With the outbreak spreading fast and no vaccine or treatment on the horizon, Kato hoped to find an existing drug that could be used to treat the wave of patients that was sure to come. One candidate was an anti-influenza drug called Avigan, which had been developed decades earlier by the Fujifilm subsidiary Toyama Chemical.
In the weeks that followed, the Fujifilm team managed more than some governments could claim to have done in response to the spread of Covid-19: Working from different offices and factories, members of the group made contingency plans for ramping up production of the drug, advised clinical researchers throughout Japan, and helped get the drug to hospitals where its use had been approved by the government as an emergency measure to treat dozens of Covid-19 patients. On March 28—last Saturday—Prime Minister Shinzo Abe told reporters that his government had begun the formal process for designating Avigan as Japan’s standard treatment for Covid-19.
A critical step in that process involves clinical trials, one of which will conclude at the end of June. And while there is not yet any detailed data supporting Avigan’s effectiveness as a Covid-19 treatment, there are some reasons for optimism. One of them arrived on March 17, when Zhang Xinmin, an official at China’s Ministry of Science and Technology, said that favipiravir, the generic version of Avigan, had proved to be effective in treating Covid-19 patients at hospitals in Wuhan and Shenzhen.
It was, Zhang said, “very safe and clearly effective” for treating Covid-19 patients. And while the data and methodology behind Zhang’s claims have not been made public, he did announce some of the conclusions doctors had drawn from them: At a hospital in Shenzhen, Zhang claimed Covid-19 patients treated with favipiravir tested negative for the virus after a median of four days, rather than the 11 days it took for members of the study’s control group to test negative; in another study carried out in Wuhan, patients taking the drug allegedly recovered from fever nearly two days earlier than those who did not take the medication.
Such results, preliminary and unconfirmed as they are, would seem to conform with the way favipiravir works. Unlike most other influenza treatments, which inhibit the spread of the virus across cells by blocking the enzyme neuraminidase, favipiravir works by inhibiting the replication of viral genes within infected cells, thereby mitigating the virus’s ability to spread from one cell to another.
What this means, in practical terms, is that patients who take the drug while their viral load is low or moderate may prevent it from making them any sicker. And there is some evidence that favipiravir can achieve these same effects in viruses other than influenza. Prime Minister Abe seems to be among the believers, and on March 28 he announced that Japan will “start to boost production and proceed with clinical research in cooperation with those countries that wish to join us.” He also said that many countries had already expressed an interest in the drug.
Though Abe did not mention any of those countries by name, one of them seems to be the United States. According to a recent report in Politico, Fujifilm has discussed with the FDA and the US Department of Health and Human Services the possibility of Avigan trials in the US, and it is seeking research funding from the US government. After Abe spoke to President Trump by phone about Avigan, the report says, the White House National Security Council began pressuring the government to accept a donation of Avigan from Japan and asking the FDA to authorize its use on an emergency basis.
IN LATE 2014, favipiravir was deployed as an emergency treatment in West Africa, where an Ebola outbreak of unprecedented duration and scale was killing thousands of people. With the support of the World Health Organization, Doctors Without Borders offered the drug to a broad swath of infected patients on a compassionate use basis, provided that they were not pregnant, since favipiravir can cause serious birth defects.
A study concerning its use in Guinea showed promising, though not definitive, results: When administered to patients with low to moderate viral loads, favipiravir cut Ebola’s mortality rate in half, from 30 percent to 15 percent. Now, five years on, Japan’s government hopes it will have similar benefits against Covid-19, which as of April 3 had killed 61 of the 2,617 people who tested positive for the virus in the country.
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Fujifilm has refused to comment on China’s claims about favipiravir—it was not involved in the clinical trials carried out in China, which relied on drugs produced by its former manufacturing partner, Zhejiang Hisun Pharmaceutical, which has been China’s main producer of favipiravir since Fujifilm’s patent on the drug expired there last year.
The company received government approval to manufacture the drug for new and recurring influenza in mid-February, as well as approval for starting clinical trials to determine its efficacy against Covid-19. By late March, once trials had concluded, China had begun exporting favipiravir. In Turkey, health minister Fahrettin Koca said a shipment of the “special drug” from China was being used to treat Covid-19 patients in 40 different cities.
Japan, too, seems to have recognized Avigan’s utility as a tool of soft power. Three days after Zhang announced that the drug had been effective in clinical trials in China, Indonesian president Joko Widodo told reporters he’d imported 5,000 doses of Avigan, and that he was “in the process of ordering 2 million more.” This highlights the tension between hope and science in the battle to save lives from Covid-19—while not yet officially Japan’s go-to treatment for the novel coronavirus, Avigan has been successfully used to treat dozens of Japanese patients, according to Prime Minister Abe.
And while Japan’s government is waiting on the results of its own clinical trials before deploying the drug on a mass scale domestically, it seems willing enough to let countries like Indonesia roll the dice on it.
Indonesia is not the only country that would be trying its luck—Fujifilm told me a number of other countries have made inquiries or requests for Avigan, but the company declined to name them and won’t say how much of the drug it will be exporting.