Abbott Laboratories is under investigation in the USA over the marketing of its seizure disorder drug Depakote.

The company has revealed in a regulatory filing to the US Securities and Exchange Commission that the Justice Department, through the US Attorney for the Western District of Virginia, is seeking to determine whether Abbott's sales and marketing activities for Deapakote (divalproex) violated civil or criminal laws. In particular, the probe is examining any irregularities “in connection with Medicare and/or Medicaid reimbursement to third parties”.

Depakote, approved as a treatment for bipolar disorder and seizures, plus the prevention of migraines, has been a major earner for Abbott. However it now faces generic competition and sales in the third quarter sank 70.9% to $92 million.

In January, the US Food and Drug Administration issued Abbott with a warning letter about “the dissemination of violative promotional materials” used for Depakote. Specifically, the agency said that a promotional flashcard shown to doctors was misleading because it omitted risk information and illegally broadened the indication of the treatment. The flashcard was subsequently withdrawn by Abbott.

News of the probe comes at a time when drugmakers are under the spotlight for their marketing practices. Most recently, in September, Pfizer pleaded guilty to illegal promotion of a number of drugs, notably the withdrawn anti-inflammatory Bextra (valdecoxib) in what was described as “the largest healthcare fraud settlement in the history” of the DoJ.