Will Covid-19 drugs be less effective against Omicron variant?

As the highly mutated Omicron coronavirus variant surfaces in more places around the world, there is concern that it will evade a class of drugs – known as monoclonal antibodies – that can help prevent a person from becoming very ill with Covid-19.

- Joyce Teo

These monoclonal antibodies – laboratory-made versions of the antibodies produced by the body to fight Covid-19 – are designed to look for the spike protein of the coronavirus.

Associate Professor Luo Dahai from Nanyang Technological University’s Lee Kong Chian School of Medicine said the mutations found in Omicron are mainly focused on the virus surface’s spike proteins, which may thus make the spike protein-targeting antibodies less effective.

At Alexandra Hospital, Dr Louisa Sun, an infectious diseases consultant, said the main concern where drugs are concerned is monoclonal antibodies, as most other Covid-19 treatments do not target the virus.

Still, doctors and public health experts are watching closely to see whether Omicron will affect vaccine effectiveness and cause more severe disease and deaths, she said.

Currently, the commonly used drugs for Covid-19 fall under three main categories – antibody treatments, anti-inflammatory drugs and antivirals.

ANTIBODY TREATMENTS

Antibody treatments can block the coronavirus from entering human cells and neutralise it. Monoclonal antibodies are given to patients early in the course of illness.

“These are injectable drugs and are costly as their production process is complex,” said Dr Sun.