Federal Circuit upholds AzaSite eye drop patents
The US Court of Appeals for the Federal Circuit has upheld the validity of four patents covering conjunctivitis treatment AzaSite (azithromycin ophthalmic solution).
The court agreed with the US District Court for the District of New Jersey that Sandoz, which sought to make a generic version of AzaSite, had not shown that the four patents in the lawsuit were invalid on the grounds of obviousness.
Pfizer owns one of the patents, US number 6,861,411, called “method of treating eye infections with azithromycin,” which it has licensed exclusively to eye drug maker InSite Vision. It is due to expire on November 25, 2018.
InSite owns the other three patents, which claim formulations and methods of using topical azithromycin as an eye drop solution for treating eye infections. Those patents will expire on March 31, 2019.
InSite licensed all four patents exclusively to Inspire Pharmaceuticals, which marketed AzaSite in the US. Inspire has since been acquired by Merck Sharp & Dohme.
InSite, Inspire and Pfizer sued Sandoz in 2011 after it filed an Abbreviated New Drug Application at the US Food and Drug Administration seeking approval to make and sell a generic version of AzaSite.
Sandoz later argued that the patents were invalid as obvious. In 2013, the district court disagreed and upheld the patents. Sandoz appealed against the decision, arguing that the district court had framed the question of obviousness too broadly.
It said that rather than considering whether it was obvious to develop a topical ophthalmic solution containing the AzaSite active ingredient azithromycin, the court should have asked a narrower question—whether it was obvious to develop such a solution for the treatment of conjunctivitis.
The Federal Circuit, in its April 9 decision, agreed with the district court’s framing of the question. It found that the court had properly considered the evidence in its finding that the ’411 patent was valid, and agreed that “even in the light of the ‘411 patent”, the other three patents were not obvious.
Circuit Judges Sharon Prost, Pauline Newman and Richard Linn affirmed the court’s ruling on the four patents’ validity.
InSite did not respond to LSIPR’s request for comment. Sandoz declined to comment.
A spokesman for Pfizer, which was named in the 2011 lawsuit, said: "Other than being named as a party because we own one of the patents in suit, Pfizer does not have any involvement in this case."
