Use of Monoclonal Antibodies in Immunocompromised Patients Hospitalized with Severe COVID-19: A Retrospective Multicenter Cohort

Efficacy and safety of antiviral plus anti-spike monoclonal antibody combination therapy vs. monotherapy for high-risk immunocompromised patients with mild-to-moderate SARS-CoV2 infection during the Omicron era: A prospective cohort study

INTRODUCTION

Antivirals and monoclonal antibodies lower the risk of progression in immunocompromised patients. However, combination therapy with both types of agents has not been studied.

PATIENTS AND METHODS

This was a single-centre, prospective, cohort study. All immunocompromised patients who received treatment for mild-to-moderate COVID-19 from 1 January 2022 to 30 October 2022 were enrolled. The primary endpoint was COVID-19 progression at 90 days, defined as hospital admission or death due to COVID-19 and/or seronegative persistent COVID-19.

RESULTS

A total of 304 patients were included: 43 patients (14.1%) received sotrovimab plus a direct-acting antiviral, and 261 (85.9%) received monotherapy. Primary outcome occurred more frequently after monotherapy (4.6% vs. 0%, P=0.154). Among patients with anti-spike immunoglobulin G (anti-S IgG) titre <750 BAU/mL, COVID-19 progression was more common after monotherapy (23.9% vs. 0%, P=0.001), including more frequent COVID-related admission (15.2% vs. 0%, P=0.014) and seronegative persistent COVID-19 (10.9% vs. 0%, P=0.044). Combination therapy was associated with lower risk of progression (odds ratio [OR] 0.08, 95% confidence interval [95% CI] 0.01-0.64). Anti-S IgG titre <750 BAU/mL and previous anti-CD20 were associated with higher risk of progression (OR 13.70, 95% CI 2.77-67.68; and OR 3.05, 95% CI 1.20-10.94, respectively).

CONCLUSIONS

In immunocompromised patients, combination therapy with sotrovimab plus an antiviral may be more effective than monotherapy for SARS-CoV2.

Real-World Effectiveness of Sotrovimab for the Early Treatment of COVID-19: Evidence from the US National COVID Cohort Collaborative (N3C)

BACKGROUND AND OBJECTIVE

The coronavirus disease 2019 (COVID-19) pandemic has been an unprecedented healthcare crisis, one that threatened to overwhelm health systems and prompted an urgent need for early treatment options for patients with mild-to-moderate COVID-19 at high risk for progression to severe disease. Randomised clinical trials established the safety and efficacy of monoclonal antibodies (mAbs) early in the pandemic; in vitro data subsequently led to use of the mAbs being discontinued, without clear evidence on how these data were linked to outcomes. In this study, we describe and compare real-world outcomes for patients with mild-to-moderate COVID-19 at high risk for progression to severe COVID-19 treated with sotrovimab versus untreated patients.

METHODS

Electronic health records from the National COVID Cohort Collaborative (N3C) were used to identify US patients (aged ≥ 12 years) diagnosed with COVID-19 (positive test or ICD-10: U07.1) in an ambulatory setting (27 September 2021-30 April 2022) who met Emergency Use Authorization (EUA) high-risk criteria. Patients receiving the mAb sotrovimab within 10 days of diagnosis were assigned to the sotrovimab cohort, with the day of infusion as the index date. Untreated patients (no evidence of early mAb treatment, prophylactic mAb or oral antiviral treatment) were assigned to the untreated cohort, with an imputed index date based on the time distribution between diagnosis and sotrovimab infusion in the sotrovimab cohort. The primary endpoint was hospitalisation or death (both all-cause) within 29 days of index, reported as descriptive rate and adjusted [via inverse probability of treatment weighting (IPTW)] odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Of nearly 2.9 million patients diagnosed with COVID-19 during the analysis period, 4992 met the criteria for the sotrovimab cohort, and 541,325 were included in the untreated cohort. Before weighting, significant differences were noted between the cohorts; for example, patients in the sotrovimab cohort were older (60 years versus 54 years), were more likely to be white (85% versus 75%) and met more EUA criteria (mean 3.1 versus 2.2) versus the untreated cohort. The proportions of patients with 29-day hospitalisation or death were 3.5% (176/4992) and 4.5% (24,163/541,325) in the sotrovimab and untreated cohorts, respectively (unadjusted OR: 0.78; 95% CI: 0.67, 0.91; p = 0.001). In adjusted analysis, sotrovimab was associated with a 25% reduction in the odds of hospitalisation or death compared with the untreated cohort (IPTW-adjusted OR: 0.75; 95% CI: 0.61, 0.92; p = 0.005).

CONCLUSIONS

Sotrovimab demonstrated clinical effectiveness in preventing severe outcomes (hospitalisation, mortality) in the period 27 September 2021-30 April 2022, which included Delta and Omicron BA.1 variants and an early surge of Omicron BA.2 variant.

Clinical experience in the treatment of COVID-19 with monoclonal antibodies in solid organ transplant recipients

Solid organ transplant (SOT) recipients are at high risk for complications from coronavirus disease 2019 (COVID-19). SOT recipients mount lower immunological responses to vaccines than general population and are at high risk for breakthrough COVID-19 infections. Passive immunotherapy in the form of anti-Spike monoclonal antibodies (MoAbs) may be an alternative for the prophylaxis and treatment of COVID-19 in these patients. SARS-CoV-2 has evolved by accumulating resistance mutations that have escaped the neutralizing action of most MoAbs. However, MoAbs directed at more conserved epitopes and that maintain effector functions could maintain efficacy in the treatment of these patients. According to published data, SOT recipients with low anti-spike antibody responses to vaccination could benefit from the use of MoAbs in pre-exposure prophylaxis, in the treatment of COVID-19 mild to moderate and severe COVID-19 with less than 15 days of symptom duration and low oxygen requirements. Combination therapy could be more effective than monotherapy for the treatment of mild-to-moderate SARS-CoV-2 infection.

Resistance analysis following sotrovimab treatment in participants with COVID-19 during the phase III COMET-ICE study

Aim: Sotrovimab is an engineered human monoclonal antibody that binds a conserved region of the SARS-CoV-2 spike protein. The COMET-ICE phase III study evaluated sotrovimab for treatment of mild to moderate COVID-19 in nonhospitalized participants with ≥1 risk factor for severe disease progression. Materials & methods: We evaluated the presence of circulating SARS-CoV-2 variants of concern or interest (VOCs/VOIs) and characterized the presence of baseline, post-baseline and emergent amino acid substitutions detected in the epitope of sotrovimab in SARS-CoV-2. Results: None of the sotrovimab-treated participants with baseline epitope substitutions, and 1 of 48 sotrovimab-treated participants with post-baseline epitope substitutions, met the primary clinical endpoint for progression. Conclusion: Overall, progression was not associated with identified VOC/VOI or the presence of epitope substitutions in sotrovimab-treated participants.

Monoclonal antibodies as COVID-19 prophylaxis therapy in immunocompromised patient populations

OBJECTIVES

The objective of this review was to examine the latest literature regarding the effectiveness of monoclonal antibodies as COVID-19 prophylaxis therapy for immunocompromised patient populations.

METHODS

Literature review of published real-world and randomized control trials (RCTs) from 2020 to May 2023.

RESULTS

COVID-19 is highly transmissible with potentially serious health outcomes, underscoring the need for effective prevention and treatment strategies. Vaccines are highly effective at preventing COVID-19 for the general population; however, efficacy is often impaired in immunocompromised patients given insufficient response to initial exposure and/or memory for secondary exposures. Some individuals may also have contraindications to vaccination. As such, additional protective measures are needed to bolster the immune response in these populations. Monoclonal antibodies have been effective at bolstering immune system responses to COVID-19 among immunocompromised patients; however, they are proving ineffective against the most recent Omicron strains (BA.4 and BA.5).

CONCLUSION

Several studies have investigated the efficacy of monoclonal antibodies as pre- and post-prophylaxis for COVID-19. Historical evidence is promising; however, new variants of concern are proving challenging for currently available regimens.