Allergan settles Restasis litigation with Pfizer's InnoPharma as backlash mounts over tribal patent deal

Even as it is under intense fire for its controversial tribal licensing agreement on blockbuster Restasis, Allergan on Thursday inked a settlement for the eye med that gets one more would-be generic challenger off its radar, for now.

Allergan and Pfizer's InnoPharma entered a settlement that will allow the latter company to market a generic version of Restasis in February 2024 or earlier under certain undisclosed circumstances. Allergan will also allow InnoPharma to sell an authorized generic in August 2024 if InnoPharma hasn't notched FDA approval for its copycat version by then.

The companies didn't offer any other details on the arrangement. According to FDA's Orange Book, Allergan's patents on Restasis expire on Aug. 27, 2024.

With that considered, the deal "speaks to the strength of Allergan's IP protection around Restasis" because the generic launch date is so close to Restasis' actual patent expirations, Wells Fargo analyst David Maris wrote in a note Thursday evening.

The drugmaker has not been acting as if its Restasis patents are ironclad. Allergan entered its controversial licensing deal with the Saint Regis Mohawk Tribe last month, agreeing to transfer Restasis patents and license them back to defend against a type of challenge called an inter partes review at the U.S. Patent and Trademark Office. But the current settlement relates to another fight over Restasis' IP in federal court in Texas.

Because Allergan is fighting separate and simultaneous patent challenges, it's argued the current review landscape is "flawed" and amounts to a "double jeopardy." With the new settlement, Maris wrote that only three challengers remain in the federal court case: Mylan, Teva and Akorn.

If any of Allergan's opponents are able to strike down Restasis patents before the 2024 expiration dates, it will endanger billions in Allergan sales. At earliest, though, Maris wrote that generics shouldn't arrive before 2019.

Thursday's settlement follows another deal Allergan made in August with Famy Care that established a February 2024 launch date for that company's potential generic.

On the IPR challenge, Allergan's tribal licensing agreement seeks to use the sovereign immunity argument to sidestep a patent attack at the PTO. It remains to be seen whether the strategy will work as it's generated a wave of criticism and attracted considerable attention in Congress.

Responding to all of the backlash, the chiefs of the Saint Regis Mohawk Tribe wrote to Congress on Thursday to explain their motives. They said the tribe's current revenue streams are flatlining and that expenses are growing, forcing them to explore new funding options.

Further, they said, IPR reviews "allow repetitive attacks on patents, lack finality and due process, and use legal standards that are systematically unfavorable to patentees," reiterating arguments Allergan CEO Brent Saunders has made in defense of the deal.