The High Court of England and Wales has ruled that Pfizer’s patent protection for pregabalin in the UK is invalid and not infringed by Actavis’ copycat drug, throwing a big question mark over the strength of so-called second medical use patents.

Pfizer’s original patent for pregabalin (sold as Lyrica) as a treatment for epilepsy expired last year, paving the way for Actavis and others to launch cheaper generic formulations.

However, the firm secured a second-use patent protecting pregabalin as a treatment for pain until July 2017. In the complex and closely-watched legal case, Pfizer argued that Actavis’ generic alternative would inevitably be used to treat pain despite targeting non-protected indications, and thus infringed on its patent. 

As well as taking Actavis to court, Pfizer obtained an order against NHS England compelling the NHS to issue guidance that only its branded product should be prescribed for pain, and the drugs giant also sent letters to doctors and pharmacists threatening legal action if they did not comply.

Threats 'unjustified'

However, High Court Judge Richard Arnold did not agree, ruling the patent to be invalid and not infringed by Actavis. He also stressed that threats to medical professionals over correct prescribing of pregabalin were unjustified.

Tim Powell, partner at Powell Gilbert LLP, which represented Actavis, said the judgment “provides welcome clarity in a very complex area of the law”, but the court has also urged the Department of Health to put in place a system that minimises the potential for future disputes surrounding second medical use patents.

Pfizer said is disappointed with the decision and intends to appeal the ruling.

“We know through our experience with the Lyrica situation that the absence of any national policy or framework for second medical use patents in the UK has been a cause of concern and confusion for many, including us,” Berkeley Phillips, Pfizer UK Medical Director, told PharmaTimes Digital.