Indian Patent Office rejects Pfizer's claim for arthritis drug patent

The Indian Patent Office has rejected a patent application by pharma multinational Pfizer Inc for its rheumatoid arthritis drug `Tofacitinib' as the US firm failed to substantiate its claim by establishing the enhanced efficiency of the compound over its base version.

''After having considered the submissions submitted by the applicant (Pfizer) in the hearing, the written submission and amended claims filed as well as in view of the discussions and findings by me, it is hereby ordered that the invention disclosed and claimed in the instant application is not considered as an invention under the provisions of the Act'', said Bharat N S, assistant controller of patents & designs, Mumbai.

''For the purposes of this clause, salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations and other derivatives of known substances shall be considered to be the same substance, unless they differ significantly in properties with regard to efficacy,'' he said.

Quoting an apex court judgment, the assistant controller said that the applicant will have to establish the therapeutic enhanced efficacy of the claimed compound over the base compound. 

''For the purposes of this clause, salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations and other derivatives of known substances shall be considered to be the same substance, unless they differ significantly in properties with regard to efficacy,'' he said.

This is the second time a multinational drug maker seeking to enforce its intellectual property rights in the country has failed to make it.

In  November 2012,  the Intellectual Property Appellate Board (IPAB) revoked the patent on Roche's drug 'Pegasys' (pegylated interferon alfa-2a), a biologics preparation used to treat Hepatitis C, seven years after it was granted by the Indian Patent Office in 2005 (See: Roche's patent on Hepatitis C drug set aside).

According to Pfizer, the company has sought a patent that covers an important chemical formulation of the active compound in the medicine.

The Patent Office, however, said the company would have to establish that the compound for which it is seeking a patent is therapeutically more effective than the active compound originally used in the medicine.

"The invention disclosed and claimed in the instant application ... is not considered as an invention under the provisions of the Act," the assistant controller at the patent office wrote in an order dated 3 September.

Pfizer, which is seeking to hold on to trademark rights of its patented drugs beyond patent expiry through "evergreening" or making cosmetic changes in the compounds, said it is reviewing options for further action.

Generic equivalents that limit the active life of patented drugs have become a thorny issue for multinational drug makers seeking to expand market in emerging and developing countries.

Companies including Pfizer, Bayer and Roche have in recent years struggled to retain exclusivity on drugs in India, alleging that patent laws are designed to favour local industry.

India, however, claims its patents policy is designed to ensure affordability of medicines in the country where less than 15 per cent of the population has health insurance.