Chinese researchers from the Wuhan Institute of Virology have applied for a national patent on an experimental drug developed by an American biotech firm that the scientists believe has the potential to fight the novel coronavirus, or 2019-nCoV.

The antiviral drug Remdesivir, developed by U.S. firm Gilead Sciences, was earlier approved by Chinese authorities for a clinical trial which began Thursday. A total of 761 coronavirus patients across several hospitals in Wuhan are enrolled for the first phase of trials, led by the China-Japan Friendship Hospital and the Institute of Materia Medica under the Chinese Academy of Medical Sciences (CAMS)

The clinical trial of the drug has been approved by the Ministry of Science and Technology (MOST), the National Health Commission and the National Medical Products Administration, Xinhua News Agency reported.

Remdesivir will be administered to 453 critical patients and 308 less severe patients, Cao Bin, head of the drug's clinical trial program said Wednesday at a press conference hosted by MOST at the Wuhan Jinyintan Hospital, which is also enrolled on the trial.

Remdesivir was developed by Gilead as a treatment for Ebola and Marburg virus infections, though the drug has subsequently showed reasonable antiviral activity against SARS and MERS coronavirus in previous cell and animal experiments.

While the experimental drug hasn't completed all clinical trials abroad and isn't licensed or approved anywhere in the world, the 2019-nCoV outbreak in China has made a compelling case for Remdesivir's human trials on coronavirus patients after it showed early signs of being highly effective.

"Its clinical trials against Ebola infections have been conducted abroad. In related domestic research, it has also shown fairly good antiviral activity against the 2019-nCoV at the cellular level," Cao asserted.

"Hopes have been pinned on the drug, but we have to wait for results of its actual effectiveness in the clinical trials," said Wang Chen, vice president of the Chinese Academy of Engineering and president of the CAMS.

Other potential drugs

Besides Remdesivir, researchers have also found some other drugs with seemingly positive results in the treatment of the 2019-nCoV. These included Chloroquine phosphate and Favipiravir, as well as some traditional Chinese medicines that contain active antiviral ingredients as drug candidates, for further animal experiments and clinical trials, the Global Times reported.

Earlier this week China's National Health Commission announced several medical institutions were studying the possibility of clinical trials for other potential antiviral drugs that could help in the fight against the 2019-nCoV pathogen.

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"Information and data of clinical trials for Lopinavir and Ritonavir and traditional Chinese medicines are being collected," NHC spokesperson Song Shuli was quoted as saying by Xinhua.

The NHC has issued a trial plan for the diagnosis and treatment of pneumonia caused by the novel coronavirus, Song said, adding that the plan offers detailed information of the medicines, both traditional Chinese medicines and Western medicines, used in the treatment of the disease.

Li Lanjuan, a top scientist from the Chinese Academy of Engineering, also announced on Tuesday that her team has verified two kinds of effective medicines against the 2019-nCoV named Arbidol and Darunavir.

'Patent application out of national interest'

Meanwhile, the Wuhan Institute of Virology under the Chinese Academy of Sciences claimed that their researchers have found two medicines – Remdesivir and Chloroquine – that "effectively inhibit the recently emerged novel coronavirus."

In a statement released on its website on Tuesday, the institute said it has applied for a patent in China for the use of Remdesivir in treating coronavirus patients. The application was made on January 21 jointly by the researchers from Wuhan Institute of Virology and the Academy of Military Medical Sciences, according to the statement.

Chloroquine, on the other hand, has been used to treat malaria since the 1940s. It has been sold on the Chinese market and can be independently provided, according to the institute.

The patent application triggered heated discussions on Chinese social media, with users expressing concerns over intellectual property rights, the Global Times reported. Some questioned the institute's eligibility to patent a medicine made by a U.S. company in China.

Gilead Sciences, in an email to the Global Times, however clarified that they have reached agreement with China's health authorities to carry out two clinical trials on patients infected with the coronavirus in order to make sure whether the drug is safe and effective in treating the virus.

In order to prevent, treat and control epidemic diseases, the Chinese National Intellectual Property Administration (CNIPA) can grant compulsory licenses in a national emergency and extraordinary situation to protect the public's interests, Chen Jihong, an expert in patent law at the Beijing Zhonglun Law Firm, told the Global Times.

If the Wuhan Institute's patent application is approved, Gilead would need to get the Chinese institute on board in sales of Remdesivir for treating 2019-nCoV patients outside China. But, the U.S. drug manufacturer will retain the global rights to market the medication, once approved, in treating Ebola and SARS for which the drug was originally developed.

The Wuhan Institute has urged foreign companies to withhold enforcing lawful patent rights to assist China's fight against the coronavirus epidemic. The institute said in its statement that it made the patent application out of national interest, and won't exercise its patent rights if foreign pharmaceutical firms cooperate with China to curb the epidemic.

While the American firm didn't make any statement on Wuhan Institute's patent application, Chinese experts and lawyers felt that the application is reasonable and in line with the Patent Law of China. Gilead only lays claims to Remdesivir's chemical compounds, while the Wuhan institute has applied for methods of use regarding the pharmaceutical product, some of them told the Global Times.

"The good thing in having a patent is that it would lead to cross-licensing situations that give China more bargaining chips in negotiating the licensing fee with Gilead," Wang Yanyu, a senior partner at AllBright Law Offices in Beijing, told the Bloomberg news agency.

Wang added that filing of the patent application by a stakeholder in China makes perfect sense. "Most of the patients are here, rather than in the U.S., which makes it unlikely that Gilead will do all these tests," he said.