New Drug To Fight Allergies

The Food and Drug Administration has paved the way for a brand new drug that combats allergic reactions in a whole new way, which is great news for allergy sufferers.

The Early Show medical correspondent Dr. Emily Senay says Xolair is being heralded as the first major innovation in allergy therapy in 30 years because it targets the body's allergic response before it starts.

It's likely to be approved by the summer for moderate to severe allergic asthma, which can be triggered by a range of different causes, such as infection, cold air, exercise or seasonal allergies (pollen and mold).

In clinical tests, the drug was injected under the skin and it brought relief to people for two to four weeks. A small increased risk of cancer was noted in the trials, but no definitive link was proven.

Dr. Senay explains an allergy is an overreaction by the body's immune system to an otherwise benign substance, such as tree pollen or mold. The immune system reacts to a foreign substance by producing antibodies, which latch onto it and trigger chemicals to help fight the substance.

The new drug blocks an immune system protein called immunoglobulin E (IGE), which prevents the immune system from triggering the release of chemicals like histamine. Dr. Senay says that can cause the body to overreact and result in the allergic symptoms, such as sneezing, sniffling and watery eyes.

The drug is also being tested for peanut allergies, which can be very serious and, in some cases, life-threatening. Researchers found that an anti-IGE antibody made it possible for people to tolerate much higher quantities of peanuts before an allergic reaction was triggered. Peanut reactions result in deaths every year — sometimes after a person accidentally eats even tiny amounts.

The anti-IGE antibody would be the first preventive medicine for peanut allergies, and many doctors hope it will prove to be useful for a wide range of other allergic reactions, such as shellfish or drug allergies.

Dr. Senay says there are existing treatments that target allergies by blocking chemicals that cause the symptoms. Histamine is a chemical that can be blocked by drugs like Claritin and Zyrtec. The asthma drug Singulair was just approved for allergies this year, she says. It blocks chemicals called leukotrienes.

Many patients also seek relief from allergic symptoms with monthly injections to desensitize their immune systems to the things they are allergic to.

The bad news, says Dr. Senay, is Xolair will not be available as a first-line treatment for people with minor allergies. But it will most likely be covered by more severe allergic asthma cases. And most, she says, will need the coverage. The drug will initially have an average cost of $10,000 a year. But the hope is that, over time, the price will go down.