A medical charity scored a small victory Wednesday in its bid to break a US pharma giant's hold on an eye-wateringly expensive Hepatitis C drug when a European body partially revoked the firm's patent.
Patient groups around the world have accused Gilead Sciences of charging exorbitant prices for its blockbuster sofosbuvir drug, which is highly effective but can cost up to $1,000 per pill.
In France, a 12-week course of treatment costs 41,000 euros ($46,000).
To open the way to a low-cost generic version of the drug, sold under the brand name Sovaldi, the group Medecins du Monde (Doctors of the World) had launched a legal challenge against the firm's patent.
Ruling on the claim, the European Patent Office in Munich said it had upheld the patent filed by Gilead but "in an amended form", leaving only the components used in the drug under intellectual protection, not sofosbuvir itself.
The MdM charity said the impact of the ruling was difficult to interpret but it at least created a legal limbo that could give European governments leverage to renegotiate prices with Gilead.
"It's an interesting decision for us even if the patent wasn't revoked as we had hoped," said MdM drug pricing campaign manager Olivier Maguet.
"This creates a weak legal position for the drug and so allows governments to take back the reins a bit in the negotiations with manufacturers," he told AFP.
Gilead, in a statement, said it was "pleased that the patent has not been revoked". It did not make any mention of amendments to the European patent.
The drug, which cures 90 percent of Hep C cases, has brought hopes to millions, but critics say Gilead has priced it out of the reach of many patients and public health systems.
In its legal filing, Doctors of the World had argued that Gilead did not deserve the patent because the science behind the drug was not sufficiently innovative and relied on advances made by other private and public researchers.
Faced with a global chorus of criticism over its high prices, the company entered into licensing agreements with several firms in 2014 that allowed them to produce cheaper versions of the drug in developing countries.
In India the treatment costs around 220 euros, MdM says.
Hepatitis C, a blood-borne viral disease, affects 130 to 150 million people globally and can result in liver cirrhosis or cancer.
According to the World Health Organization, it is responsible for 700,000 deaths yearly.
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