Lilly ICOS is celebrating after the European patent office affirmed an earlier decision revoking Pfizer’s method of use patent for Viagra (sildenafil) in the treatment of erectile dysfunction, which the world’s largest pharmaceutical company had used to try and block sales of Lilly’s Cialis (tadalafil).
The ruling was made following a three-day hearing, and Lilly ICOS says it “makes it clear that Pfizer is not entitled to exclusivity in the area of oral PDE5 inhibitors for [ED] in many of the countries in Europe.”
Back in 2002, Pfizer was awarded a supplemental US patent for Viagra [[24/10/02e]], broadly covering the use of orally effective phosphodiesterase type 5 inhibitors for the treatment of ED, providing patent protection for Viagra in the US until 2019. The basic patent excluded others from making, using or selling the active ingredient for Viagra until 2011. Pfizer subsequently filed lawsuits against Eli Lilly and partner ICOS, and Bayer and GlaxoSmithKline, asserting that their PDE-5 inhibitors, Cialis and Levitra (vardenafil) respectively, infringed the new patent.