The expiration of drug patents means generic companies are free to manufacture the same compound. But, the patent holder can circumvent this by introducing a modification to the drug. Such an action is called 'evergreening' and allows companies to take advantage of loopholes in the patent and regulatory system to legally extend the monopoly of a product way past its expiry.
The FDA is to respond to Orchid's CP within two months but no one from the company was available to make any comments on the progress. Orchid Chemicals and Sandoz filed Citizen's Petitions (CP) to the FDA in October 2006 and November 2005, respectively, while Abraxis Pharma did not file its own petition but tagged along with Sandoz's, according to Wyeth.
Wyeth explains that a new patent, a re-formulated version of Zosyn, was filed in October 2005 and claims that the re-formulation was done to comply with the most recent US Pharmacopeia particulate standards. Thus, Wyeth has extended its Zosyn patent until 2023.
Zosyn, an intravenous antibiotic for serious infections, recorded sales of more than $760 million and grew by 19 percent, making it the fastest growing injectable antibiotic worldwide, according to Wyeth.
"These petitions request FDA to determine that the original Zosyn formulation was not discontinued for safety and efficacy reasons, and ask FDA to accept ANDAs based on the previous formulation," Natalie de Vane, a spokesperson for Wyeth, told US-PharmaTechnologist.com.
It is possible for anyone, also pharmaceutical companies, to request or petition FDA to alter or generate an agency policy or regulation. In return, the FDA is required to respond within 180 days, where the request is either given as approved, denied or undecided.