TOPLINE: 

Among pregnant patients diagnosed with COVID-19, only 6.7% received ritonavir-boosted nirmatrelvir (NMV/r) treatment compared with 43% of those with influenza who received oseltamivir. The largest treatment gap occurred in clinician prescribing practices, with 89.3% of pregnant COVID-19 patients never being prescribed NMV/r despite clinical recommendations.

METHODOLOGY:

• Researchers conducted a retrospective cohort study of 9698 pregnancies with COVID-19 and 1514 pregnancies with influenza ending between December 22, 2021, and June 30, 2024, among patients aged 18-49 years within Kaiser Permanente Southern California.
• Outpatient COVID-19 and influenza diagnoses coded with International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) and antiviral prescribing and dispensing data were ascertained from the integrated electronic health record system.
• Patients were considered prescribed or dispensed a treatment if it occurred within 5 days of diagnosis, with treatment uptake referring to antivirals dispensed.
• Researchers calculated prescribing and dispensing rates and estimated adjusted prevalence ratios (aPRs) with 95% CI via Poisson regression models with robust standard errors.
• Analysis assessed variation in treatment uptake by patient and clinical characteristics including underlying medical conditions and clinical severity of presentation.

TAKEAWAY:

• Among pregnant women with COVID-19, 10.7% were prescribed NMV/r and 6.7% had a dispensing record, while among pregnant women with influenza, 54.1% were prescribed and 43% were dispensed oseltamivir.
• Among those prescribed NMV/r, 62.5% were dispensed compared with 78.5% for oseltamivir, indicating patient hesitancy may contribute to lower treatment uptake across both conditions.
• NMV/r treatment increased over time from 3.5% in 2022 to 19.4% in 2024 but remained well below oseltamivir treatment rates, which were consistently greater than 40% over the same period.
• Higher NMV/r treatment was associated with underlying medical conditions (two conditions vs none: aPR, 1.42; 95% CI, 1.16-1.75) but not oseltamivir (aPR, 1.00; 95% CI, 0.85-1.18), with NMV/r prescribing appearing disproportionately restricted to patients with more severe clinical presentations.

IN PRACTICE:

"NMV/r use in pregnancy is associated with reduced maternal morbidity and mortality. Given the large proportion of pregnant women who are unvaccinated and untreated for COVID-19, the risk of progression to severe disease remains high. Our findings underscore the need for targeted clinician education to support guideline-concordant prescribing," wrote the authors of the study.

SOURCE:

The study was led by Annette K. Regan, PhD, MPH, Kaiser Permanente Southern California in Pasadena. It was published online in the American Journal of Obstetrics and Gynecology.

LIMITATIONS: 

The study was conducted within a single integrated healthcare system in Southern California, which may limit the generalizability of findings to other healthcare settings or geographic regions with different patient populations and prescribing practices. The reliance on ICD-10-CM coded diagnoses from electronic health records may have resulted in misclassification of COVID-19 and influenza cases, potentially affecting the accuracy of treatment rate estimates. The study did not assess reasons for nonprescribing or patient refusal of prescribed medications, limiting understanding of the specific barriers to treatment uptake. The observational study design precludes determination of causal relationships between patient characteristics and treatment patterns.

DISCLOSURES:

Kaiser Community Benefit Funds provided support for this study. Regan disclosed receiving funding paid to her institution by Merck and membership on a Data Safety Monitoring Board for Moderna for work unrelated to the present study, with payments made to her institution. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.