In May 2013, FDA responded to a manufacturer-submitted citizen petition regarding the opioid Opana® (Oxymorphone Hydrochloride), determining that its original crushable formulation of the product was not withdrawn for safety reasons. FDA’s decision meant that currently marketed generic versions of the original Opana may remain on the market and that FDA may approve additional Abbreviated New Drug Applications (ANDAs) referencing Opana in the future.
The Opana decision was notable given that FDA reached the opposite conclusion regarding a different opioid in April 2013, when it determined that the original crushable form of OxyContin® (Oxycodone Hydrochloride) was withdrawn from the market for safety reasons. At that point, FDA decided not to approve generic versions referencing original OxyContin given the availability of a new tamper-resistant formulation of the product.
FDA’s opinion on Opana is consistent with its 2011 determination, which specified that two dosage strengths of original Opana were not withdrawn for safety reasons, and therefore FDA did not act to block Opana generics before patent expiry in January. Though FDA’s determination is final, Opana’s manufacturer can conduct further studies and attempt to collect data that FDA indicates is necessary to prove abuse-deterrence, then file another citizen petition.
The implications of FDA’s decisions on Opana and OxyContin are significant. These developments suggest that FDA will proceed very carefully on a case-by-case basis in determining whether a generic drug that references a non-tamper-resistant version of an innovator product can be legally marketed, particularly after the innovator withdraws its non-tamper-resistant product and begins marketing a new formulation with tamper-resistant protection.
FDA’s recent decisions suggest that a manufacturer withdrawing an innovator product in order to market a reformulated, tamper-resistant version may be able to do for safety reasons, and make it impossible for a generic to the original version to be approved. This could impact competition from manufacturers of generics. Branded manufacturers considering product reformulations to incorporate abuse-deterrent technologies are encouraged to re-examine the precedents FDA established in the cases of Opana and OxyContin, as this will enable them to gauge the advantages and disadvantages of product reformulation. These precedents can provide a blueprint for the type of data FDA may require from branded manufacturers attempting to demonstrate that a product withdrawal occurred due to safety reasons. Generic manufacturers may also draw on such precedents when attempting to counter arguments that product withdrawal resulted from safety concerns.