Date: 21 January 2019
By Lucy Holt
Truvada is a critical drug used for the prevention and treatment of HIV. It is also used for HIV pre-exposure prophylaxis (PrEP), which can reduce, by up to 92%, the risk of HIV infection in people who are at high risk. Truvada is a combination of two active ingredients - tenofovir disoproxil (TD) and emtricitabine. TD alone is sold as Viread and is used to treat chronic hepatitis B and to treat and prevent HIV.
Gilead is a biotech company that researches, develops and commercialises drugs, including TD and Truvada. Gilead’s key patent for TD expired in July 2017 in most jurisdictions.
In an attempt to prolong their market exclusivity, Gilead applied for supplementary protection certificates (SPCs) for the combination product, Truvad. SPCs were granted in the UK, France and Switzerland. (The combination product has been available since expiry of the patent in the Netherlands, Italy and Greece, where the SPC application was rejected).
The UK High Court has now ruled that Truvad was not “protected by the basic patent [for TD]” and thus Gilead’s Truvad SPC was invalid. Consequently, generic versions of Truvada can now be manufactured and sold in the UK.
The UK High Court earlier referred a question to the Court of Justice of the European Union (CJEU) regarding the interpretation of the wording “protected by a basic patent” of Article 3(a), Regulation (EC) No 469/2009. The CJEU published its decision in C-121/17 on 25 July 2018, in which it indicated (paragraph 56) that Gilead’s Truvad SPC did not fulfil the condition set out in Article 3(a) Regulation (EC) No 469/2009 because “the basic patent at issue contains no information as to the possibility that the invention covered by that patent could relate specifically to a combined effect of TD and emtricitabine … for the purposes of the treatment of HIV.”
In the decision, the CJEU introduced a new test for whether a product consisting of a combination of active ingredients is “protected by a basic patent in force”.
The Court held that in order for the patent claims to “relate necessarily and specifically” to the combination, through the eyes of the skilled person, accounting for the prior art at the filing date or the priority date of the patent, the following criteria must be satisfied:
The CJEU decided that it did not seem possible for the skilled person to understand how the combination of emtricitabine with TD falls under the invention covered by the patent, because the claims did not relate to emtricitabine.
Following the result of the CJEU referral, Mr Justice Arnold of the UK High Court ruled, on 18 September 2018, that Gilead’s Truvada SPC was invalid for the reasons indicated.
A question may be raised regarding why Gilead did not apply for an SPC for the TD drug alone (Viread). The reason for this is that the regulatory approval and thus the marketing authorisation was obtained so quickly after the filing date of the patent, that the effective term of an SPC would have been zero.
You can find this article and others in our Patent Issues Newsletter Spring 2019.