Peanut Allergy May Be Preventable
New Drug Protects From Reactions; New Finding May Keep Kids From Getting Nut Allergies
March 10, 2003 -- Two new findings push the parameters of peanut allergy protection. One is a new drug. The other may keep kids from getting food allergies in the first place.
The exciting findings come from presentations at this week's annual meeting of the American Academy of Allergy, Asthma, and Immunology. They also appear in the March 13 issue of TheNew England Journal of Medicine.
Why the excitement? Peanut allergy can be deadly. Allergic people get terrible symptoms from foods or other products that contain small amounts of peanuts or peanut oil. Just ask David Flegel, a programming director for WebMD.
"First you feel your lips start to swell, then the back of the throat," Flegel says. "The worst is not knowing how bad it is going to get. There's a feeling of impending doom. Your throat is closing over; you go into shock. You get hives all over. Your heart races. And it's hard to breathe -- it feels like you've got a baseball stuck in your throat. The fear is the worst part. You don't know if this is going to be it, if you are going to be able to keep breathing."
There's no good treatment. A quick injection of the adrenaline-like drug epinephrine can mean the difference between life and death. But it doesn't always work -- and it's a drastic treatment, with serious side effects. The only other thing to do is avoid peanuts or peanut oils. That's hard to do. They are found in foods, drinks, skin lotions, suntan lotion, and hundreds of other products. Flegel eats nothing, puts nothing on his skin, until he's sure it has no trace of peanut. Unfortunately, sometimes peanut or other cross-reacting nut oils aren't on a product's label.
Now help may be on the way. The new drug is called TNX-901. It's a man-made antibody that stops the allergy process in its tracks. It doesn't cure peanut allergy. But in a medium-size trial, allergic people who took the drug didn't get allergic symptoms from eating a small amount of peanut flour. They could eat the equivalent of about six to eight peanuts. Most accidental exposures are equivalent to eating one or two peanuts.
It wasn't easy to get peanut-allergic people to volunteer for the study, note researchers Donald Y.M. Leung, MD, PhD, of National Jewish Medical and Research Center, Denver, and colleagues. But in the end, 84 brave souls volunteered to take various doses of TNX-901 -- or a placebo -- and then eat peanut flour until they got an allergic reaction. Their heroic act may one day save lives.
"These results are highly encouraging," Leung and colleagues write in the NEJM. "[However], TNX-901 is still an experimental drug. Approval for general use will require confirmation of these results in additional studies."
Unfortunately, such studies are not under way. The reason? Three drug companies that had partnered to make the drug are now fighting other over the rights to develop TNX-901 and similar drugs.
That's too bad. Henry Metzger, MD, section chief at the National Institute of Arthritis and Musculoskeletal Diseases, says TNX-901 represents a radical new approach to allergy.
"This tries to take people who are already allergic and prevent them from maintaining that allergic state," Metzger tells WebMD. "So it is not totally prevention, but it is somewhere in between -- it is preventing progression."