• The European Medicines Agency (EMA) cautioned that monoclonal antibodies are unlikely to be effective against emerging strains.

Covid-19 antibody treatments are ineffective against the newest and increasingly dominant strains of the virus, the EU's drug watchdog warned on Friday.

While several monoclonal antibodies, given by injection or infusion in hospital, have contributed to blunt the worst of the disease for hospitalized patients, as they target the spike protein of the virus, the European Medicines Agency (EMA) "cautioned (they) are unlikely to be effective against emerging strains".  

Lab tests have shown that they "are poorly effective at neutralising Omicron strains BA.4.6, BA.2.75.2 and XBB," the Amsterdam-based regulator said in a statement, adding that they "do not significantly neutralise BQ.1 and BQ.1.1, which are expected to become the dominant strains in the EU in the coming weeks".  

The main antibody treatments include AstraZeneca's Evusheld, Roche's Ronapreve, and GSK and Vir's Xevudy.

Pfizer's Paxlovid is one of the antiviral treatments that are expected to remain effective; thus, EU states should stock up on them for high-risk patients, the EMA said. 

Monoclonal antibodies had been proven to reduce hospitalization and death risks by up to 80%, but with the mutation of the virus, they have lost their edge.  

In September, the World Health Organisation (WHO) advised against the use of Xevudy and Ronapreve as they had stopped being effective against the new variants.  

The coronavirus has kept evolving since it emerged at the end of 2019 to cause a global pandemic that is now waning.  

While previous variants ike Alpha and Delta gradually disappeared, Omicron and its subvariants have dominated throughout 2022 and look set to continue into 2023.