China Grants Three Patents to Gilead’s Remdesivir as Hopes Rise for Effective Treatment

(Caixin) Gilead Sciences Inc. has been granted three patents in China for its antiviral drug remdesivir, the most promising drug to treat the coronavirus that has infected more than 80,000 globally and killed nearly 2,800.

This development could mean a competing patent application by a Chinese state-backed research body for the same drug may not get approved.

The U.S. drugmaker has applied for eight patents for the drug in China, and five are still being reviewed, He Zhimin, deputy director of the National Intellectual Property Administration, said at a press conference Monday. The eight patents cover intellectual property including drug compounds, manufacturing methods, and drug usage.

Originally developed to treat the Ebola virus, remdesivir is now undergoing clinical tests for coronavirus treatment. An official from the World Health Organization (WHO) said the drug is showing signs that it may be able to help treat the coronavirus.

“There is only one drug right now that we think may have real efficacy and that’s remdesivir,” WHO assistant director-general Bruce Aylward said at a press conference in Beijing. The drug’s clinical trial results could be available within weeks, he said.

Chinese authorities are very focused on establishing the efficacy and safety of remdesivir, and hope a batch of effective drugs will be available as soon as possible, including remdesivir, he said.

Gilead filed a patent application in China as early as 2011 for “a method and compound for treating paramyxoviridae virus infection” and obtained approval in 2015, according to data from the National Intellectual Property Administration. The compound in the patent is remdesivir.

The U.S. company also filed patent applications in 2016 for use of remdesivir to treat coronavirus and other viruses. These patents haven’t been approved. But Gilead’s applications explicitly covered the use of remdesivir to inhibit the polymerase enzyme in coronavirus. This means Gilead claimed the use of remdesivir to treat coronavirus years before Wuhan Institute for Virology filed a similar patent application earlier this year.

Wuhan Institute of Virology, based in the Chinese city at the center of the epidemic, applied for a patent in China for use of remdesivir in treating the ailment on January 21, together with a military academy, according to a Feb. 4 statement on the institute’s website.

The move by the Wuhan research institute led to a dispute over intellectual property and drew criticism. The Wuhan institute subsequently said it made the patent application in the national interest and won’t exercise its patent rights if foreign pharmaceutical companies work with China to curb the contagion, the institute said in the statement.

“They shouldn’t have done that,” because they don’t own the compound structure or clinical data, said Sun Zhongshi, an expert from the Drug Evaluation Center of China’s State Food and Drug Administration.

Gilead Sciences is one of many firms seeking an effective treatment for the coronavirus. Global pharmaceutical giants Johnson & Johnson, GlaxoSmithKline, and dozens of domestic drugmakers are also working on vaccines and treatments.

More than 200 clinical trials of different treatments are ongoing. Experts worry that so many trials could pose a burden to front-line medical care.

Each clinical trial needs nearly 1,000 patients with mild symptoms to prove a 5-percentage point improvement in the cure rate, or at least 800 patients with severe conditions, according to a paper authored by health statistics and epidemiology experts in the Chinese Journal of Epidemiology.

In some clinical trials, the sample size is obviously insufficient to reach a reliable conclusion, the paper said. Some trials have only a few samples. As fewer new cases have been confirmed in China in recent days, 15 provinces have fewer than 50 confirmed cases, which means there are not enough patients to conduct such trials.

WHO’s Aylward said at Monday’s press conference that he talked with a Chinese researcher in Wuhan, who told him the biggest challenge now in developing antiviral drugs is difficulty in recruiting subjects because the number of patients is declining.

The WHO official called for prioritizing research projects that can help to save lives most rapidly.

Source: Caixin By Yu Dawei and Denise Jia