AstraZeneca’s Seroquel is already approved by the U.S. Food and Drug Administration (FDA) to be used by people suffering from schizophrenia or the severe mood swings of bipolar disorder.
Now AstraZeneca PLC wants to expand the use of Seroquel and has applied to the FDA for use of Seroquel as a treatment for depression in adults. In response, the FDA has asked AstraZeneca for more information, in the form of a complete response letter (CRL).
Seroquel XR is one of the London-based company’s best-selling drugs next to heartburn drug, Nexium. It reportedly raked in $4 billion in sales last year, according to the Associated Press.
"AstraZeneca is evaluating the contents of the CRL and the proposed labeling revisions," the company said in a statement to the London Stock Exchange."AstraZeneca will continue discussions with the FDA and will provide a response to the agency in due course."
In October, Seroquel received FDA approval for its extended-release version to be used to treat bipolar disorder, making Seroquel XR (“XR” indicates extended release), the first medication cleared for depressive and manic episodes associated with bipolar disorder. It was approved as a once-daily treatment. The previous version was taken twice a day and not approved for mixed episodes.
Recreating the drug with an XR means that the patent is protected until 2017. The original formula was set to expire in 2011. Patients will be switched into the XR version.
Seroquel (Quetiapine Fumarate) was approved by the FDA in 1997.
Earlier this year, Bloomberg reported that teenagers and the elderly were increasingly being given a class of anti-psychotic drugs not cleared by regulators, among them Seroquel and Zyprexa, which had driven growth for both pharmaceutical companies. In adolescents, the medications are given for depression, autism and hyperactivity, and in the elderly for dementia and insomnia.
Half of Seroquel’s sales in 2006 were reportedly for off-label use.
In September 2003, the FDA recommended that six atypical antipsychotics, including Seroquel, carry a diabetes warning because Seroquel patients were three times more likely to develop diabetes than those taking older drugs.
The most common side effects of Seroquel use include, but may not be limited to, drowsiness, weight gain, restlessness, dizziness, increased appetite, constipation and fatigue.
Antipsychotic drugs such as Seroquel have been linked to two serious complications known as Neuroleptic Malignant Syndrome (NMS) and Tardive Dyskinesia.
NMS is a potentially fatal syndrome involving muscle rigidity, an altered mental state and symptoms of cardiac instability (irregular blood pressure, tachycardia, irregular pulse).
Tardive Dyskinesia is a central nervous system disorder characterized by involuntary movements of the limbs as well as twitching of the face and tongue. #