tanox decided to develop TNX-901 on its own, Genentech and Novartis objected, saying that would dilute their development efforts. Last October arbitrators ruled that Tanox cannot be the sole developer of TNX-901, leaving what looks like a promising treatment in legal limbo.

Could Xolair take TNX-901's place? Not without a lot of new testing. "The problem is that they are not identical drugs," says Dr. Hugh Sampson of Mount Sinai. "We don't know how the doses compare." Any doctor who prescribes Xolair off label to deal with your peanut allergy could well be gambling with your life.

So for now, at least, folks with peanut allergy have to do what they have always done: avoid peanuts in any form, keep an EpiPen on hand and try to lead as normal a life as possible.