Only a few months after agreeing to fork over $109 million in civil penalties related to charges that the Company had provided free samples of the knee injection drug, Hylagan, to physicians as kickbacks for prescription business, Sanofi-Aventis has admitted in SEC filings that it is once again under DOJ Investigation.  Although the details are sketchy, Sanofi’s disclosures to the FDA about the variability in patient responses to Plavix — the blood-thinning, anti-clotting drug that had been a blockbuster for Sanofi and its marketing partner, Bristol-Myers Squibb (BMS), prior to losing patent protection in 2012 – is at the heart of the investigation.

In 2010, the FDA required Sanofi to add a boxed warning to Plavix’s label about the potential for reduced effectiveness in a subgroup of patients who metabolize the drug poorly.  The labeling change followed several studies suggesting that a genetic mutation and simultaneous use of certain heartburn drugs could interfere with Plavix’s effectiveness.  The FDA had informed physicians that tests were available to identify genetic traits that could help predict patient responses to Plavix.

Although DOJ notified Sanofi of its investigation last Summer, the Company only acknowledged the investigation in its recently filed annual report.  The relatively late disclosure shouldn’t come as a total surprise, since the Company has been sued by State Attorneys General in Mississippi and West Virginia, both alleging that Sanofi and BMS knew or should have known since at least 2003 that Plavix has reduced effectiveness in certain patients.  According to the lawsuits, Sanofi and BMS failed to disclose what it knew about Plavix’s effectiveness because they wanted to preserve Plavix sales, which topped $9.3 billion in 2011.

It is unclear at this time where this investigation is headed, but it is unlikely to take Sanofi to a place it wants to go.  In December, Sanofi avoided criminal charges despite the Government’s “Statement of Facts” in the Settlement Agreement that the Company had engaged in an extensive and systematic kickback program of trading free samples of Hylagan to physicians in exchange for prescription business and that, in doing so, Sanofi had inflated the Average Sales Price (ASP) of Hylagan and Supartz (a competing drug which shared the same Medicare billing code), resulting in Medicare overpayments.  Depending on the facts of the Plavix investigation, the Government may take an even tougher stance this time around.