Zydus Cadila’s antiviral drug for moderate COVID-19 disease gets emergency use approval

India’s drug regulator has granted an emergency use approval to Zydus Cadila’s antiviral drug ‘Virafin’ to treat moderate COVID-19 disease. In the phase-3 trial, there was a higher proportion of patients administered the drug becoming RT-PCR negative by day seven due to faster viral clearance.

The Indian drug regulator on April 23 granted an emergency use approval to Zydus Cadila’s antiviral drug ‘Virafin’, a pegylated interferon alpha-2b (PegIFN), to treat moderate COVID-19 disease in adults, says a company press release.

“A single dose subcutaneous regimen of the antiviral Virafin will make the treatment more convenient for the patients. When administered early on during COVID, Virafin will help patients recover faster and avoid much of the complications. Virafin will be available on the prescription of a medical specialist for use in hospital/institutional setup,” the release added.

The drug’s safety profile is already well known as it is used in treating people with chronic hepatitis B and C. The drug has been repurposed for treating moderate COVID-19 disease.

According to Dr. Sharvil Patel, Managing Director, Cadila Healthcare Limited the therapy “significantly reduces viral load when given early on and can help in better disease management”.

A multicentric trial carried out in 20-25 centres across India, the company found the drug reduced the need for supplemental oxygen. This clearly “indicates that the antiviral was able to control respiratory distress and failure which has been one of the major challenges in treating COVID-19”.

In the phase-3 trial, the drug was able to achieve “better clinical improvement in the patients suffering from COVID-19”. A “higher proportion of patients administered the drug were RT-PCR negative by day seven as it ensures faster viral clearance”. According to an April 5 company press release, the drug reduced the duration for supplemental oxygen to 56 hours from 84 hours in moderate COVID-19 patients.

Phase-2 trial results

The results of the phase-2 trial using the drug published in the International Journal of Infectious Diseases found that of the 20 participants who received the drug and standard of care 19 (95%) achieved clinical improvement on day 15 compared to 13 of the 20 (68.42%) participants who were in the control arm and received only standard of care. The trial found that 80% and 95% of participants who received the therapy plus standard of care were RT-PCR negative on day seven and 14, respectively, compared to 63% and 68% in the control arm.

The significant improvement in clinical status on day 15 is likely due to faster viral reduction compared to the control arm. Participants with moderate disease showed a difference as early as day seven, which became significant by day 14, the authors say in the paper.

Mild adverse events were reported in 11 participants in the phase-2 trial compared with eight in the control arm.

According to the release, type I interferons are the body’s first line of defence against many viral infections. In old people, the ability to produce interferon alpha in response to viral infections gets reduced, which might be the reason for higher mortality. The drug when administered early during the disease can replace this deficiency and help in the recovery process.

Published in The Hindu on April 23, 2021