Jun 012015
 

imak logo[Initiative for Medicines, Access & Knowledge, Link, (CC-BY)] Worldwide 150 million people are living with Hepatitis C. In countries like Argentina, Brazil, China, India, Ukraine and Russia 59 million people have Hepatitis C, and worldwide 700,000 people are dying preventable deaths from liver cancer and liver disease.

Pharmaceutical corporation Gilead Sciences is seeking illegitimate patents for the hepatitis C medicine sofosbuvir, blocking millions of people around the world from getting the treatment they need to get well. If Gilead is awarded unjustified patents in Argentina, Brazil, China, Ukraine and Russia, based on the likely prices that will be set for these countries, they could be faced with an overspend of US$270 billion to treat all people with hepatitis C.

Building on the patent challenges which I-MAK filed in India with the Delhi Network of Positive People and helped Médecins du Monde file last year in Europe, I-MAK has now filed a patent challenge in China and also worked with its partners, Fundación Grupo Efecto Positivo (Fundación GEP) of Argentina, Grupo de Trabalho sobre Propriedade Intelectual (GTPI) of Brazil, Treatment Preparedness Coalition of Russia and the All-Ukrainian Network of People Living with HIV/AIDS of Ukraine who have filed a series of new co-ordinated patent challenges in recent weeks in their respective countries. This collective action could have major implications for the global fight against an exploding hepatitis C epidemic.

Legal Grounds of the Patent Oppositions

Patent Claming the Active Ingredient (Base Compound)

Oppositions on the base compound have been filed in Brazil and India. The key grounds are:

  • Novelty: The drug is not new. The base compound has been disclosed in various earlier patents, which already disclose the base compound that is used in sofosbuvir(1).
  • Inventive step: The patent application is for old science, and patents should not be granted to products that are based on well-known techniques that are obvious to try. In addition to the earlier patents that reveal the base compound used in sofosbuvir, additional patents and literature would have made obtaining these compounds obvious to a person skilled in the field (2).
  • In India, India’s Patents Act stipulates that new forms of known substances have to demonstrate that they enhance the therapeutic efficacy of the product in order to deserve a patent. This clause, known as Section 3 (d), was designed to clamp down on evergreening, a standard industry practice whereby companies apply for patents on minor changes to existing drugs and compounds. Gilead’s patent application covers a new form of 2’-modified nucleoside analogs, which already exist in the field and are classified as derivatives. Gilead Sciences has not provided evidence in its application that shows that these derivative compounds have enhanced efficacy over known forms.
  • The patent document describing the invention is not sufficient, and therefore does not fully comply with patent law requirements.

Patent Claiming the Marketed Compound (the Prodrug)

Oppositions on the prodrug have been filed in Argentina, China, Europe (covering 38 countries that are a member of the European Patent Convention), India and Russia.

  • Inventive step: The pro-drug form in Gilead/Pharmasset’s application was already disclosed in an earlier 2005 application by the University of Cardiff for the treatment of cancer and a research article by Perrone et al. for a compound and it’s prodrug used for treating hepatitis C. Several other exhibits included with the oppositions demonstrate how the “ProTide” pro-drug method had been used repeatedly in the past for drugs. The patent application is, therefore, for old science, and patents should not be granted to products which are based on well-known techniques that are obvious to try.
  • India’s Patents Act stipulates that new forms of known substances have to demonstrate that they enhance the therapeutic efficacy of the product in order to deserve a patent. The pro-drug step represents a new form of a known substance, and Gilead/Pharmasset’s patent application provides no data demonstrating enhancement in therapeutic efficacy over the free base compound.

Patent for the Intermediate Compound and Process for Making Sofosbuvir

As patent applications for the base active compound and the prodrug were not filed in the Ukraine, a patent challenge was made against a patent application that covers the intermediate compound and process for making sofosbuvir. This challenge is to ensure the patent does stand in the way of local producers being able to make generic versions.

The grounds of the challenge are being translated and will be available shortly.

Notes:

(1) In particular, patent WO2002/057425
(2) For example, earlier documents discuss 2’-modified nucleoside analogs, their prodrugs and pharmaceutical compositions. Sofosbuvir is based on 2’-modified nucleoside analogs with substitutions that have already been revealed or would have been minor changes to someone skilled in the field. Furthermore, as far back as 1996, literature shows that using 2’-modified nucleoside analogs, including uridine nucleoside derivatives as antiviral compounds would be useful. Gilead/Pharmasset use a uridine derivative nucleoside for the free base compound application for sofosbuvir.

Click here for a printable PDF from i-mak.org.

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