Adagio Therapeutics (NSDQ:ADGI) saw its share price drop 82% to $6.85 in afternoon trading after releasing data reflecting a reduction in vitro neutralizing activity of ADG20 against the Omicron SARS-CoV-2 variant.
ADG20, the company’s lead product candidate, is a neutralizing monoclonal antibody intended to potentially treat and prevent COVID-19.
In vitro data from authentic and pseudovirus testing of the Omicron variant reflected a more than 300-fold reduction in neutralizing activity of the neutralizing antibody against Omicron.
The company is conducting further research.
“Due to the highly conserved and immunorecessive nature of the epitope recognized by ADG20, we anticipated that ADG20 would retain neutralizing activity against Omicron, consistent with activity observed in in vitro models with all other known variants of concern,” said Tillman Gerngross, CEO of Adagio, in a press release.
The latest data “show that the combination of mutations present in the Omicron spike protein led to a reduction in ADG20 neutralization that was not suggested by prior data,” Gerngross added.
Adagio developed ADG20 to offer broad protection against SARS-CoV-2 variants.
The company’s prior research indicated that it offers activity against various variants, including Alpha, Beta, Delta and Gamma.
ADG20 is the subject of two Phase 2/3 clinical studies.