Pharma firm loses patent suit to stop generic HIV drug

A pharmaceutical firm has lost its appeal aimed at preventing two companies who make and supply generic drugs from putting any product on the Irish market which contains a combination of two particular anti-retroviral agents. 

 

The Court of Appeal on Tuesday dismissed an appeal by Gilead Sciences against a High Court decision revoking its supplemental protection certificate for Truvada, a combination therapy used to treat HIV. 

 

Gilead Sciences Inc and Gilead Biopharmaceutics Ireland brought proceedings against Teva and Norton (Waterford) Ltd, trading as Teva Pharmaceuticals Ireland, and against Mylan SAS, Generics UK Ltd (trading as Mylan) and McDermot Laboratories Ltd, trading as Gerard Laboratories Ltd and as Mylan Dublin. 

 

The case concerned Truvada, a combination therapy drug developed by Gilead which contains two anti-retroviral agents – tenofovir disoproxil (TD) and emtricitabine (FTC). 

 

Gilead claimed Truvada had the benefit of a supplemental protection certificant – essentially an extension of patent protection – granted by the Controller of Patents under an EC Regulation in August 2009, which had been due to expire on February 20th 2020. 

 

It claimed the certificate would be infringed if the Teva and Mylan defendants, involved put any product on the Irish market containing a combination of the drugs. The case centred on the validity of the certificate. 

 

In an October 2019 judgment, Mr Justice Denis McDonald rejected Gilead’s claims about the validity of the certificate. He agreed with the defendants the drug combination was not protected by the relevant patent. 

 

He noted evidence the patent is relevant to not just HIV but to a number of important viruses and had “very good activity” against hepatitis B and did not accept Gilead’s claim that HIV is the principal or most important focus of the patent. 

 

He made subsequent orders revoking the certificate and dismissing Gilead’s case. 

 

On Tuesday, the three judge Court of Appeal upheld the High Court findings. 

 

Giving judgment, Ms Justice Caroline Costello said the trial judge had, in his “exemplary” judgment, engaged with the essential evidence and arguments advance by Gilead and had clearly set out his reasons for rejecting those. 

 

Gilead’s submission that he effectively ignored evidence as to the urgent unmet clinical need to deal with HIV in 1996, the priority date of the patent, was “untenable”, she said. He was clearly fully aware of the AIDS crisis and had set it out in detail in his judgment. 

 

Gilead’s “true complaint” was that he also gave weight to the clinical need in relation to other viral infections, particularly hepatitis B, but also herpes and cytomegalovirus among others, she said. Given the expert evidence, his approach was “unimpeachable”, she said. 

 

She rejected arguments that the trial judge erred in his approach to construing the patent and held he correctly construed it in accordance with EU and domestic law. 

 

The trial judge construed the patent through the lens of a correctly identified “skilled team” of a medicinal chemist and a clinician who would be involved in managing a range of viral infections including herpes, hepatitis B and HIV, she said. 

 

Having done so, the trial judge concluded the patent was not primarily focused upon developing treatment for HIV and was a “broad” patent concerned with developing treatments for other viral infections such as herpes, hepatitis B and cytomegalovirus, all of which were of significant clinical concerns in 1996. 

The patent was not directed solely towards treating HIV, she said. Because FTC was not expressly claimed in the patent, the High Court correctly held the certificate was not protected by the basic patent in force with the effect the certificate was properly revoked.