After grappling with the coronavirus for more than a year, a number of oral drugs are being tested across world to treat  Covid-19 patients. Many of these formulations are  currently in mid stage clinical trials, and, if successful, could be ready by end of the year.

The list includes Molnupiravir, Baricitinib,  colchicine, Bamlanivimab (LY-CoV555), Chloroquine phosphate, Bemcentinib, Fingolimod,  metformin, Nafamostat,  Famotidine and Umifenovir combination, zuclopenthixol, Kevzara (sarilumab), and  nebivolol.

Pfizer is working on one oral drug to treat Covid-19 at the first sign of illness. It is expected by the end of the year. The drug is part of a class of medicines called protease inhibitors and works by inhibiting an enzyme that the virus needs to replicate in human cells.

Scientists from the National Institutes of Health (NIH) in the US and the University of Plymouth in the UK found that MK-4482, also called Molnupiravir, was effective when provided up to 12 hours before or 12 hours after infection with SARS-CoV-2, that causes Covid-19. This could be a potential oral drug to treat Covid-19. This is being developed by German company Merck with Ridgeback Biotherapeutics.

An antiviral drug called umifenovir (marketed in Russia under the brand name Arbidol, and also available in China for the treatment of influenza) is being studied in China and other countries as a treatment for Covid-19.

Two other oral agents are being developed by RedHill Biopharma --- one for severe Covid-19 infection for hospitalised patients, and the other one for patients at home with mild infection.

The first, opaganib (Yeliva), has proceeded to a phase 2/3 global trial for hospitalised patients. In phase 2, the drug was shown to be safe in patients requiring oxygen and effectively reduced the need for oxygen by the end of the treatment period.