Anaphylaxis may include trouble breathing, chest tightness, dizziness, fainting, itching and hives, and swelling of the mouth and throat. It can also lead to death.
Xolair was approved by the FDA in 2003 to treat moderate-to-severe persistent asthma in adults and adolescents (12 years of age and above) whose allergic condition is inadequately managed by inhaled corticosteroids.
(Asthma therapy falls into three categories: inhaled short- and long-acting beta-agonists, inhaled and oral steroids, oral leukotriene antagonists, and xanthines. In moderate-to-severe asthma, a combination use of these drugs is typical.)
Anaphylaxis was first reported in Xolair's clinical trials. The cases were reported at a frequency of approximately one in a thousand patients (0.1%).
Since its trials, however, continued reports link Xolair with the life-threatening potential, frequency, and the possibility for the delayed onset of anaphylaxis.
The new black box warning includes the possibility of a patient developing anaphylaxis after any dose of Xolair, even if there was no reaction to the first dose. Also, anaphylaxis after administration of Xolair may be delayed up to 24 hours after the dose is given. Health care providers should be prepared to manage life-threatening anaphylaxis following Xolair administration and observe patients for at least two hours after an injection. Patients should also know how to self-treat for anaphylaxis after being given Xolair.
Patients under treatment with Xolair should be fully informed about the signs and symptoms of anaphylaxis, their chance of developing delayed anaphylaxis following Xolair treatment, and know how to deal with self-treatment should anaphylaxis occur.