Each month, via Medwatch, the U.S. Food and Drug Administration (FDA) issues updates relating to pharmaceutical products. This includes safety warnings, changes to labels, modifications to formulations, and other updates. Recently, Xolair made this list.

Xolair (omalizumab) is an injectable medication for patients aged 12 and older to treat asthma brought on by allergies.

Approved in 2003 by the FDA, Xolair is for individuals whose asthma symptoms are not responding to inhalable asthmatic drugs. However, the FDA’s updates made a reference regarding Xolair and cancer screening for patients to healthcare practitioners.

The FDA label revision is based on a five-year safety study called “Evaluating the Clinical Effectiveness and Long-Term Safety in Patients with Moderate to Severe Asthma (EXCELS),” conducted by the drug’s maker Genentech.

In it, researchers looked at 5,000 asthma patients taking Xolair compared to 2,500 in a control group that did not. Findings suggested that use of Xolair posed a somewhat increased risk for TIAs (transient ischemic attacks, or mini-strokes) and heart attacks. Due to weaknesses in the study, the exact increase cannot be known.

Additionally, the FDA noted some earlier clinical trials that found a slightly higher cancer rate in individuals using omalizumab related to those not taking it.

While the new EXCELS study didn’t discover any difference in the groups’ cancer rates, the study weaknesses make it so the FDA cannot rule out potential cancer risks. As such, the FDA added information about the new cancer risks to Xolair’s label.

What is Xolair?

Omalizumab (sold as Xolair) is an injectable drug for patients aged 12 and older with moderate to severe persistent asthma and a proven issue with airborne allergens.

Xolair is only offered to asthma patients if a blood test shows “elevated levels of IgE [immunoglobulin E] in their blood,” and when the traditional route of inhaled corticosteroids proves insufficient. It has also been approved to treat chronic hives that can’t be controlled by antihistamines.

Used to treat persistent asthma, Xolair has been shown to decrease the number of asthma attacks caused by allergies, but it has also been shown to have Xolair side effects that include a risk for adverse heart and brain events.

According to the FDA, “the heart and brain blood vessel problems included mini-strokes known as transient ischemic attacks or TIAs; heart attacks; sudden, unexpected chest pain; high blood pressure in the arteries of the lungs called pulmonary hypertension; and blood clots in the lungs and veins.”

Xolair Warning Label

Prior to the FDA updates, Xolair’s past “black box” warning only covered the threat of anaphylaxis. An anaphylactic reaction, signified by swelling of the mouth and throat, trouble breathing, dizziness, itching, and hives, is often seen as a severe allergic reaction.