AstraZeneca will pay $520m to US regulators to resolve allegations that the pharmaceutical giant illegally marketed the anti-psychotic drug Seroquel for uses not approved by the Food and Drug Administration (FDA).

The FDA originally approved Seroquel in September 1997 for the treatment of psychotic disorders, and followed up with further approvals for acute manic episodes associated with bipolar disorder and depression.

AstraZeneca, however, is accused of marketing the drug for other unapproved and possibly unsafe indications, including aggression, Alzheimer’s disease, anger management, anxiety, attention deficit hyperactivity disorder, bipolar maintenance, dementia, depression, mood disorder, post-traumatic stress disorder and sleeplessness.

Regulators contend that AstraZeneca promoted the unapproved uses by unduly influencing the content of company-sponsored medical education programmes and by recruiting doctors with incentives to ghost-write supportive studies.

The marketing of the anti-psychotic drug was also directed at doctors who did not typically treat schizophrenia or bipolar disorder, such as elderly and primary care physicians, paediatric and adolescent physicians, and long-term care facilities and prisons.

The civil settlement rectifies false claims for payment submitted to federal insurance programmes, including Medicaid, Medicare and TRICARE programmes, and to the Department of Veterans Affairs, the Federal Employee Health Benefits Program and the Bureau of Prisons.

Under the terms of the settlement, the federal government will receive $301,907,007 from the civil settlement, and the state Medicaid programmes and the District Of Columbia will share up to $218,092,993.

The US Secretary of the Department of Health and Human Services Kathleen Sebelius said that the settlement sends a clear warning to company’s seeking to defraud the healthcare system.

“This will return hundreds of millions of dollars of taxpayer money to the Medicare trust fund where they belong,” Sebelius said.

In addition to the civil settlement agreement, the resolution of the matter includes a corporate integrity agreement (CIA) between AstraZeneca and the Office of Inspector General of the Department of Health and Human Services to annually review the company’s compliance programme and certify its effectiveness.