FDA Warns About Asthma Drug, Xolair
Extreme Allergic Reactions Seen in Some Patients Using Injected Drug
Feb. 21, 2007 -- The FDA is calling for a "black box" label warning
for the asthma drug Xolair, alerting users it can cause potentially
life-threatening allergic reactions.
The FDA issued the alert after reviewing 48 cases of anaphylaxis --
life-threatening allergic reactions -- submitted to the agency from June 2003,
when Xolair was approved, through December 2005.
These cases included symptoms of bronchospasm (narrowing of airways),
difficulty breathing, drop in blood pressure, fainting, hives, and swelling of
the throat or tongue.
Nearly 15% of the patients required hospitalization. No deaths were
The drug, which is injected, is also known by the generic name
It is approved for use in asthma patients aged 12 and older who have
moderate to severe persistent asthma, and who have tested positive for a
perennial aerial allergen -- such as pollen, grass, or dust.
The drug is a secondary treatment, recommended for those whose symptoms have
not been adequately controlled with inhaled steroids.
Delayed Reaction Possible
The FDA alert warns that patients can have a delayed reaction from two to 24
hours -- or longer -- after injection.
It adds that patients who have not reacted in the past can still develop
anaphylaxis following a later dose.
In about 39,500 patients who took Xolair, the FDA says anaphylaxis occurred
in at least 0.1% of those treated.
The drug is currently injected in a medical setting once every two or four
weeks, depending on the patient, according to an email response from the
Now, the FDA is asking health care professionals who administer Xolair to
observe patients for at least two hours after giving the injection and to be
prepared to manage life-threatening anaphylaxis if it occurs.
Also, patients who take Xolair should be told of the possibility of a
delayed reaction and be able to recognize the signs and symptoms of
anaphylaxis, the FDA says in its alert.
Patients using Xolair should carry medical contact information and an
epinephrine auto-injector (EpiPen). They should also be prepared to begin
treatment on themselves while they seek immediate medical attention should
Xolair was the first biologic, or biotechnology product, developed to treat
such allergy-related asthma when it was brought to the market in 2003.
At the time of the FDA review, Xolair's maker, Genentech, Inc., reported
three cases of anaphylaxis among the 3,507 subjects given the drug in
premarketing clinical trials. Two additional cases were not called
anaphylaxis at that time, but meet the criteria now being used for the
postmarketing cases, the FDA says.
The FDA said in its announcement today that its action is due to the nature
of anaphylaxis reports after the drug reached market, including their
life-threatening potential, their frequency, and the possibility of delayed
In addition to the boxed warning -- the most serious type -- the FDA is
asking Genentech to revise the Xolair label and provide a medication guide for
patients to strengthen the existing warning for anaphylaxis. Genentech is a