Clinical outcomes of mild to moderate coronavirus disease 2019 patients treated with Regdanvimab in delta-variant outbreak: Retrospective cohort study

Regdanvimab is a novel neutralizing antibody agent used for the treatment of coronavirus disease 2019 (COVID-19). However, the effectiveness of regdanvimab in delta-variant patients has rarely been investigated. We examined the clinical outcomes and adverse events in COVID 19 patients treated with regdanvimab in the delta-variant era. Data were collected from laboratory-confirmed COVID-19 hospitalized patients who received regdanvimab in 2021 and categorized into pre-delta and delta variant groups. The primary outcome was the need for oxygen therapy. Rescue therapy, clinical improvement, and adverse events were analyzed. Among 101 patients treated with regdanvimab, 31 (30.7%) were delta patients and 49 (48.5) were pre-delta patients. 64.4% were male, the mean age was 60.3 years, and 70 patients (69%) had at least one underlying disease. The median interval from symptom onset to injection was 4 days. Twenty-three patients (23%) needed oxygen therapy, including 9 (29%) in the delta and 8 (16.3%) in the pre-delta group. (P = .176) The risk of early oxygen supplement was higher in the delta group (adjusted hazard ratio (aHR), 6.75; 95% confidence interval(CI), 1.53-29.8). The in-hospital survival rate was 100%, and no patients were admitted to the intensive care unit. Adverse events occurred in 43% of patients:13 (42%) delta patients and 23 (47%) pre-delta patients had any adverse events (P = .661). Patients treated with regdanvimab 4 days after symptom onset showed a favorable prognosis (aHR, 0.26; 95% CI, 0.26-0.91). We found that the high-risk mild to moderate COVID-19 patients treated with regdanvimab showed similar disease progression in delta-variant patients and pre-delta variants; however, we need to be more closely observed delta-variant patients than those in the pre-delta group despite regdanvimab treatment due to rapid disease aggravation.

Effectiveness of regdanvimab treatment for SARS-CoV-2 delta variant, which exhibited decreased in vitro activity: a nationwide real-world multicenter cohort study

Background

Immune-evading severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are emerging continuously. The clinical effectiveness of monoclonal antibody agents that exhibit decreased in vitro activity against SARS-CoV-2 variants needs to be elucidated.

Methods

A nationwide, multicenter, retrospective cohort study was designed to evaluate the effectiveness of regdanvimab, an anti-SARS-CoV-2 monoclonal antibody agent. Regdanvimab was prescribed in South Korea before and after the emergence of the delta variant, against which the in vitro activity of regdanvimab was decreased but present. Mild to moderate coronavirus 2019 (COVID-19) patients with risk factors for disease progression who were admitted within seven days of symptom onset were screened in four designated hospitals between December 2020 and September 2021. The primary outcomes, O₂ requirements and progression to severe disease within 21 days of admission, were compared between the regdanvimab and supportive care groups, with a subgroup analysis of delta variant-confirmed patients.

Results

A total of 2,214 mild to moderate COVID-19 patients were included, of whom 1,095 (49.5%) received regdanvimab treatment. In the analysis of the total cohort, significantly fewer patients in the regdanvimab group than the supportive care group required O₂ support (18.4% vs. 27.1%, P < 0.001) and progressed to severe disease (4.0% vs. 8.0%, P < 0.001). In the multivariable analysis, regdanvimab was significantly associated with a decreased risk for O₂ support (HR 0.677, 95% CI 0.561-0.816) and progression to severe disease (HR 0.489, 95% CI 0.337-0.709). Among the 939 delta-confirmed patients, O₂ support (21.5% vs. 23.5%, P = 0.526) and progression to severe disease (4.2% vs. 7.3%, P = 0.055) did not differ significantly between the regdanvimab and supportive care groups. In the multivariable analyses, regdanvimab treatment was not significantly associated with a decreased risk for O₂ support (HR 0.963, 95% CI 0.697-1.329) or progression to severe disease (HR 0.665, 95% CI 0.349-1.268) in delta-confirmed group.

Conclusions

Regdanvimab treatment effectively reduced progression to severe disease in the overall study population, but did not show significant effectiveness in the delta-confirmed patients. The effectiveness of dose increment of monoclonal antibody agents should be evaluated for variant strains exhibiting reduced susceptibility.

Efficacy and safety of regdanvimab in patients with mild to moderate COVID-19: A rapid review and meta-analysis

AIMS

This study aimed to evaluate the efficacy and safety of regdanvimab, an anti-SARS-COV-2 monoclonal antibody approved by the European Medicines Agency in November 2021, for the treatment of confirmed COVID-19 disease.

METHODS

Cochrane Library, PubMed, medRxiv and Google Scholar were searched for relevant evidence up to October 27, 2022. The quality of included studies was assessed using the Cochrane risk of bias tools. Data were analysed using RevMan software.

RESULTS

Eight studies involving 4793 patients were included. A significant difference was observed between the regdanvimab and no-regdanvimab groups in terms of length of hospital stay (mean difference [MD] = -1.15, 95% confidence interval [CI]: -1.80 to -0.43), clinical recovery (odds ratio [OR] = 2.09, 95% CI: 1.38 to 3.18), disease progression (OR = 0.23, 95% CI: 0.16 to 0.33), the need for oxygen therapy (OR = 0.33, 95% CI: 0.25 to 0.43) and duration of oxygen therapy (MD = -3.00, 95% CI: -4.44 to -1.56). However, no significant difference was detected between 2 groups regarding mortality rate (OR = 0.46, 95% CI: 0.11 to 1.89), need for mechanical ventilation (OR = 0.39, 95% CI: 0.08 to 1.89) and hospital admission rate (OR = 0.61, 95% CI: 0.35 to 1.03). The incidence of adverse events was similar in both groups (OR = 0.96, 95% CI: 0.77 to 1.18).

CONCLUSION

Regdanvimab was not effective in reducing mortality and hospital admission rate in patients with mild to moderate COVID-19, but it was effective in improving other efficacy outcomes. Further research is needed to confirm these findings.

Haploidentical CD3+ TCR αβ/CD19+-depleted HSCT for MHC class II deficiency and persistent SARS-CoV-2 pneumonitis

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection leads to coronavirus disease 2019 (COVID-19), which can range from a mild illness to a severe phenotype characterized by acute respiratory distress needing mechanical ventilation. Children with combined immunodeficiencies might be unable to mount a sufficient cellular and humoral immune response against COVID-19 and have persistent disease.

Objective

Our aim was to describe a child with combined immunodeficiency and a favorable post-hematopoietic stem cell transplant (HSCT) course following a haploidentical HSCT in the presence of persistent SARS-CoV-2 infection.

Methods

A 13-month-old girl with MHC class II deficiency developed persistent pre-HSCT SARS-CoV-2 infection. Faced with a significant challenge of balancing the risk of progressive infection due to an incompetent immune system with the danger of inflammatory pneumonitis peri-immune reconstitution after HSCT, the patient's physicians performed a maternal (with a recent history of COVID-19 infection) haploidentical HSCT. The patient received regdanvimab (after stem cell infusion) and remdesivir (before and after stem cell infusion).

Results

The patient exhibited a gradual increase in her cycle threshold values, implying a reduction in viral RNA with concomitant expansion in the CD3 lymphocyte subset and clinical and radiologic improvement.

Conclusions

Combination of adoptive transfer of maternal CD45RO⁺ memory addback T lymphocytes after haploidentical HSCT and use of regdanvimab (a SARS-CoV-2-neutralizing mAb) and remdesivir may have led to the successful outcome in our patient with severe immunodeficiency after she had undergone HSCT. This case highlights the role of novel antiviral strategies (mAbs and CD45RO⁺ memory T lymphocytes) in contributing to viral clearance in a challenging clinical scenario.

Regdanvimab for patients with mild-to-moderate COVID-19: a retrospective cohort study and subgroup analysis of patients with the Delta variant

OBJECTIVES

To evaluate efficacy and safety of regdanvimab, a neutralizing antibody, in patients with mild-to-moderate severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) including against the Delta variant.

METHODS

A single-center, retrospective, observational cohort study in adults with confirmed coronavirus disease 2019 (COVID-19). The primary endpoint was the proportion of patients deteriorating with peripheral oxygen saturation <90% in room air, requiring supplemental oxygen therapy above high flow, or experiencing mortality due to COVID-19 up to Day 28.

RESULTS

722 patients were eligible; 418 received regdanvimab and 304 received standard of care (SoC) of whom 71.1% (297/418, regdanvimab) and 37.8% (115/304, SoC) were infected with the Delta variant. The proportion of patients with a primary endpoint event was significantly lower with regdanvimab versus SoC (3.1% vs 9.9%; difference: -6.8 [95% confidence interval: -10.9, -2.8]; P=0.0002). A similar trend was observed in the Delta variant subgroup (regdanvimab, 2.7% vs SoC, 7.0%; difference -4.3 [95% CI: -10.8, 0.2]; P=0.0827). Secondary efficacy endpoints supported primary analysis findings in the overall cohort and Delta variant subgroup. No new safety signals were identified.

CONCLUSIONS

Regdanvimab demonstrated clinical efficacy in the overall cohort and may provide a clinical benefit for patients with mild-to-moderate COVID-19, infected with the Delta variant.

Monoclonal antibody therapies in the management of SARS-CoV-2 infection

Introduction

Neutralizing antibodies (NAbs) that target key domains of the spike protein in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may have therapeutic value because of their specificity. Depending on the targeted epitope, single agents may be effective, but combined treatment involving multiple NAbs may be necessary to prevent the emergence of resistant variants.

Areas covered

This article highlights the accelerated regulatory processes established to facilitate the review and approval of potential therapies. An overview of treatment approaches for SARS-CoV-2 infection, with detailed examination of the preclinical and clinical evidence supporting the use of NAbs, is provided. Finally, insights are offered into the potential benefits and challenges associated with the use of these agents.

Expert opinion

NAbs offer an effective, evidence-based therapeutic intervention during the early stages of SARS-CoV-2 infection when viral replication is the primary factor driving disease progression. As the pandemic progresses, appropriate use of NAbs will be important to minimize the risk of escape variants. Ultimately, the availability of effective treatments for COVID-19 will allow the establishment of treatment algorithms for minimizing the substantial rates of hospitalization, morbidity (including long COVID) and mortality currently associated with the disease.

Safety, Virologic Efficacy, and Pharmacokinetics of CT-P59, a Neutralizing Monoclonal Antibody Against SARS-CoV-2 Spike Receptor-Binding Protein: Two Randomized, Placebo-Controlled, Phase I Studies in Healthy Individuals and Patients With Mild SARS-CoV-2 Infection

Purpose

Neutralizing antibodies can reduce SARS-CoV-2 cellular entry, viral titers, and pathologic damage. CT-P59 (regdanvimab), a SARS-CoV-2 neutralizing monoclonal antibody, was examined in 2 randomized, double-blind, placebo-controlled, single ascending dose, Phase I studies.

Methods

In study 1.1, healthy adults were sequentially enrolled to receive CT-P59 10, 20, 40, or 80 mg/kg or placebo. In study 1.2, adult patients with mild SARS-CoV-2 infection were enrolled to receive CT-P59 20, 40, or 80 mg/kg or placebo. Primary objectives of both studies were safety and tolerability up to day 14 after infusion. Secondary end points included pharmacokinetic properties. Study 1.2 also measured virology and clinical efficacy.

Findings

Thirty-two individuals were randomized to study 1.1 (6 per CT-P59 dose cohort and 8 in the placebo cohort). By day 14 after infusion, adverse events (AEs) were reported in 2 individuals receiving CT-P59 20 mg/kg (headache and elevated C-reactive protein levels) and 1 receiving CT-P59 40 mg/kg (pyrexia) (all Common Terminology Criteria for Adverse Events grade 1). In study 1.2, 18 patients were randomized (5 per dose cohort and 3 in the placebo cohort). Sixteen AEs were reported in 10 patients receiving CT-P59. No AEs in either study led to study discontinuation. Greater reductions in viral titers were reported with CT-P59 than placebo in those with maximum titers >10⁵ copies/mL. Mean time to recovery was 3.39 versus 5.25 days.

Implications

CT-P59 exhibited a promising safety profile in healthy individuals and patients with mild SARS-CoV-2 infection, with potential antiviral and clinical efficacy in patients with mild SARS-CoV-2 infection. ClinicalTrials.gov identifier: NCT04525079 (study 1.1) and NCT04593641 (study 1.2).