Second Batch of Experimental Gilead Coronavirus Drug Arrives in Wuhan

A second batch of Gilead Sciences Inc.’s experimental antiviral drug remdesivir has arrived in Wuhan, where it will be tested on patients infected with the Covid-19 coronavirus that has killed more than 1,500 people.

The drug was transported from the U.S. to China by FedEx to be distributed to hospitals in Wuhan, the epicenter of the virus, for two ongoing clinical trials on a combined 760 patients.

It is not known how many doses of the drug were shipped, but they follow some 3,400 doses of the drug and 900 placebo doses that reached Wuhan’s Jinyintan hospital last week as part of Phase 3 trials, which began on Feb. 6.

The trials are randomized, controlled and double-blinded, meaning neither doctors nor their patients know whether they are using the active drug or a placebo, so researchers can determine whether patients truly benefited from the new treatment or recovered on their own.

Patients and doctors will, however, be told if they suffer a serious adverse reaction. Remdesivir has not been approved anywhere in the world to treat any condition. But it has been tested on a small number of people, so its impact on the human body is not completely unknown.

Gilead’s drug has performed well in laboratory trials against other types of coronavirus including SARS and MERS, according to Australian infectious disease researcher and antiviral drug specialist Tony Cunningham. It has also been found to be effective at killing the virus which causes Covid-19 in the lab.

But evidence of its effectiveness in humans remains slim, Cunningham said, and a U.S. patient diagnosed with Covid-19 who was treated with it and recovered had already shown signs of improvement before it was administered, illustrating the need for well-designed clinical trials with control cases, even if it means some people in the trial will go without the drug.

The two Chinese trials of remdesivir have been registered on the U.S. trial registry ClinicalTrials.gov, with the records showing one is for severe cases of Covid-19 and one for mild and moderate cases.

Cao Bin of Beijing's China-Japan Friendship Hospital is leading the trials. According to the trial records, the first, on 452 patients with severe Covid-19 who have had the disease for at least 12 days, is expected to conclude on May 1. The second, on 308 patients with mild to moderate Covid-19, is expected to conclude on April 27.

Participants in both trials are required not to be involved in studies of any other experimental drugs for at least 28 days, and they must also agree to be “randomized,” meaning they will not know whether they are receiving the drug or a placebo.

Each participant will be given 200 mg of either remdesivir or the placebo on the first day of treatment, and 100 mg each day after that via an intravenous drip for nine days, the records say.

At least 40 clinical trials related to Covid-19 are ongoing in China, but the remdesivir trials are the only Phase 3 trials so far approved by Chinese authorities. Each prospective treatment will need to prove its effectiveness and safety before authorities make any decision on whether to approve its general use.

The remdesivir trials are backed by Capital Medical University in collaboration with the Chinese Academy of Medical Sciences.

Contact reporter Lu Yutong (yutonglu@caixin.com) and editor Flynn Murphy (flynnmurphy@caixin.com)