Generic Vancocin prompts industry speculation of FDA practices

April 20, 2012

FDA?s approval (April 10) of generic versions of ViroPharma?s antibiotic Vancocin (vancomycin hydrochloride) for the treatment of Clostridium difficile-associated diarrhea, has some industry experts wondering if FDA is trying to speed up the availability of generics or politically favor new company competition in select areas of therapy.

FDA’s approval (April 10) of generic versions of ViroPharma’s antibiotic Vancocin (vancomycin hydrochloride) for the treatment of Clostridium difficile-associated diarrhea, has some industry experts wondering if FDA is trying to speed up the availability of generics or politically favor new company competition in select areas of therapy.

The news of the new generics sent ViroPharma’s shares down 20%. In addition, the Exton, Pa.-based company said FDA has denied its citizen petition related to bioequivalence and exclusivity for its Vancocin capsules and would seek an injunction to suspend FDA's approval of the generic versions of Vancocin. Both generics manufacturers Akorn and Watson said they have started shipping the generic version of Vancocin. According to IMS Health, Vancocin generated sales of about $328 million in the United States for 12 months ending December 31, 2011.

According to RTT News, for the past 5 years ViroPharma has had issues with FDA over the agency's proposal to change the evaluation process and approval guidelines used to approve generic drugs.

“The issue is FDA policy of science versus politics, an issue that has been looming larger,” Randy Vogenberg, PhD, told Formulary. Vogenberg is principal at the Institute for Integrated Healthcare in Sharon, Mass., and cofounder, Bentelligence in Connecticut. “Implications are various and can impact many stakeholders to include health plans, PBMs, and purchasers of healthcare [self-funded employers],” he added.

ViroPharma also said that FDA refused its bid to extend the market exclusivity of Vancocin by an additional 3 years. The company had filed a supplemental new drug application for Vancocin. FDA said in order for an old antibiotic such as Vancocin to be eligible for a grant of exclusivity, it must be a significant new use or indication, according to RTT News. ViroPharma believes that FDA has made a mistake in interpreting its bioequivalence regulations in a manner that provides it with broad discretion to permit in vitro bioequivalence testing in the absence of a waiver of in vivo testing.

In addition, ViroPharma received notification that the Federal Trade Commission (FTC) is conducting an investigation into whether ViroPharma has engaged in unfair methods of competition with regard to Vancocin.

In a company press release, ViroPharma said it does not believe that it has engaged in unfair methods of competition with respect to Vancocin. The company intends to cooperate with the FTC investigation.

In similar news, Mylan Pharmaceuticals has filed suit against FDA seeking to overturn a decision by FDA, which awarded Teva sole 180-day exclusivity for the generic version of its affiliate Cephalon's Provigil (modafinil), according to a company press release.

The complaint alleges that Teva did not maintain valid paragraph IV (PIV) certifications as a result of its acquisition of Cephalon. The complaint states that, once Teva became the owner of Cephalon, Teva could no longer infringe its own patents through a PIV certification and that Teva, therefore, is not entitled to exclusivity based on patent certifications. Mylan also alleges that FDA should have found that Mylan is the sole first filer on 1 of the Orange Book Patents for Provigil, that Teva abandoned its abbreviated new drug application (ANDA), and that FDA should have approved Mylan's ANDA for this product. Mylan is seeking an immediate order from the Court entitling it to exclusivity and immediate approval for its ANDA.

The complaint also alleges that FDA’s decision, which blocks Mylan and other generic entrants from launching their generic Provigil products, is unlawful. Mylan believes the FTC did not contemplate the current outcome when it imposed its conditions on the Teva/Cephalon merger. As a result of FDA's decision, only 1 party, Teva/Cephalon, is controlling 100% of the supply of product in the marketplace. This is despite the fact that Cephalon previously agreed to a Mylan launch of its generic product no later than April 6, 2012.

Mylan is seeking immediate equitable relief from the Court requiring FDA to approve Mylan's ANDA.

“One would have to wonder what this means for other branded products and new biosimilar regulations coming out of FDA,” Vogenberg said. “Is the Office of Generic Drugs an example of what FDA in general is now thinking of doing? If so, it raises many red flags around assuring patient safety and efficacy when taking approved medications.”

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