ViroPharma Incorporated announced that the Pharmaceutical Science and Clinical Pharmacology Advisory Committee supports the FDA's Office of Generic Drugs (OGD) draft guidelines on bioequivalence (BE) for Vancocin (vancomycin hydrochloride) capsules. Vancocin is used to treat severe, often life-threatening bacterial infections of the gastrointestinal (GI) tract, Clostridium difficile infection (CDI) and enterocolitis caused by Staphylococcus aureus. The draft guidelines, if approved, would allow generic manufacturers to use less rigorous standards, including in vitro rather than in vivo testing, for establishing BE rather than using comparative clinical trials. ViroPharma scientists and other leading experts voiced their concern that these new guidelines could jeopardize patient safety.

"We're appreciative that the FDA convened this advisory committee to provide a forum for open debate and discussion regarding a serious public health issue," said Vincent J Milano, ViroPharma's president and chief executive officer. "While we're disappointed with the vote, we hope that the OGD will take every precaution to ensure that CDI patients will be treated with truly bioequivalent versions of vancomycin, given the life-threatening nature of the disease."

The Advisory Committee was asked if the proposed OGD guidelines and the use of in vitro dissolution methods are sufficient for establishing bioequivalence for generic vancomycin oral capsules. The Advisory Committee voted unanimously in favour of the proposed OGD recommendation to demonstrate bioequivalence through equivalent dissolution in media of pH 1.2, 4.5 and 6.8 for potential vancomycin HCl capsule generic products that contain the same active and inactive ingredients in the same amounts as Vancocin HCl capsules; meet currently accepted standards for assay, potency, purity, and stability (equivalent to those in place for Vancocin HCl capsules); and are manufactured according to cGMP.

According to ViroPharma, the proposed in vitro test conditions do not mimic the in vivo environment of the CDI patient and the qualitative and quantitative sameness (Q1Q2) is inadequate given formulation and critical manufacturing process controls and lacks correlation with clinical effects. The company also underscored that the adoption of bioequivalence guidelines is precedent setting and patient safety must be a primary concern.

Vancocin is the only approved product to treat Clostridium difficile-associated pseudomembranous colitis, one of the most common and devastating hospital-acquired infections.

ViroPharma Incorporated is a biopharmaceutical company dedicated to the development and commercialization of products that address serious diseases treated by physician specialists and in hospital settings.