The COVID-19 antibody treatment from Regeneron Pharmaceuticals, as well as other similar medications, may be less effective against the new Omicron coronavirus type, the company warned on Tuesday.

More research is being done to confirm and quantify this potential impact using the real Omicron variant sequence, according to the pharmaceutical.

Before the bell, Regeneron shares were down 2.8% at $636.

Moderna chief executive officer said COVID-19 vaccines are unlikely to be as powerful against Omicron as they have been in the past, sending global markets lower on Tuesday.

Individual mutations found in Omicron, according to Regeneron, indicate "there may be diminished neutralizing activity of both vaccine-induced and monoclonal antibody imparted immunity."

According to Regeneron, the REGEN-COV COVID-19 antibody cocktail was used in the study.

Eli Lilly and Company and Vir Biotechnology, both of which have developed COVID-19 antibody medicines, did not immediately respond to a major Newswire request for comment.Fast-moving Regeneron eyes summer clinical trial for COVID-19 antibody cocktail therapy | FierceBiotech

According to the World Health Organization and scientists, determining whether Omicron is likely to cause serious illness or evade vaccine-induced immunity could take weeks.

Vaccine producers are already prepared for the possibility that their current vaccines would be ineffective against the new variety, with many companies declaring on Monday that they had begun developing Omicron-specific vaccines.