Effectiveness of Monoclonal Antibodies in Preventing Severe COVID-19 With Emergence of the Delta Variant.

Anti-spike monoclonal antibodies have proven invaluable in preventing severe outcomes from COVID-19, including hospitalization and death. The rise of the SARS-CoV-2 delta variant begs the question of whether monoclonal antibodies maintain similar efficacy now as they had when the alpha and beta variants predominated, when they were first assessed and approved. We used a retrospective cohort to compare rates of severe outcomes in an epoch in which alpha and beta were predominant compared with delta. A total of 5356 patients were infused during the alpha/beta variant-predominant (n=4874) and delta variant-predominant (n=482) era. Overall, odds of severe infection were 3.0% of patients in the alpha/beta-predominant era compared with 4.9% in the delta-predominant cohort. The unadjusted odds ratio (OR) was higher for severe disease in the delta era (OR, 1.67; 95% CI, 0.96 to 2.89), particularly when adjusted for Charlson Comorbidity Index (adjusted OR, 2.04; 95% CI, 1.30 to 3.08). The higher odds of severe infection could be due to a more virulent delta variant, although the possibility of decreased anti-spike monoclonal antibody effectiveness in the clinical setting cannot be excluded. Research into the most effective strategies for using and improving anti-spike monoclonals for the treatment of emerging variants is warranted.

Monoclonal Antibody Treatment of Breakthrough COVID-19 in Fully Vaccinated Individuals with High-Risk Comorbidities.

BACKGROUND: Breakthrough coronavirus disease 2019 (COVID-19) may occur in fully vaccinated persons. METHODS: We assessed the clinical outcomes of breakthrough COVID-19 in fully vaccinated individuals. RESULTS: In this cohort of 1395 persons (mean age, 54.3 years; 60% female; median body mass index, 30.7) who developed breakthrough COVID- 19, there were 107 (7.7%) who required hospitalization by day 28. Hospitalization was significantly associated with the number of medical comorbidities. Antispike monoclonal antibody treatment was significantly associated with a lower risk of hospitalization (odds ratio, 0.227; 95% confidence interval, 0.128-0.403; P < .001). The number needed to treat (NNT) to prevent 1 hospitalization was 225 among the lowest risk patient group compared with NNT of 4 among those with highest numbers of medical comorbidity. CONCLUSIONS: Monoclonal antibody treatment is associated with reduced hospitalization in vaccinated high-risk persons with mild to moderate COVID-19.

Casirivimab-Imdevimab treatment is associated with reduced rates of hospitalization among high-risk patients with mild to moderate coronavirus disease-19.

BACKGROUND: Real-world clinical data to support the use of casirivimab-imdevimab for the treatment of outpatients with mild to moderate coronavirus disease-19 (COVID-19) is needed. This study aimed to assess the outcomes of casirivimab-imdevimab treatment of mild to moderate COVID-19. METHODS: A retrospective cohort of 696 patients who received casirivimab-imdevimab between December 4, 2020 and April 9, 2021 was compared to a propensity-matched control of 696 untreated patients with mild to moderate COVID-19 at Mayo Clinic sites in Arizona, Florida, Minnesota, and Wisconsin. Primary outcome was rate of hospitalization at days 14, 21 and 28 after infusion. FINDINGS: The median age of the antibody-treated cohort was 63 years (interquartile range, 52-71); 45·5% were ≥65 years old; 51.4% were female. High-risk characteristics were hypertension (52.4%), body mass index ≥35 (31.0%), diabetes mellitus (24.6%), chronic lung disease (22.1%), chronic renal disease (11.4%), congestive heart failure (6.6%), and compromised immune function (6.7%). Compared to the propensity-matched untreated control, patients who received casirivimab-imdevimab had significantly lower all-cause hospitalization rates at day 14 (1.3% vs 3.3%; Absolute Difference: 2.0%; 95% confidence interval (CI): 0.5-3.7%), day 21 (1.3% vs 4.2%; Absolute Difference: 2.9%; 95% CI: 1.2-4.7%), and day 28 (1.6% vs 4.8%; Absolute Difference: 3.2%; 95% CI: 1.4-5.1%). Rates of intensive care unit admission and mortality at days 14, 21 and 28 were similarly low for antibody-treated and untreated groups. INTERPRETATION: Among high-risk patients with mild to moderate COVID-19, casirivimab-imdevimab treatment was associated with a significantly lower rate of hospitalization. FUNDING: Mayo Clinic.

Intravenous bamlanivimab use associates with reduced hospitalization in high-risk patients with mild to moderate COVID-19.

BACKGROUNDClinical data to support the use of bamlanivimab for the treatment of outpatients with mild to moderate coronavirus disease-19 (COVID-19) are needed.METHODS2335 Patients who received single-dose bamlanivimab infusion between November 12, 2020, and February 17, 2021, were compared with a propensity-matched control of 2335 untreated patients with mild to moderate COVID-19 at Mayo Clinic facilities across 4 states. The primary outcome was the rate of hospitalization at days 14, 21, and 28.RESULTSThe median age of the population was 63 years; 47.3% of the bamlanivimab-treated cohort were 65 years or more; 49.3% were female and 50.7% were male. High-risk characteristics included hypertension (54.2%), BMI greater than or equal to 35 (32.4%), diabetes mellitus (26.5%), chronic lung disease (25.1%), malignancy (16.6%), and renal disease (14.5%). Patients who received bamlanivimab had lower all-cause hospitalization rates at days 14 (1.5% vs. 3.5%; risk ratio [RR], 0.41), 21 (1.9% vs. 3.9%; RR, 0.49), and 28 (2.5% vs. 3.9%; RR, 0.63). Secondary exploratory outcomes included lower intensive care unit (ICU) admission rates at days 14 (0.14% vs. 1%; RR, 0.14), 21 (0.25% vs.1%; RR, 0.25), and 28 (0.56% vs.1.1%; RR. 0.51) and lower all-cause mortality at days 14 (0% vs. 0.33%), 21 (0.05% vs. 0.4%; RR,0.13), and 28 (0.11% vs. 0.44%; RR, 0.26). Adverse events were uncommon with bamlanivimab, occurring in 19 of 2355 patients, and were most commonly fever (n = 6), nausea (n = 5), and lightheadedness (n = 3).CONCLUSIONSAmong high-risk patients with mild to moderate COVID-19, treatment with bamlanivimab was associated with a statistically significant lower rate of hospitalization, ICU admission, and mortality compared with usual care.FUNDINGMayo Clinic.

Real-World Clinical Outcomes of Bamlanivimab and Casirivimab-Imdevimab Among High-Risk Patients With Mild to Moderate Coronavirus Disease 2019.

BACKGROUND: Bamlanivimab and casirivimab-imdevimab are authorized for treatment of mild to moderate coronavirus disease 2019 (COVID-19) in high-risk patients. We compared the outcomes of patients who received these therapies to identify factors associated with hospitalization and other clinical outcomes. METHODS: Adult patients who received monoclonal antibody from 19 November 2020 to 11 February 2021 were selected and divided into those who received bamlanivimab (n = 2747) and casirivimab-imdevimab (n = 849). The 28-day all-cause and COVID-19-related hospitalizations were compared between the groups. RESULTS: The population included 3596 patients; the median age was 62 years, and 50% were female. All had ≥1 medical comorbidity; 55% had multiple comorbidities. All-cause and COVID-19-related hospitalization rates at 28 days were 3.98% and 2.56%, respectively. After adjusting for medical comorbidities, there was no significant difference in all-cause and COVID-19-related hospitalization rates between bamlanivimab and casirivimab-imdevimab (adjusted hazard ratios [95% confidence interval], 1.4 [.9-2.2] and 1.6 [.8-2.7], respectively). Chronic kidney, respiratory and cardiovascular diseases, and immunocompromised status were associated with higher likelihood of hospitalization. CONCLUSIONS: This observational study on the use of bamlanivimab and casirivimab-imdevimab in high-risk patients showed similarly low rates of hospitalization. The number and type of medical comorbidities are associated with hospitalizations after monoclonal antibody treatment.

Association of Intravenous Bamlanivimab Use with Reduced Hospitalization, Intensive Care Unit Admission, and Mortality in Patients with Mild to Moderate COVID-19.

BACKGROUND: Clinical data to support the use of bamlanivimab for the treatment of outpatients with mild to moderate coronavirus disease-19 (COVID-19) is needed. METHODS: 2,335 patients who received single-dose bamlanivimab infusion between November 12, 2020 to February 17, 2021 were compared with a propensity-matched control of 2,335 untreated patients with mild to moderate COVID-19 at Mayo Clinic facilities across 4 states. The primary outcome was the rate of hospitalization at days 14, 21 and 28. RESULTS: The median age of the population was 63; 47.3% of the bamlanivimab-treated cohort were ≥65 years; 49.3% were female. High-risk characteristics included hypertension (54.2%), body mass index ≥35 (32.4%), diabetes mellitus (26.5%), chronic lung disease (25.1%), malignancy (16.6%), and renal disease (14.5%). Patients who received bamlanivimab had lower all-cause hospitalization rates at days 14 (1.5% vs 3.5%; Odds Ratio [OR], 0.38), 21 (1.9% vs 3.9%; OR, 0.46), and 28 (2.5% vs 3.9%; OR, 0.61). Secondary exploratory outcomes included lower intensive care unit admission rates at days 14 (0.14% vs 1%; OR, 0.12), 21 (0.25% vs 1%; OR: 0.24) and 28 (0.56% vs 1.1%; OR: 0.52), and lower all-cause mortality at days 14 (0% vs 0.33%), 21 (0.05% vs 0.4%; OR,0.08) and 28 (0.11% vs 0.44%; OR, 0.01). Adverse events were uncommon with bamlanivimab, occurring in 19/2355, most commonly fever (n=6), nausea (n=5), and lightheadedness (n=3). CONCLUSIONS: Among high-risk patients with mild to moderate COVID-19, treatment with bamlanivimab was associated with a statistically significant lower rate of hospitalization compared with usual care. FUNDING: Mayo Clinic.

A Framework for Outpatient Infusion of Antispike Monoclonal Antibodies to High-Risk Patients with Mild-to-Moderate Coronavirus Disease-19: The Mayo Clinic Model.

The administration of spike monoclonal antibody treatment to patients with mild to moderate COVID-19 is very challenging. This article summarizes essential components and processes in establishing an effective spike monoclonal antibody infusion program. Rapid identification of a dedicated physical infrastructure was essential to circumvent the logistical challenges of caring for infectious patients while maintaining compliance with regulations and ensuring the safety of our personnel and other patients. Our partnerships and collaborations among multiple different specialties and disciplines enabled contributions from personnel with specific expertise in medicine, nursing, pharmacy, infection prevention and control, electronic health record (EHR) informatics, compliance, legal, medical ethics, engineering, administration, and other critical areas. Clear communication and a culture in which all roles are welcomed at the planning and operational tables are critical to the rapid development and refinement needed to adapt and thrive in providing this time-sensitive beneficial therapy. Our partnerships with leaders and providers outside our institutions, including those who care for underserved populations, have promoted equity in the access of monoclonal antibodies in our regions. Strong support from institutional leadership facilitated expedited action when needed, from a physical, personnel, and system infrastructure standpoint. Our ongoing real-time assessment and monitoring of our clinical program allowed us to improve and optimize our processes to ensure that the needs of our patients with COVID-19 in the outpatient setting are met.