In a recent decision, Ranbaxy v. Leavitt, the federal district court for the District of Columbia held that the FDA improperly denied Ivax’s (a division of Teva) and Ranbaxy’s citizen petitions to relist two Merck patents on Zocor. According to the court, by denying the citizen petitions, the FDA effectively nullified Ivax’s and Ranbaxy’s rights to 180-day exclusivity periods, contrary to the clear intent of Congress.
In 2000 and 2001, Ivax and Ranbaxy filed ANDA’s for generic versions of Zocor, a blockbuster statin drug, certifying under paragraph iv that two of Merck’s Orange Book listed patents were invalid, unenforceable, or not infringed. However, Merck chose not to sue the generic drug companies for patent infringement. In 2003, Merck sent a letter to the FDA requesting that the two patents be removed from the Orange Book. The next year, the FDA delisted the two patents.
In 2005, Ivax and Ranbaxy submitted citizen petitions asking the FDA to relist the patents, and for confirmation that, as the first ANDA filers, they were still entitled to 180 days of marketing exclusivity for generic Zocor. In October, 2005, the FDA denied the petitions, stating that it would not relist the patents and that no generic applicant would be entitled to a 180-day exclusivity period. In denying the citizen petitions, the FDA asserted that the statute was ambiguous, and therefore it was free to choose how to handle delisting requests.
On summary judgment, the U.S. District Court for the District of Columbia, Judge Richard W. Roberts, held that the FDA was wrong to deny the citizen petitions. According to the court, the issue in the case was "whether the FDA can effectively restrict the reward [of a 180-day exclusivity period] to only a sued ANDA holder by delisting a patent after the ANDA holder successfully avoided suit." The court observed that if the FDA had not delisted the patents, Ivax and Ranbaxy would have been entitled to the exclusivity period, triggered by their commercial marketing of generic Zocor. Additionally, the court noted that pursuant to FDA regulations the FDA will not delist a patent once litigation has ensued. The court concluded as follows:
If Merck had sued plaintiffs because of their paragraph IV certifications, plaintiffs would have been in danger of losing their right to a 180-day exclusivity period upon final FDA approval only if the patents were found to be enforceable or infringed. In this case, however, the FDA delisted the patents from the Orange Book, disregarding the plaintiffs’ success in avoiding suit. That disparate treatment here contravened the plain and undisputed intent of Congress. The delisting practice as applied here effectively eliminated Congress’s "first commercial marketing" trigger, in violation of the clear command of Congress.
The FDA has not yet indicated whether it will appeal the decision to the D.C. Circuit.
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