Agenix said it had filed an international method of manufacture patent application under the Patent Cooperation Treaty (PCT) for its hepatitis B drug AGX-1009. The application covers the manufacturing process of a compound that uses the same active ingredient, Tenofovir, used in the US Food and Drug Administration (US FDA) approved drug marketed by Gilead Sciences under the trade name Viread.

The international application aims to provide further long-term protection for the company’s platform hepatitis B drug compounds through until 2030. Agenix already has a registered patent to protect the AGX-1009 compound in China through to 2026. Like Viread, AGX-1009 is a so-called ‘prodrug' of Tenofovir. Gilead’s ‘prodrug’ of Tenofovir was approved for treatment of hepatitis B in the US in 2008 and in numerous countries globally but is not yet approved in China. Both drugs contain Tenofovir but have different molecular side chains to activate that compound. Both drugs work by blocking an enzyme the hepatitis virus needs to replicate.

Agenix will initiate a phase I human safety trial of AGX-1009 in 2012. The clinical trial application will be made with assistance from the Institute of Medicinal Biotechnology (IMB) of the Chinese Academy of Medical Sciences in Beijing, from whom Agenix purchased the original compound patent.

AGX-1009 is one of several new drug candidates supported by the Chinese Government’s State Special Funds for important new drugs which aims to expedite new mass market therapies for major diseases in China. Gilead's version is expected to be released on the Chinese market in 2014.   

Agenix chairman and chief executive officer Nicholas Weston said, “This important patent application confers further certainty in China and increases the commercial value of this promising treatment for hepatitis B in geographies outside of China.” “Agenix's patents are a major asset and value for future strategic commercial partnerships. We continue to expand our patent portfolio which is fundamental to our future commercial licensing, clinical development and strategic business partnerships with global pharmaceutical companies,” he said.

Patent Cooperation Treaty (PCT) applications allow applicants to file in a standard English-language format and provide wide protection in multiple international markets.