COVID-19: Favipiravir shows hope in Mumbai trial

MUMBAI: While the WHO last week recommended that antiviral remdesivir not be used for severely ill Covid-19 patients, Mumbai doctors published the first scientific study showing another antiviral, favipiravir, reduced the "cure time" in mild cases.

"We found favipiravir improved the time to clinical cure by around three days," said the study's main author Dr Zarir F Udwadia. Patients who took the drug cleared the virus 30% (two days) faster than those on standard treatment. The study has been published in the peer-reviewed International Journal of Infectious Diseases.

"This may not sound like a very big difference, but is significant. There are so few treatment options that when a drug gives even a promising signal, it's exciting news," said Dr Udwadia.


Since the pandemic began almost a year back in Wuhan, China, various drugs have been tried out to control it. However, apart from steroids, none of the other drugs ranging from plasma to remdesivir to HCQS have been scientifically shown to help Covid-19 patients.

The current favipiravir trial was conducted from May 3 to July 3 among 150 patients admitted at Breach Candy Hospital; as it was a randomised trial, 75 patients were given favipiravir and another 'control group' received some other drugs. "The median time to cessation of viral shedding was five days versus seven days in the control group," said the study. The median time to clinical cure was three days in the 75 patients treated with favipiravir versus five days in the control group. The study concluded that favipiravir may be beneficial in mild-to-moderate Covid-19 cases.

"If the results from our study are validated by other larger studies currently underway in Boston and Stanford, favipiravir could have a role akin to Oseltamivir (another antiviral used to treat influenza such H1N1)," said Dr Udwadia. Dr Shashank Joshi, who is a member of the state government's task force on Covid-19, concurred that favipiravir is a "good" drug. "It is a good drug if used in the first 72 hours. One needs to hit hard and hit early," said Dr Joshi, who was not a part of the current study but had previously published a study on favipiravir.

The drug has been widely used in Japan, Russia and Thailand before Indian authorities approved its use for Covid-19 patients. It is widely prescribed in India for patients who prefer home isolation as it is an oral medicine (remdesivir, which is prescribed for severe Covid-19 patients is given in IV form and in hospitals only).

"The DCGI approved the use of this drug rather prematurely I thought, in the early days when the pandemic was raging in June. It was important for us to put this drug to the test by rapidly designing a good randomised, multicenter Phase 3 study which we implemented aided by the main manufacturer of this drug, Glenmark," said Dr Udwadia.

His study noted it caused a mild and transient rise in uric acid levels that was reversible. "It is a safe drug, except in pregnant or lactating women for whom it must never be used."