Real-world Effectiveness and Tolerability of Monoclonal Antibody Therapy for Ambulatory Patients With Early COVID-19
Open Forum Infectious Diseases, doi:10.1093/ofid/ofab331
Background. Neutralizing monoclonal antibodies (MAbs) are a promising therapy for early coronavirus disease 2019 , but their effectiveness has not been confirmed in a real-world setting. Methods. In this quasi-experimental pre-/postimplementation study, we estimated the effectiveness of MAb treatment within 7 days of symptom onset in high-risk ambulatory adults with COVID-19. The primary outcome was a composite of emergency department visits or hospitalizations within 14 days of positive test. Secondary outcomes included adverse events and 14-day mortality. The average treatment effect in the treated for MAb therapy was estimated using inverse probability of treatment weighting and the impact of MAb implementation using propensity-weighted interrupted time series analysis. Results. Pre-implementation (July-November 2020), 7404 qualifying patients were identified. Postimplementation (December 2020-January 2021), 594 patients received MAb treatment and 5536 did not. The primary outcome occurred in 75 (12.6%) MAb recipients, 1018 (18.4%) contemporaneous controls, and 1525 (20.6%) historical controls. MAb treatment was associated with decreased likelihood of emergency care or hospitalization (odds ratio, 0.69; 95% CI, 0.60-0.79). After implementation, the weighted probability that a given patient would require an emergency department visit or hospitalization decreased significantly (0.7% per day; 95% CI, 0.03%-0.10%). Mortality was 0.2% (n = 1) in the MAb group compared with 1.0% (n = 71) and 1.0% (n = 57) in pre-and postimplementation controls, respectively. Adverse events occurred in 7 (1.2%); 2 (0.3%) were considered serious. Conclusions. MAb treatment of high-risk ambulatory patients with early COVID-19 was well tolerated and likely effective at preventing the need for subsequent emergency department or hospital care.
Supplementary Data Supplementary materials are available at Open Forum Infectious Diseases online. Consisting of data provided by the authors to benefit the reader, the posted materials are not copyedited and are the sole responsibility of the authors, so questions or comments should be addressed to the corresponding author.
Austin, Stuart, Moving towards best practice when using inverse probability of treatment weighting (IPTW) using the propensity score to estimate causal treatment effects in observational studies, Stat Med
Cevik, Tate, Lloyd, SARS-CoV-2, SARS-CoV, and MERS-CoV viral load dynamics, duration of viral shedding, and infectiousness: a systematic review and meta-analysis, Lancet Microbe
Charlson, Pompei, Ales, Mackenzie, A new method of classifying prognostic comorbidity in longitudinal studies: development and validation, J Chronic Dis
Chatellier, Zapletal, Lemaitre, The number needed to treat: a clinically useful nomogram in its proper context, BMJ
Chen, Nirula, Heller, BLAZE-1 Investigators. SARS-CoV-2 neutralizing antibody LY-CoV555 in outpatients with Covid-19, N Engl J Med
Elixhauser, Steiner, Harris, Coffey, Comorbidity measures for use with administrative data, Med Care
Gottlieb, Nirula, Chen, Effect of bamlanivimab as monotherapy or in combination with etesevimab on viral load in patients with mild to moderate COVID-19: a randomized clinical trial, JAMA
Libster, Marc, Wappner, Fundación INFANT-COVID-19 Group. Early high-titer plasma therapy to prevent severe Covid-19 in older adults, N Engl J Med
Rubin, Estimating causal effects from large data sets using propensity scores, Ann Intern Med
Wagner, Soumerai, Zhang, Ross-Degnan, Segmented regression analysis of interrupted time series studies in medication use research, J Clin Pharm Ther
Webb, Levin, Grisel, Simple scoring tool to estimate risk of hospitalization and mortality in ambulatory and emergency department patients with COVID-19, MedRxiv, doi:10.1101/2021.02.22.21252171
Weinreich, Sivapalasingam, Norton, Trial Investigators. REGN-COV2, a neutralizing antibody cocktail, in outpatients with Covid-19, N Engl J Med