Tenofovir disoproxil fumarate – TDF

Tenofovir disoproxil fumarate is recommended by WHO as a component of the first-line antiretroviral treatment regimen, and as an alternative component of second-line regimens for adults. It is also recommended as a component of alternative first-line and second-line treatment regimens for children over three years of age. Tenofovir disoproxil fumarate is also commonly known as TDF.

Summary

With limited exceptions (notably China and Mexico) there appears to be robust market competition for tenofovir in low and middle-income countries. Market competition may be limited for some generic TDF-containing combinations, in countries outside the 112 territories licensed under the Medicines Patent Pool.

Patent status

The compound patent on tenofovir was filed by the Czech Academy of Science in 1985 and has expired in most (if not all) jurisdictions where it was granted.

The patents on the disoproxil ester and the fumarate salt are due to expire in 2017 and 2018 respectively. On the basis of available information, these patents have been granted only in China, Indonesia and Mexico and were either not filed or were rejected in most other low- or middle-income countries. A process patent has been granted in India.

Licensing status

Tenofovir disoproxil fumarate has been licensed to several antiretroviral drug manufacturers with a geographical scope of 112 countries. In 2011, it was licensed to the Medicines Patent Pool (MPP) and the detailed terms and conditions of that licence are publicly available. As a result of the unbundling provisions in the MPP/Gilead licence, generic manufacturers that have taken the MPP licence and made use of that flexibility, have been able to supply to additional low-income countries in which tenofovir disoproxil fumarate is not patented.

Indonesia issued a compulsory licence on tenofovir and its combinations with FTC and FTC/EFV in 2012.

Combinations

There are several approved combinations that contain tenofovir, such as TDF/FTC, TDF/3TC, TDF/3TC/ EFV, TDF/FTC/EFV and TDF/FTC/RPV. Patent applications relating to one or more of these combinations have been granted in ARIPO member states, China, EAPO member states, Indonesia, Mexico, OAPI member states, Philippines, South Africa, Turkey, Ukraine and Viet Nam, and are pending in Argentina, Brazil, India, Malaysia, OAPI member states, Thailand and Venezuela. While licenses or “covenants not to sue” on TDF, FTC, TDF/FTC, TDF/FTC/EFV and RPV cover 112 countries, the sale of generic versions of the combinations may be delayed outside those countries as a result of patents on the individual compounds or on the combinations.