The Foster City-based pharmaceutical company Gilead Sciences, which specializes in antiviral drugs, recently donated some of its experimental drug remdesivir for use in studying potential treatments for the Wuhan coronavirus. But a legal fight is brewing after Gilead applied for a Chinese patent for the drug in 2016, and still has not received one, and a group of researchers in Wuhan just applied for their own patent for Gilead's drug last month.

As the coronavirus outbreak worsens in central China, doctors have yet to identify a drug treatment that is effective against the virus. Remdesivir, which was developed to treat Ebola, may be an effective treatment against the family of coronaviruses. It is currently being used in combination with an HIV drug, ritonavir, to treat a pair of Chinese nationals with the coronavirus at a hospital in Rome after they became ill in Italy, as the New York Times reports.

But now as more doctors want to try treating patients with the drug near ground zero of the outbreak in Wuhan, the government-run Wuhan Institute of Virology announced this week that it had applied for a "use patent" for remdesivir. Their patent specifies the use of the drug to treat the novel coronavirus, while Gilead's three-plus-year-old patent application only specified using remdesivir to treat the family of coronaviruses. The Chinese researchers' application was filed January 21.

As the Associated Press reports, this all comes back to the trade war with China, and the country's practice of "abus[ing] its regulatory system to pressure foreign companies to hand over valuable technology."

Ryan McKeel, a spokesperson for Gilead, tells the AP, "Gilead has no influence over whether a patent office issues a patent to the Chinese researchers. Their application has been filed more than three years after Gilead’s filing and will be considered in view of what is already known about the compound and pending patent applications."

For their part, the Chinese authorities have acknowledged that there may be "intellectual property barriers," but they said the patent application had been made in order to "protect national interests."

Per the AP, "China has the right under World Trade Organization rules to declare an emergency and compel a company to license a patent to protect the public. [But] It would be required to pay a license fee that is deemed fair market value." If the Chinese researchers' patent goes through, China might avoid paying that fee to Gilead.

Clinical trials involving remdesivir and other antiviral treatments — as well as some traditional Chinese remedies — are set to begin soon. Remdesivir has yet to be approved for treatment of anything, anywhere in the world. But Gilead said last week it would be cooperating with Chinese health authorities to study the use of the drug.

As of Thursday there were over 28,000 cases of coronavirus infection reported in mainland China, with 24 more in Hong Kong, and 158 elsewhere in Asia. The death toll from the virus now stands at 567, and that now includes the whistleblower doctor who was reprimanded by the Chinese government for spreading "rumors" about the new virus back in December. As the AP reports, 34-year-old ophthalmologist Dr. Li Wenliang himself succumbed to the virus this week at Wuhan Central Hospital. On the hospital's social media account, it said, "We deeply regret and mourn this."

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