GILD Gilead Sciences Inc

BEIJING--Clinical trials being conducted in Wuhan to test Gilead Sciences Inc.'s antiviral drug, a promising remedy for the new coronavirus, are going more slowly than hoped for as the drugmaker struggles to recruit qualified patients, underscoring the challenges in quickly developing drugs during outbreaks.

The trials, aimed at testing more than 700 patients infected with the Wuhan coronavirus, have succeeded in recruiting fewer than 200 people after 10 days.

A total of 168 patients with severe symptoms, and 17 patients with mild and moderate symptoms, were recruited at 11 medical institutes across Wuhan, Zhang Xinmin, an official from China's Ministry of Science and Technology, said at a Saturday press conference.

The trials were first announced on Feb. 5 at Wuhan's Jinyintan Hospital, one of the main facilities treating coronavirus patients in the city at the epicenter of the outbreak. According to state-run Xinhua News Agency, the plan for the trials is to recruit 761 patients infected with the virus. They are to include 308 patients with mild and moderate symptoms and 452 with severe conditions.

Severely ill patients had to be within 12 days of the illness's onset and couldn't have taken other treatments within the past 30 days to qualify, according to the screening criteria. Mild and moderate patients who want to join trials needed to be within eight days of the illness's onset. All candidates had to have positive lab results for the infection.

These criteria have practically ruled out most candidates, since many patients in Wuhan have started taking medication at home--either those recommended by state media or based on anecdotes they read online while waiting to be admitted to hospitals.

Other patients with apparent symptoms, meanwhile, have received negative results in potentially flawed laboratory tests.

According to video footage from Xinhua, Gilead's drug, known as remdesivir, was first administered intravenously on Feb. 6 to a 68-year-old man who had developed severe symptoms and was treated at Jinyintan Hospital. It is unclear whether the patient was given the drug as part of a trial or for emergency use.

Zhao Jianping, a doctor at Wuhan Tongji Hospital who is heading a team advising on the treatment of coronavirus patients, said in a Feb. 7 press conference that two-thirds of the severe patients in the trials would be given the drug while the other third would be given a placebo. Those in the placebo group would also receive the standard treatment, Dr. Zhao said.

A Gilead spokeswoman said the two studies, for severe and more moderate cases, were initiated about a week apart and are being conducted by Chinese officials, not Gilead. "Any questions about the status of those studies would be best addressed by the principal investigator," she said.

Beijing pulmonologist Dr. Cao Bin, a prominent researcher deployed to Wuhan to help lead the medical care of patients as well as the two clinical trials, didn't respond to requests for comments.

Other than remedesivir, the antimalarial drug chloroquine and the influenza drug favipiravir have also shown some efficacy in clinical trials, Mr. Zhang of the Ministry of Science and Technology said Saturday.

Sun Yanrong, another official at the ministry, said separately on Monday that, based on preliminary clinical trials results, it appeared chloroquine was effective in treating the new coronavirus, with no severe side effects.

Experts have suggested including chloroquine, a drug that has been in clinical use for over 70 years, in the next national guidelines for treating the coronavirus, Ms. Sun added.

State-owned pharmaceutical giants China Resources Pharmaceutical Group Ltd. and China Medicine Health Industry Co. are ramping up productions of chloroquine, Zhao Shitang, an official with the state-owned Assets Supervision and Administration Commission said today.

Favipiravir has shown better efficacy with fewer side effects in a controlled study against Kaletra, an antiretroviral for HIV made by U.S. pharmaceutical giant AbbVie Inc., Shenzhen No. 3 Hospital in southern China said last week in a statement on its website recommending broader clinical use of the drug. The study was based on 80 patients infected with the new coronavirus, the statement said.

China's drug authorities last week approved favipiravir, a drug developed in Japan to treat influenza and which has also shown signs of efficacy against the Ebola virus, as a second-line treatment for influenza.

Favipiravir was also approved to be used in clinical trials of the new coronavirus, government data shows.

Zhejiang Hisun Pharmaceutical had an exclusive licensing agreement with Fujifilm Holdings Co. in 2016, but the patent expired last year, Zhejiang Hisun said in a company filing Monday. Hisun started production of the drug on Sunday.

Fanfan Wang

(END) Dow Jones Newswires

February 18, 2020 00:41 ET (05:41 GMT)

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