Earlier this week the California, US firm announced its fifth Narcan nasal spray patent - no. 9,629,965 covering formulation, delivery and use of the four-milligram version of the product - had been listed in the US FDA Orange book.
A listing means firms seeking approval for to sell generic versions of the spray must inform Opiant and its partner Adapt Pharma Limited of their intention.
According to Opiant the required notification “would be subject to a 30-month stay of marketing approval and potentially longer if such notification occurs and a patent infringement suit is successful.”
CEO Roger Crystal said: “We now have five Orange Book-listed patents for Narcan and are encouraged by our solid intellectual property position and enhanced product exclusivity.”
He added that: “This latest patent also has the potential to be valuable for some of Opiant’s additional programs.”
Opiant and its partner Adapt Pharma Limited are seeking to strengthen their IP portfolio under the looming threat of competition.
Last September, Adapt announced it had received notice from Teva Pharmaceutical Industries of an ANDA filing seeking approval to market a generic version of Narcan before the expiration of US Patent No. 9,211,253.
Adapt and Opiant accused Teva of patent infringement. The case is ongoing.
In January this year Teva notified Opiant and Adapt it had filed a second ANDA seeking approval to market a generic version of Narcan nasal spray before the expiration of U.S. Patent No. 9,468,747 in 2035.
The active pharmaceutical ingredient (API) in the Narcan nasal spray is naloxone, a generic opioid antagonist that reverses the central nervous system and respiratory system depression caused by opioids.
Various injectable versions of the drug are available in the US supplied by firms including Amphastar, Pfizer’s unit Hospira, Mylan and West-Ward.
In 2014, Kaleo won approval for Evzio, a version of a drug delivered using an autoinjector. According to a study published in the New England Journal of Medicine (NEJM) Evzio now costs $4,500 per two-syringe pack, up from the launch price of $690.
Narcan nasal spray – which was approved in 2015 – costs $150 for two single-use devices.