Patent revoked on Tenofovir

US patent office?s move to revoke patents on key HIV/AIDS drug could mean increased access in developing world

In a move that could have major implications on access to a cornerstone HIV/AIDS medicine across the developing world, the U.S. Patent & Trademark Office on January 23, 2008 revoked four key patents held by the pharmaceutical company Gilead Sciences on the drug tenofovir disoproxil fumarate (TDF).

The public interest group Public Patent Foundation (PUBPAT), which challenged the patents in the US, submitted evidence that TDF was already a known substance at the time of Gilead’s application for the patents, and therefore a patent should not have been granted. The evidence used in the patent office’s ruling may have an impact on whether the drug will be granted patents in other countries, such as India and Brazil.

The fact that this patent was revoked in the US also shows that existing patents have been granted for drugs that have not met patentability standards, and can in fact be invalid. It also shows the importance and effectiveness of interested parties opposing patents in the interest of public health.

In India, the Indian Network for People Living with HIV/AIDS opposed Gilead’s patent application in May 2006 on similar grounds to PUBPAT’s challenge in the US. The evidence on which the US based its decision could therefore lead to the Indian patent office rejecting the patent application. Similarly, in Brazil, a patent opposition filed by HIV/AIDS groups and a government pharmaceutical laboratory could also mean a patent might not be granted for TDF in Brazil.

If a patent is not granted in these countries, generic manufacturers could freely manufacture and export generic versions of TDF without restrictions, leading to greater competition and therefore lower prices.

In addition, should Gilead’s patent application be rejected in India, the voluntary license agreements that the company has already signed with most Indian generic manufacturers would be put into question.

The WHO treatment guidelines for HIV/AIDS recommend the use of TDF in first and second-line ARV treatment, and several MSF projects have started using TDF as part of a less-toxic first-line regimen.