Orexo, AB v. Actavis Elizabeth LLC

Orexo, AB (defendant) owned a patent on Zubsolv, a drug used to treat opioid dependence. The patent was known as the ‘330 Patent. Like prior drugs, the ‘330 patent called for a combination of buprenorphine, naloxone, and citric acid. However, the ‘330 Patent offered a different formulation from prior drugs such as Suboxone. The ‘330 patent used citric-acid particles as a carrier for buprenorphine particles, which other drugs had not done. Clinical trials showed that the ‘330 Patent increased the bioavailability of buprenorphine and thus improved the effectiveness of Zubsolv relative to existing drugs. Orexo also demonstrated that the formula in the ‘330 Patent would deter abuse of Zubsolv. Abuse was a major concern among the producers of similar drugs. Actavis (plaintiff) filed for a generic version of Zubsolv and challenged Orexo’s patent. Actavis argued that the formulation in the ‘330 Patent was obvious because each aspect of the formulation was referenced in prior art. The trial court ruled in favor of Actavis, holding that all the ingredients in the ‘330 Patent were generally known. The court stated that although the specific formulation was not shown or suggested in any reference, Orexo’s combination would have been obvious to a person of ordinary skill. The trial court also cited the existence of a patent owned by the makers of Suboxone, known as the ‘832 Patent. The ‘832 Patent included using citric acid to increase bioavailability. Additionally, the court cited several other patents that included components of the ‘330 Patent. Orexo countered that there was no other reference of citric acid as a carrier particle. Orexo appealed the case.