Monoclonal antibodies appear safe as COVID-19 treatment during pregnancy
Pregnant patients who received monoclonal antibody treatments had no higher risk for adverse obstetric events but also no significant improvement on COVID-19-related outcomes, a retrospective study found.
Monoclonal antibody treatments for COVID-19 appear safe during pregnancy, a recent study found.
The retrospective study included 944 pregnant patients with positive SARS-CoV-2 tests (median age, 30 years; 79.5% White; median Charlson Comorbidity Index score, 0) and compared outcomes by whether the patients received bamlanivimab and etesevimab, casirivimab and imdevimab, or sotrovimab versus no monoclonal antibody treatment. Results were published by Annals of Internal Medicine on Nov. 15.
In total, 552 patients (58%) received an antibody treatment (69% sotrovimab). The median gestational age at COVID-19 diagnosis or treatment was 179 days, and of those with known vaccination status, 62% were fully vaccinated. Only eight drug-related adverse events (1.4%) were identified, and there were no differences in any obstetric-associated outcome by whether patients received monoclonal antibodies or not.
On the composite outcome of COVID-19-related hospital admission, ED visit, delivery, or mortality within 28 days, the treated patients had a trend toward reduced risk (risk ratio [RR], 0.71 [95% CI, 0.37 to 1.4]; propensity score-matched RR, 0.61 [95% CI, 0.34 to 1.1]). There were no deaths among antibody-treated patients and one among the patients who didn't receive antibodies. There were more non-COVID-19-related hospital admissions among antibody-group patients, but that difference disappeared with propensity-score matching.
“Importantly, mAb [monoclonal antibody] treatment seems safe in pregnancy with respect to drug-related adverse events and obstetric-associated outcomes,” said the study authors, who noted that pregnant patients without comorbidities who are infected with the omicron variant may not benefit from routine use of antibodies. “However, it is unknown whether mAbs would benefit (or harm) pregnant persons with additional risk factors for severe disease, and whether different mAbs are variably effective against different SARS-CoV-2 variants in pregnant persons,” they wrote.
The authors noted that they weren't able to explain the greater number of non-COVID-19-related hospitalizations among antibody-treated patients, but potential causes include that those patients were more likely to be vaccinated, receive fertility care, and have commercial insurance and may have been watched more closely due to their receipt of monoclonal antibodies. Limitations of the study include that adverse drug-related events may have gone unreported and that most of the data were on one monoclonal antibody treatment.