Sotrovimab of no help in attenuating COVID-19 severity in face of Omicron BA.2 subvariant

Treatment with sotrovimab does not appear to confer protection against severe forms of COVID-19 in a setting dominated by the Omicron BA.2 subvariant, a study has found.

The case-control study included a total of 3,364 patients in Qatar who had documented SARS-CoV-2 infection and who were eligible for sotrovimab treatment per US Food and Drug Administration (FDA) guidelines. Of these patients, 519 received the treatment while the remaining 2,845 served as controls.

After matching, a total of 345 patients were included in the treatment group and 583 in the untreated control group. The median age was 39 years, and patients were of diverse nationality backgrounds and predominantly vaccinated females. Most of them caught the infection during the Omicron wave.

Compared with no treatment, sotrovimab use did not lower the odds of progression to severe, critical, or fatal COVID-19 (adjusted odds ratio [aOR], 2.67, 95 percent confidence interval [CI], 0.60–11.91). The same was true in the subgroup of patients at higher risk of severe forms of COVID-19 (aOR, 0.65, 95 percent CI, 0.17–2.48).

The findings may be explained by the fact that most infections among the patients included in the study occurred during the Omicron wave and were predominantly due to BA.2, with previous evidence demonstrated lower neutralizing activity of sotrovimab against this particular Omicron subvariant, according to the researchers. [N Engl J Med 2022;386:1804-1816; N Engl J Med 2022;387:21-34; Nat Commun 2022;13:4675; N Engl J Med 2022;386:995-998]

Alternatively, the patients who consented and received the treatment may have perceived a need for this treatment because of poorer underlying health, thereby biasing effectiveness of the treatment, they added.

The US Food and Drug Administration has recently blocked the use of sotrovimab in regions where BA.2 is dominant. [https://www.fda.gov/media/149534/download]