Chinese authorities have overturned Pfizer Inc.'s patent for Viagra in a widely watched case over how much China will do to protect the intellectual property rights of foreign companies.
Pfizer said Wednesday that it planned to appeal the decision, which is believed to be the first time the Chinese government has dismissed a pharmaceutical patent.
Pfizer spokesman Bryant Haskins said China's decision was "worrisome because we believe our patent is a strong one." He declined to disclose Viagra's sales in China, but said they were small.
Foreign drug companies have been watching the case as a test of China's commitment to intellectual property rights. Deputy U.S. Trade Representative Josette Shiner in November called the Pfizer Viagra patent challenge a "particularly troubling" example of China's commitment to intellectual property rights.
Patent protection for drugs has been afforded in China for only about a decade, said Joseph M. Damond, associate vice president for Japan and Asia Pacific at the Pharmaceutical Research and Manufacturers Assn., the industry's largest trade group.
Still, Damond said the Pfizer case should not be considered overly significant as China's patent system was still developing. He said the industry's main concern in China was the counterfeiting operations that festered throughout the country.
Viagra was introduced in China in 2000, and after six months, the official New China News Agency reported that 90% of Viagra pills sold in Shanghai, the country's largest city, were fake.
Pfizer has signed agreements with two government agencies in Shanghai to help local authorities spot counterfeit drugs and address the problem, Haskins said.
The patent reexamination board of China's State Intellectual Property Office overturned Pfizer's 2001 patent on the use of sildenafil citrate, Viagra's main ingredient. Phone calls to the office weren't answered Wednesday.
A group of Chinese drug makers had petitioned the office to nullify the patent, saying it failed to fulfill the "novelty requirement" of Chinese law.
Under that requirement, a patent can be granted only if no identical invention has been published or used within the country.