Quetiapine (kwe-TYE-a-peen), is a medication, marketed by AstraZeneca as Seroquel and by Orion Pharma as Ketipinor, is an atypical antipsychotic used in the management of schizophrenia and bipolar I disorder, and off-label for a variety of other purposes.
Quetiapine is indicated for the treatment of schizophrenia as well as for the treatment of acute manic episodes associated with bipolar I disorder, as either monotherapy or adjunct therapy to lithium or divalproex. Quetiapine received its initial indication from the FDA for treatment of schizophrenia in 1997. In 2004, it received its second indication for the treatment of mania-associated bipolar disorder. It is sometimes used off-label, often as an augmentation agent, to treat such conditions as obsessive-compulsive disorder, post-traumatic stress disorder, restless legs syndrome, autism, alcoholism, Tourette syndrome, and has been used by physicians as a sedative for those with sleep disorders or anxiety disorders.
In 2005, quetiapine and other antipsychotics were shown by the New England Journal of Medicine to be no more effective than perphenazine (Trilafon), a typical antipsychotic, for the treatment of schizophrenia. However, the subsequent CATIE trial, funded by AstraZeneca and other major pharmaceutical manufacturers, contradicted the 2005 study in certain instances.
A 2005 British Medical Journal report showed that quetiapine was ineffective in reducing agitation among Alzheimer's patients, whose consumption of the drug then constituted 29% of sales; in fact, quetiapine was found to make cognitive functioning worse in elderly patients with dementia.
Use of quetiapine to minimize the symptoms of opioid withdrawal has been studied.
Phase III trials are being conducted to prove quetiapine's efficacy in treating generalized anxiety disorder and major depressive disorder as of January 2007. The company expects to file a New Drug Application for treating generalized anxiety disorder in the second half of 2007 and for major depressive disorder in 2008.
AstraZeneca's patent for Seroquel expires in September 2011, which will allow other companies to manufacture and market quetiapine.
Quetiapine is controversially marketed to parents of moody and irritable teenagers in magazines such as PARADE and TV Guide. The National Institutes of Health recommends against the use of quetiapine and almost all other psychotropic medications (including all atypicals, most antidepressants, and all benzodiazepines) by children or those under 18, observing that teenagers taking quetiapine "may be more likely to think about harming or killing themselves or to plan or try to do so".
Sustained-release quetiapine (Seroquel XR)
AstraZeneca has submitted a New Drug Application for a sustained-release version of quetiapine in the United States, Canada, and the European Union in the second half of 2006 for treatment of schizophrenia. AstraZeneca will retain the exclusive right to market sustained release quetiapine until 2017.
On May 18, 2007, AstraZeneca announced that the U.S. Food and Drug Administration has approved Seroquel XR for acute treatment of schizophrenia. During its 2007 Q2 earnings conference, AstraZeneca announced plans to launch Seroquel XR in the U.S. during August 2007. However, Seroquel XR has only become available in U.S. pharmacies after the FDA approved Seroquel XR for use as maintenance treatment for schizophrenia, in addition to acute treatment of the illness, on November 16, 2007. The company has not provided a reason for the delay of Seroquel XR's launch.
Health Canada approved sale of Seroquel XR on September 27, 2007.
Addiction and abuse
Quetiapine is not currently classified as a controlled substance. Reports of quetiapine abuse have emerged in the medical literature, however. While the drug is usually abused through the crushing and snorting of tablets (insufflation), there have also been reports of intravenous abuse and intravenous co-administration with cocaine. A 2004 report recorded a 30% rate of inmate use in the Los Angeles County Jail, where the drug was obtained by inmates faking schizophrenic symptoms and resold under the street name "quell". Also known as "Susie-Q", the drug may be more commonly abused in prisons due to its capacity to be regularly prescribed as a sedative and the unavailability in prison of more commonly abused substances. A letter to the editor which appeared in the January 2007 American Journal of Psychiatry has proposed a “need for additional studies to explore the addiction-potential of quetiapine”. The letter reports that its authors are physicians who work in the Ohio correctional system. They report that “prisoners ... have threatened legal action and even suicide when presented with discontinuation of quetiapine” and that they have “not seen similar drug-seeking behavior with other second-generation antipsychotics of comparable efficacy”.
Along with benzodiazepines, atypical antipsychotics have sometimes been used to "come down" off cocaine or amphetamines. When used in this manner the slang term "downer" is often applied.