Japan sending fujifilm's flu drug favipiravir to over 40 countries for covid-19 trials

3D illustration of coronavirus on a colored background. Leonello Calvetti | Stocktrek Images | Getty Images Since the world might wait years for a coronavirus vaccine, drugs that can

mitigate its effects are now in the spotlight. The U.S. Food and Drug Administration has approved Gilead Sciences' antiviral drug remdesivir as an emergency treatment for Covid-19, the

disease caused by the new coronavirus. While remdesivir is intended for the most severe cases, reducing recovery time, U.S. doctors are also testing an influenza drug made by a Japanese

photography company amid hopes that it may help a wider range of patients. U.S. TRIAL UNDER WAY Favipiravir works by preventing the virus from replicating in cells. It's marketed under

the brand Avigan and was developed in 2014 by Fujifilm Toyama Chemical, a unit of Fujifilm Holdings. As he extended the nationwide state of emergency until May 31, Japanese Prime Minister

Shinzo Abe said Monday he wants favipiravir approved for Covid-19 in May, as Japan moves to fast-track approval for remdesivir as well. In April the government said it will triple the

country's stockpile to enough doses for 2 million people. Fujifilm Toyama Chemical is working to increase its monthly production by July to 100,000 treatment courses, defined as doses

for a 14-day period, and 300,000 courses by September. The price of the drug has not been set in Japan, where the government decides medicine prices. Japan is expected to ship the drug to 43

countries for clinical studies on its effectiveness against Covid-19. The shipment is being sent through the United Nations Office for Project Services, and each country will receive enough

to treat between 20 and 100 people, Japan Foreign Minister Toshimitsu Motegi said last week. Fujifilm began a phase 2 clinical trial in Massachusetts in April. The trial called for about 50

patients and is taking place in collaboration with Brigham and Women's Hospital, Massachusetts General Hospital and the University of Massachusetts Medical School. Avigan influenza

tablets, produced by Fujifilm Holdings Corp., are arranged for a photograph at the company's headquarters in Tokyo, Japan. Akio Kon | Bloomberg | Getty Images "We expect the drug

will enhance clearance of virus and shorten the duration of Covid-19 illness," says Robert Finberg, chair of the school's Department of Medicine. "Previous studies with this

drug have indicated that it enhances clearance of influenza. We expect results in approximately one to two months." EARLY BOOST IN CHINA Health centers in China and Japan have been

studying favipiravir as a Covid-19 treatment for months. It also has been tested in Italy, and a trial is set to begin in India. In one clinical trial in China, patients taking the drug

tested negative for coronavirus after a median of four days, less than half the 11 days it took for patients in a control group, the China National Center for Biotechnology Development said

in March. It also found that 8.2% of favipiravir patients needed respiratory aid compared to 17.1% of the patients in the control group. Center director Zhang Xinmin called the drug

"very safe and clearly effective" and without obvious side effects, Nikkei news reported.   Japan approved favipiravir in 2014, but not for seasonal flu. It was given the OK for

novel or reemerging influenza viruses when other antiviral drugs don't work, and the government has to approve each case. There were no such cases in the past six years, but favipiravir

was studied in a Japanese trial for ixodid tick-borne infectious disease and serious fever with thrombocytopenia syndrome. The government of Guinea also approved the drug as a standard

treatment for patients with Ebola Virus Disease following a clinical trial in the West African country. "Avigan is a viral RNA polymerase inhibitor, with a new mechanism of action that

inhibits viral gene replication within infected cells," says Kana Matsumoto, a spokesperson for Fujifilm. "Due to this characteristic, the drug may potentially have an antiviral

effect on the viruses classified into the same type (single-stranded RNA virus) as influenza virus." Japanese researchers began administering favipiravir to Covid-19 patients around the

end of February. Fujifilm itself began a phase 3 clinical trial in Japan in March with about 100 patients, targeting those with mild and moderate symptoms. But it's not the only

effort. More than 2,000 people in Japan had been treated with favipiravir as part of clinical trials as of April 26, according to the Ministry of Health, Labor and Welfare. An official at

Fujita Health University Hospital in Aichi Prefecture, where a trial is under way, said staff would finish analyzing test data by the end of August. > We expect the drug will enhance 

clearance of virus and shorten the > duration of Covid-19 illness. >  > Robert Finberg > University of Massachusetts Medical School "I'm not sure what effect Avigan

had, but it gave me an added feeling of security," says a 42-year-old Tokyo resident with Covid-19 who didn't want his name used. He was hospitalized with mild symptoms in April

and was given favipiravir for about a week. After testing positive multiple times, he finally got a negative result on Monday and was discharged. SOURCES OF CONCERN There have been concerns

about favipiravir, however, due to reports of potential fetal deaths and deformities, as well as transmission via semen. In a review article published earlier this year in the journal

_Pharmacology & Therapeutics_, Japanese researchers concluded that "Favipiravir is expected to be an important therapeutic agent for severe influenza, the next pandemic influenza

strain, and other severe RNA virus infections for which standard treatments are not available." While noting an apparent lack of drug resistance with favipiravir, the authors said it

should not be given to pregnant women due to its negative effects on animal embryos. One expert in the U.S. also signaled caution, stressing that coronaviruses constitute a very different

family of viruses than the orthomyxovirus family, which includes influenza viruses. "While they both encode an RNA-dependent RNA polymerase, coronaviruses have a proofreading enzyme

that can remove nucleoside analog drugs that can induce mutations and block replication in influenza, so these drugs may not work well in coronaviruses," says Rachel Roper, associate

professor of microbiology and immunology at East Carolina University. "We can try it in clinical trials, but we must remember if there is no control group for comparison, there is no

data. Anecdotes do not make data, only well-designed and controlled studies can provide real data on drug efficacy." Still, doctors in the U.S. and Japan are hoping their studies will

help patients until people can be inoculated. "We will need drugs to treat acute disease as it occurs, and in the long-term a vaccine is the best option," Finberg says.