FTC: Shire ViroPharma Filed Bogus Petitions to Delay C. Diff Generic

February 7, 2017

Aggressive petitioning by ViroPharma kept a generic equivalent to Vancocin off the market for more than two years.

Shire ViroPharma’s filing of 43 documents and three lawsuits against FDA prevented the agency from approving a generic version of Vancocin, a drug to treat C. Difficile-associated diarrhea, the Federal Trade Association (FTC) alleged on Feb. 7, 2017. This tactic of “sham petitioning,” as the FTC called it, spanned from 2006 to 2012 and successfully prevented the approval of a competitor to Vancocin. The block of Vancocin’s approval cost patients hundreds of millions of dollars, the FTC wrote in its release. FTC alleges that ViroPharma took advantage of the fact that FDA cannot approve any generic applications until it resolves pending citizen petition filings.

The serial petitioning by ViroPharma occurred in 2006 following a FDA recommendation that generic equivalents of Vancocin be tested for bioequivalency in test tube dissolution studies, rather than in human subjects. FTC estimates that it could have approved a generic equivalent of Vancocin as early as July 2010, but that the aggressive tactics from ViroPharma kept the agency from approving a generic to Vancocin until August 2012. Generic versions of the drug from Akorn, Strides Inc., and Watson Laboratories were eventually approved in April 2012.

ViroPharma, as a result, was able to maintain its monopoly on the C. Diff market for an extended period of time. According to the FTC complaint, the filings were the most that any pharmaceutical firm has ever made to FDA concerning a single medication.

Even after 16 experts unanimously decided the filings from ViroPharma had no merit and did not raise any valid scientific issues, the company continued its aggressive tactics, “which ViroPharma understood it needed to have any chance of persuading the FDA of its positions,” according to the complaint. The filings mostly challenged FDA’s bioequivalence guidance.

In addition, ViroPharma didn’t even develop the drug initially. It acquired the drug from Eli Lilly in 2004 and raised the price steadily until 2011. During 2004–2011, Vancocin was ViroPharma’s main source of revenue-sales for the product grew from approximately $40 million in 2003 to almost $300 million by 2011. This all-too-familiar pricing model is especially common with older medications that are no longer protected by patents (such as was the case with Turing Pharmaceuticals and Daraprim).

In related news, Pfizer recently released results from its Phase II trial for a C. Diff. vaccine, which showed the vaccine successfully increased vaccine-elicited neutralizing antibodies to two toxins produced by the bacteria. The vaccine received a Fast Track designation from FDA in 2014.

Source: FTC