Anti-SARS-CoV-2 antibodies suggested to be safe to use in pregnancy

By Dr. Sanchari Sinha Dutta, Ph.D.Reviewed by Aimee MolineuxNov 30 2021

A recent Mayo Clinic study conducted on pregnant women with mild to moderate coronavirus disease 2019 (COVID-19) has suggested that therapeutic monoclonal antibodies targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike proteins are effective and safe for both mothers and infants.

Study: Outcomes of Anti-Spike Monoclonal Antibody Therapy in Pregnant Women with Mild to Moderate COVID-19. Image Credit: Natalia Deriabina/Shutterstock

The study is currently available on the medRxiv* preprint server, while the article undergoes peer review.

This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources

Background

It has been documented in the literature that pregnant women with COVID-19 are at higher risk of developing serious complications that require hospitalization. The risk is comparatively higher for those aged over 35 years or who have preexisting health conditions including diabetes, obesity, or hypertension.

In the US, the Food and Drug Administration (FDA) has granted emergency use approval for therapeutic anti-spike monoclonal antibodies for treating mild to moderate COVID-19 patients who are at higher risk of developing serious complications. In this context, several clinical trials have indicated that these antibodies are effective in reducing viral load, disease severity, and requirement for hospitalization in the at-risk population.

In the current study, the scientists have evaluated the safety and efficacy profiles of anti-spike IgG monoclonal antibodies in pregnant women who have mild to moderate COVID-19.

Study design

The study was conducted on a total of 51 pregnant women who had received monoclonal antibody therapy during pregnancy. Of them, four received bamlanivimab monotherapy, three received the bamlanivimab-etesevimab combination, and 44 received the casirivimab-imdevimab combination.  

For the analysis, the scientists collected patient data from the Mayo Clinic database. They specifically focused on the patient’s age, SARS-CoV-2 detection and symptom onset dates, gestational age at COVID-19 diagnosis, type of antibody therapy administered, and COVID-19 related complications and hospitalization.

Important observations

The average gestational age of patients during antibody therapy infusion was 180 days. Specifically, four patients received the therapy during the first trimester, 17 during the second trimester, and 30 during the third trimester. The most reported comorbidities of patients were depression, migraine, obesity, asthma, anxiety, and diabetes.

Regarding disease severity, all enrolled patients were diagnosed with mild to moderate COVID-19. The average duration between disease diagnosis and therapy administration was 2.9 days.

Safety and efficacy of monoclonal antibody therapy

None of the patients experienced any adverse reactions during and after one hour of anti-spike monoclonal antibody therapy administration. Moreover, none of them required any other treatments besides antibody therapy.

Of 51 enrolled patients, ten required medical assistance in the emergency department after antibody infusion. However, among various reasons of emergency department visit, only one was related to COVID-19, i.e., dyspnea. Other reasons were pregnancy-related nausea and vomiting, asthma, cough, and post-operative pain, which occurred at least 30 days after antibody infusion.

Overall, four patients required hospitalization for reasons not related to antibody infusion. Specifically, one patient was hospitalized after 42 days of infusion because of a headache that required sphenopalatine ganglion blockade. The other three patients were hospitalized for observation after an ischemic attack, for a flair of Crohn’s disease, and for an intrauterine fetal death due to Ebstein anomaly (a congenital heart defect), respectively. All hospitalization events occurred several days after antibody infusion.

As analyzed and reported by a team of specialists, the intrauterine fetal death was not related to antibody infusion. It might be due to vertical maternal–fetal transmission of SARS-CoV-2.

None of the patients developed pregnancy-related complications during the follow-up period, and no event of fetal distress occurred following antibody infusion. During the study period, 29 out of 51 antibody-treated patients delivered healthy babies and 21 were still pregnant without any complication.

Study significance

The study findings suggest that anti-spike monoclonal antibody therapy is safe and effective in preventing COVID-19 severity and hospitalization in at-risk pregnant women who have mild to moderate COVID-19.

As mentioned by the scientists, despite the risk of crossing the placenta, monoclonal antibodies used in the study are safe as they are specifically targeting the viral spike protein and not human antigens. Given the observed benefits, they have highlighted the need for future studies with a large sample size to effectively conclude the therapeutic benefits of monoclonal antibodies during pregnancy.

This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources