The alert was given after the FDA learned of 48 instances of anaphylactic shock that occurred between June, 2003 and December, 2005. Xolair was approved by the FDA for use in 2003.
Although no deaths have been reported, anaphylaxis is a life-threatening allergic reaction. Reported cases of reaction to Xolair include narrowing of the airways, a drop in blood pressure, fainting, hives, difficulty breathing, and swelling of the throat or tongue. Some of the patients' reactions were serious enough to require hospitalization.
The FDA is warning people that it is possible to experience a delayed reaction to Xolair. The delay can last anywhere from two to more than 24 hours after injection. Anaphylaxis can also develop over time, meaning that someone who has not had a reaction in the past may experience one after a later dose.
Xolair, also known generically as omalizumab, is an asthma drug that is injected into patients while they are in a medical setting. The FDA is warning people who are responsible for administering Xolair to keep patients under observation for at least two hours after giving the injection. Furthermore, patients who use Xolair are urged to carry medical contact information and an EpiPen (epinephrine auto-injector). Patients are also advised to know how to begin emergency self-treatment in case they develop anaphylaxis.
Xolair is manufactured by Genentech, Inc., to treat patients with allergy-related asthma whose symptoms are not adequately controlled through the use of inhaled steroids. It is used for people aged 12 and up who have moderate to severe persistent asthma. At least three cases of anaphylaxis were reported in premarketing clinical trials.
Black box warnings are the most serious type issued by the FDA. The organization said that the addition of the black box warning is due to the life-threatening potential of anaphylaxis. Genentech has also been requested to "revise the Xolair label and to provide a Medication Guide for patients to strengthen the existing warning for anaphylaxis."