Xolair Side Effects May Cause Heart Problems, Cancer: FDA Warns

Federal drug regulators indicate that side effects of Xolair may increase the risk of severe heart problems, cerebrovascular events and possibly even cancer, resulting in new warnings for the Genentech asthma injection. 

In a drug safety communication (PDF) issued on September 26, the FDA indicates that data from a long-term study suggests that users of Xolair may be more prone to suffer heart attacks, mini-strokes, chest pain, pulmonary hypertension, deep vein thrombosis, pulmonary embolism and other serious health problems.

The agency also indicated that it is unable to rule out the possibility of a link between Xolair and cancer, resulting in the addition of new warnings about this potential risk as well.

Xolair Heart Problems, Cancer Risk

Xolair (omalizumab) is a subcutaneous injection that was approved in 2003 for use among adults and children ages 12 and older who suffer from moderate to severe asthma that is not well controlled by inhaled corticosteroids. It is also approved for use among patients 12 and older with chronic idiopathic urticaria (CIU), which involves chronic hives without a known cause.

Following a review of data from a 5 year safety study conducted by Genentech, known as EXCELS (“An Epidemiologic Study of Xolair (omalizumab): Evaluating Clinical Effectiveness and Long-Term Safety in Patients with Moderate to Severe Asthma”), the FDA determined that the drug maker must add new warnings to the Adverse Reactions section of the drug label about an increased rate of cardiovascular and cerebrovascular serious events. In addition, information will be added to the Warnings and Precautions section about the potential Xolair cancer risk.

The FDA first raised concerns about the potential risk of Xolair heart problems in 2009, after preliminary data from the same study identified a disproportionate increase in ischemic heart disease, arrhythmias, cardiomyopathy, heart failure, pulmonary hypertension, cerebrovascular disorders and problems associated with blood clots, like pulmonary embolism.

The study was a long-term observational cohort study involving 7,500 patients, with about 5,000 of those receiving Xolair and the remaining 2,500 treated with a placebo.

“Our review of [the] 5-year safety study found a slightly higher rate of heart and brain blood vessel problems occurred in patients being treated with Xolair compared to those patients not treated with Xolair,” the FDA warning states. “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. Although the data are suggestive of a serious safety signal, due to weaknesses in how the safety study was designed and carried out, we are unable to definitively confirm or determine the exact increased level of these risks with Xolair.”

To further evaluate the risk, the agency also reviewed a pooled analysis of 25 randomized double-blind, placebo controlled clinical trials that lasted between 8 and 52 weeks. Although no increased risk of heart and brain problems from Xolair was noted in this combined analysis, the agency indicates that the low number of events, young patient population and short duration of follow up prevent them from making any definitive conclusions about the absence of a risk.

Warnings about the potential risk of cancer from Xolair are also being added to the warning label in response to findings of prior clinical trials, which suggested there may be higher rates of certain types of cancer among Xolair users. Although FDA investigators were unable to find such a link in this new study, they were unable to rule out a potential Xolair cancer risk due to the way the EXCELS study was structured.

Xolair Side Effects

Xolair is only approved for use among patients who have a positive skin or blood test to year-round allergens in the air and whose symptoms are not well controlled by other asthma medications. However, it is was used by an estimated 40,000 patients in the U.S. in 2007.

In 2007, the FDA required Genentech to add a new “black box” warning about Xolair side effects, indicating that users may suffer serious and potentially fatal allergic reactions, known as anaphylaxis. About one in 1,000 patients may experience problems, regardless of the dose or how long they have used the medications.

Symptoms of anphylaxis reactions from Xolair may include trouble breathing, chest tightness, dizziness, fainting, itching, hives, and swelling of the mouth and throat.

Earlier this year, a report by the Institute for Safe Medication Practices (ISMP) raised questions about the large number of hypersensitivity problems among Xolair users reported to the FDA last year, suggesting that the rates are high enough to raise questions about whether Xolair should remain on the market.

Following the addition of these latest warnings about the potential risk of heart attacks, mini-strokes, blood clots and other serious health problems associated with the medication, a number of former users may pursue potential Xolair lawsuits against Genentech, over failure to previously provide stronger warnings about this potential risk.