Brazil’s National Institute of Industrial Property (INPI) has rejected a patent on Gilead’s version of tenofovir, one of the most commonly used antiretroviral drugs, following a lengthy investigation. The decision looks set to intensify debate over the effects of intellectual property laws on access to medicines.
Previous disputes over access to medicines have focused on the use of compulsory licences to import generic versions of patented products.
Recently there has been a greater focus on overturning patents on medicines or preventing the grant of patents in India, where most of the world's generic versions of antiretrovirals are manufactured. India has become a major generic manufacturer as a result of a lack of patent protection for specific drugs prior to 2005. New legislation has made it possible for new drugs, discovered recently, to be patented in India - but only if they represent genuine innovations.
For example, while the first integrase inhibitor raltegravir has received a patent in India, a patent application for the protease inhibitor atazanavir was rejected because it was not considered to represent an innovation under Indian law.
In the United States the patenting of tenofovir was rejected by the US Patent and Trademarks Office following a complaint by the Public Patent Foundation. They argued that Gilead Sciences had not revealed prior knowledge that would have invalidated the original patent request. Gilead appealed against the US patent rejection, and the patents were restored.
Gilead’s patent has been opposed in a number of countries on the grounds that the fumarate salt form of tenofovir (tenofovir disoproxil fumarate) is not an innovation, already being present in a number of other pharmaceutical agents.
In Brazil Gilead sought a patent for tenofovir disoproxil fumarate rather than tenofovir disoproxil, the intermediate ingredient. In the US a patent for this intermediate ingredient has been upheld.
Gilead now has 60 days to appeal against the Brazilian decision, but its chances of success are thought to be lower than in the US case. This is because Brazil’s Ministry of Health has declared tenofovir to be a medicine of public interest, reflecting the fact that over 31,000 people with HIV in Brazil already receive the drug at a cost of $43 million a year – around 10% of the country’s total antiretrovirals budget.
Brazil’s Ministry of Health has signalled that it is looking to reduce the amount it spends on tenofovir, either by negotiating a lower price from manufacturer Gilead, by importing a generic version from India or eventually manufacturing the drug in Brazil.
Brazil’s government negotiated a reduction of tenofovir’s price with Gilead Sciences in 2006. That agreement is due for re-negotiation soon.
Brazil’s Secretary of Science, Technology and Strategic Products from the Ministry of Health, Reinaldo Guimarães, told O Estado de São Paolo newspaper this week: "We will certainly ask for a lower price compared to what is charged today: US$ 3.25 a dose."
In comparison generic versions are available from Indian companies at around US$0.40 per dose.
However, Indian companies with voluntary licences from Gilead are specifically prohibited from exporting to Brazil under the terms of their agreements. The only major antiretroviral manufacturer not to seek a licence from Gilead, Cipla, is awaiting WHO prequalification for its own version of tenofovir, and could profit handsomely, according to the Initiative for Medicines, Access and Knowledge, a US non-profit organisation that provides technical assistance to challenge patent restrictions on access to medicines.
The Brazilian government has already replaced the branded version of efavirenz (Stocrin) with a generic version following a refusal by manufacturer Merck to reduce the price by 60% in 2007.