A new study has shown that monoclonal antibody treatment (mAb), for COVID-19 is safe during pregnancy. However, it was not effective.
Retrospective, propensity-matched cohort study, published in Annals of Internal MedicineThe study included 944 pregnant women who were positive for SARS-CoV-2 infected during the period April 30, 2021 to January 21, 2022.
Investigators compared monoclonal antibody treatment using bamlanivimab, etesevimab. casirivimab, imdevimab, sotrovimab, or sotrovimab to no mAb treatment.
“Importantly, mAb treatment seems safe in pregnancy with respect to drug-related adverse events and obstetric-associated outcomes (that is, gestational age at delivery, birthweight, stillbirth, NICU admission, hypertension, severe maternal morbidity, and maternal ICU visit),” the study authors, led by Erin K. McCreary, PharmD, of the University of Pittsburgh School of Medicine, wrote.
The median age of the participants was 30 years old, and they were white at 79.5%. Median gestational period at COVID-19 diagnosis and treatment was 179. 69% received sotrovimab while 62% had been fully vaccinated.
Eight (1.4%) patients who received mAb were subject to mild drug-related adverse reactions. No severe reactions were reported from mAb injections. Between those who had received mAb treatment, and those who didn’t, the average gestational period at delivery was 273 days. The treatment group had an average birthweight of 3290 grams, while the untreated group had 3240. The treatment group had no deaths, while the untreated suffered one.
“In pregnant persons with mild to moderate COVID-19, adverse events after mAb treatment were mild and rare,” the study authors wrote. “There was no difference in obstetric-associated safety outcomes between mAb treatment and no treatment among persons who delievered.”
Study results showed no significant difference in COVID-19 outcomes among those who received mAb and those who did not, based on a composite number of hospitalizations, emergecy departments visits, or mortality at Day 28.
“In the total population, the risk ratio for mAb treatment of the composite 28-day COVID-19–associated outcome was 0.71 (95% CI, 0.37 to 1.4). The propensity score-matched risk ratio was 0.61 (95% CI, 0.34 to 1.1),” the authors noted.
According to the study authors, the rate of deaths and hospitalizations in the study group was lower than that of the general population. This could be due to the fact that they were younger, had fewer comorbidities, and had received high levels of vaccinations.
“The neutral finding from effectiveness models may be due to the sample size of the cohort or the absence of a true treatment effect,” the authors wrote.
The study couldn’t evaluate risk-adjusted outcomes for pregnant people with higher risk for COVID-19 complications such as comorbidities or unvaccinated status.
Patients in the treatment group had more patients (14, or 2.5%), who were admitted for non-COVID-19 related issues than those in the untreated (2, of 0.5%). However, there was no difference in the propensity matched cohort.
There were some limitations to the study, such as the possible underrepresentation drug-related adverse events. Both patients and the parovider reported this.
Yale University School of Medicine did a smaller study that found sotrovimab safe and well tolerated by pregnant women and newborns.