SARS-CoV-2 Pre-Exposure Prophylaxis with Sotrovimab and Tixagevimab/Cilgavimab in Immunocompromised Patients-A Single-Center Experience

Human monoclonal antibody F61 nasal spray effectively protected high-risk populations from SARS-CoV-2 variants during the COVID-19 pandemic from late 2022 to early 2023 in China

Following the national dynamic zero-COVID strategy adjustment, the utilization of broad-spectrum nasal neutralizing antibodies may offer an alternative approach to controlling the outbreak of Omicron variants between late 2022 and early 2023 in China. This study involved an investigator-initiated trial (IIT) to assess the pharmacokinetic, safety and efficacy of the F61 nasal spray. A total of 2,008 participants were randomly assigned to receive F61 nasal spray (24 mg/0.8 mL/dose) or normal saline (0.8 mL/dose) and 1336 completed the follow-up in the IIT. Minimal absorption of F61 antibody into the bloodstream was detected in individuals receiving F61 nasal spray for seven consecutive days. No treatment-emergent adverse reactions of grade 3 severity or higher were reported. In the one-dose cohort, the 7-day cumulative SARS-CoV-2 infection rate was 79.0% in the F61 group and 82.6% in the placebo group, whereas, in the multiple-dose (once daily for 7 consecutive days) cohort, the rates were 6.55% in the F61 group and 23.83% in the placebo group. The laboratory-confirmed efficacy of F61 was 3.78% (-3.74%-10.75%) in the one-dose cohort and 72.19% (57.33%-81.87%) in the multiple-dose cohort. In the real-world study, 60,225 volunteers in four different regions were administered the F61 nasal spray based on the subject's wishes, over 90% efficacy rate was observed against different Omicron variants. The F61 nasal spray, with its favourable safety profile, could be a promising prophylactic monoclonal antibody against SARS-CoV-2 VOCs.

An Overview of the Strategies to Boost SARS-CoV-2-Specific Immunity in People with Inborn Errors of Immunity

The SARS-CoV-2 pandemic has heightened concerns about immunological protection, especially for individuals with inborn errors of immunity (IEI). While COVID-19 vaccines elicit strong immune responses in healthy individuals, their effectiveness in IEI patients remains unclear, particularly against new viral variants and vaccine formulations. This uncertainty has led to anxiety, prolonged self-isolation, and repeated vaccinations with uncertain benefits among IEI patients. Despite some level of immune response from vaccination, the definition of protective immunity in IEI individuals is still unknown. Given their susceptibility to severe COVID-19, strategies such as immunoglobulin replacement therapy (IgRT) and monoclonal antibodies have been employed to provide passive immunity, and protection against both current and emerging variants. This review examines the efficacy of COVID-19 vaccines and antibody-based therapies in IEI patients, their capacity to recognize viral variants, and the necessary advances required for the ongoing protection of people with IEIs.

The efficacy of tixagevimab/cilgavimab (Evusheld) in prophylaxis and treatment of COVID-19 in immunocompromised patients: a systematic review and meta-analysis

BACKGROUND

During the COVID-19 pandemic, some populations, including immunocompromised patients, could not tolerate COVID-19 vaccination or had low responses. Evusheld is a combined neutralizing monoclonal antibody containing tixagevimab and cilgavimab. The World Health Organization (WHO) has approved this combination as pre-exposure prophylaxis (PrEP) and treatment for immunocompromised patients. With the new variant, the (WHO) recommended an increase in dose from 300 to 600 mg with a booster dose after 6 months. The target of this review was to compare the efficacy of the two doses, 300 mg and 600 mg of tixagevimab/cilgavimab (Evusheld) as prophylaxis for higher-risk individuals to reveal if there is a significant difference in efficacy between those two doses of the drug.

METHODS

In this study, electronic databases (PubMed, Web of Science core collection, Scopus, and Cochran) were investigated for articles up to 31/12/2022 in English using a well-established search strategy. We included studies conducted in immunocompromised patients (aged ≥ 12 years) (WHO) received Evusheld as prophylaxis or treatment for COVID-19. After excluding studies inconsistent with the selection criteria, 24 were involved, 22 of which were included in the meta-analysis. We analyzed the data by using RevMan 5.4 program software.

RESULTS

In the double-arm subgroup analysis, Evusheld 600 mg, administered as prophylaxis, showed no significant difference in the COVID-19 infection rate, mortality rate, or needed hospitalization rate compared with the dose of 300 mg (p = 0.13, p = 0.29, and p = 0.25, respectively). In the single-arm subgroup analysis, Evusheld 600 mg, administered as prophylaxis, showed a significant decrease in the COVID-19 infection rate and the hospitalization rate compared with the dose of 300 mg (p = 0.0001, p = 0.007, respectively). As a treatment, Evusheld showed a significant decrease in the mortality rate over the placebo group (p = 0.01) in COVID-19 patients.

CONCLUSION

This result indicated that Evusheld was an effective prophylactic and therapeutic drug for COVID-19 infection, especially for immunocompromised patients, but there was no considerable variation between the high and low doses. Further prospective and randomized controlled trials (RCTs) with increased population sizes are necessary to show the valuable benefit of the high dose of Evusheld in COVID-19 prevention and treatment and to compare the difference between the two doses within adverse events.

Immunogenicity and effectiveness of COVID-19 booster vaccination among people living with HIV: a systematic review and meta-analysis

Background

The effect of booster vaccinations with the coronavirus virus disease (COVID-19) vaccine on people living with HIV (PLWH) remains unknown. In this study, we aimed to investigate the immunogenicity and effectiveness of booster doses of the COVID-19 vaccine in PLWH.

Methods

Literature research was done through the PubMed, Embase, Cochrane Review, and Web of Science databases up to 4 July 2023. Pooled estimates were calculated and compared using the DerSimonian and Laird method for a random effects model. Randomized control trials and observational studies were both considered for inclusion.

Results

We included 35 eligible studies covering 30,154 PLWH. The pooled immune response rate (IRR) of PLWH after the COVID-19 booster vaccination was 97.25% (95% confidence interval [CI], 93.81-99.49), and similar to healthy control (HC) (risk ratio [RR] = 0.98, 95% CI, 0.96-1.00). The pooled IRR for PLWH with CD4+ T-cell counts ≤ 200 was 86.27 (95% CI, 65.35-99.07). For Omicron variants, the pooled IRR for PLWH after booster dose was 74.07% (95% CI, 58.83-89.30), and the risk of IRR was reduced by 10% in PLWH compared with HC (RR = 0.90, 95% CI, 0.80-1.00). The T-cell immune response of PLWH was found to be comparable to HC (p ≥ 0.05). Subgroup analyses revealed that mRNA vaccines produced a relatively high IRR in PLWH compared to other vaccines. In addition, the results showed that booster vaccination appeared to further reduce the risk of COVID-19-related infections, hospitalizations, and deaths compared with the primary vaccination.

Conclusion

It was shown that booster vaccination with the COVID-19 vaccine provided a high IRR in PLWH and still produced a desirable moderate IRR in PLWH with a CD4+ T-cell count of ≤ 200. Importantly, the humoral and T-cell responses to booster vaccination in PLWH were comparable to HC, and similar results were observed with the SARS-CoV-2 Omicron variant. Our review strongly emphasizes the effect of mRNA vaccine booster vaccination in PLWH on eliciting desirable protective IRR. Furthermore, booster vaccination appears to further reduce the risk of COVID-19 infection, hospitalization, and death in PLWH compared to primary vaccination. However, more evidence is needed to confirm its effectiveness.

A Model-Based Cost-Effectiveness Analysis of Long-Acting Monoclonal Antibody (Tixagevimab and Cilgavimab: Evusheld) Preventive Treatment for High-Risk Populations Against SARS-CoV-2 in Korea

BACKGROUND

Tixagevimab and cilgavimab (Evusheld) administration is a recommended strategy for unvaccinated patients with immunocompromised conditions and severe allergic reaction conditions to protect high-risk individuals and control the coronavirus disease 2019 (COVID-19) epidemic. We estimated the cost-effectiveness of Evusheld in key risk populations: 1) immunocompromised (vaccinated/unvaccinated), 2) severe allergic reaction, and 3) unvaccinated elderly high-risk groups.

METHODS

Based on the estimated target risk group population, we used a model of COVID-19 transmission to estimate the size of the risk group population for whom Evusheld treatment may help prevent symptomatic COVID-19 (and deaths) in 2022. We projected Evusheld intervention costs, quality-adjusted life year (QALY) lost, cost averted and QALY gained by reduced COVID-19 incidence, and incremental cost-effectiveness (cost per QALY gained) in each modeled population from the healthcare system perspective.

RESULTS

Our study demonstrated that Evusheld treatment for COVID-19 infection in South Korea is highly cost-effective for unvaccinated risk groups ($18,959 per QALY gained for immunocompromised and $23,978 per QALY gained for high-risk elderly groups) and moderately cost-effective among individuals who are vaccinated immunocompromised ($46,494 per QALY gained), or have severe allergic reactions ($45,996 per QALY gained). Evusheld's cost-effectiveness may be subject to risk-group-specific COVID-19 disease progression and Evusheld efficacy and cost, which may change in future epidemic scenarios.

CONCLUSION

As the COVID-19 variants and risk group-specific durable efficacy, toxicity (and/or resistance) and optimal dosing of Evusheld remain uncertain, better empirical estimates to inform these values in different epidemiological contexts are needed. These results may help decision-makers prioritize resources toward more equitable and effective COVID-19 control efforts.

Monitoring of Sotrovimab-Levels as Pre-Exposure Prophylaxis in Kidney Transplant Recipients Not Responding to SARS-CoV-2 Vaccines

Background Sotrovimab, a monoclonal antibody against SARS-CoV-2, is used as a pre-exposition prophylaxis (PrEP) against COVID-19, but monitoring strategies using routine test systems have not been defined. Methods Twenty kidney transplant recipients without antibodies after vaccination received 500 mg Sotrovimab. Antibody levels were quantified over eight weeks using live-virus neutralization (BA1 and BA2), antibody binding assays (TrimericS, Elecsys, QuantiVAC) and surrogate virus neutralization tests (sVNTs; TECOmedical, cPass and NeutraLISA). Results Sotrovimab neutralized both Omicron subvariants (BA1 NT titer 90 (+-50) > BA2 NT titer 33 (+-15) one hour post infusion). Sotrovimab was measurable on all used immunoassays, although a prior 1:100 dilution was necessary for Elecsys due to a presumed prozone effect. The best correlation with live-virus neutralization titers was found for QuantiVAC and TrimericS, with a respective R2 of 0.65/0.59 and 0.76/0.57 against BA1/BA2. Elecsys showed an R2 of 0.56/0.54 for BA1/BA2, respectively. sVNT values increased after infusion but had only a poor correlation with live-virus neutralization titers (TECOmedical and cPass) or did not reach positivity thresholds (NeutraLISA). Conclusion Antibody measurements by the used immunoassays showed differences in antibody levels and only a limited correlation with neutralization capacity. We do not recommend sVNTs for monitoring SARS-CoV-2 neutralization by Sotrovimab.

Prevention of COVID-19 Following a Single Intramuscular Administration of Adintrevimab: Results From a Phase 2/3 Randomized, Double-Blind, Placebo-Controlled Trial (EVADE)

Background

The prevention of coronavirus disease 2019 (COVID-19) in vulnerable populations is a global health priority. EVADE was a phase 2/3 multicenter, double-blind, randomized, placebo-controlled trial of adintrevimab, an extended-half-life monoclonal antibody, for postexposure (PEP) and pre-exposure prophylaxis (PrEP) of symptomatic COVID-19.

Methods

Eligible participants (vaccine-naive, aged ≥12 years) were randomized 1:1 to receive a single 300-mg intramuscular injection of adintrevimab or placebo. Primary efficacy end points were reverse transcription polymerase chain reaction (RT-PCR)-confirmed symptomatic COVID-19 through day 28 in the PEP cohort (RT-PCR-negative at baseline) and through month 3 in the PrEP cohort (RT-PCR-negative and seronegative at baseline) among participants randomized before emergence of the severe acute respiratory syndrome coronavirus 2 Omicron variant (November 30, 2021). Safety was assessed through 6 months.

Results

Between April 27, 2021, and January 11, 2022, 2582 participants were randomized. In the primary efficacy analysis, RT-PCR-confirmed symptomatic COVID-19 occurred in 3/175 (1.7%) vs 12/176 (6.8%) adintrevimab- and placebo-treated PEP participants, respectively (74.9% relative risk reduction [RRR]; standardized risk difference, -5.0%; 95% CI, -8.87% to -1.08%; P = .0123) and in 12/752 (1.6%) vs 40/728 (5.5%) adintrevimab- and placebo-treated PrEP participants, respectively (71.0% RRR; standardized risk difference, -3.9%; 95% CI, -5.75% to -2.01%; P < .0001). In a prespecified exploratory analysis of 428 PrEP participants randomized after the emergence of Omicron, adintrevimab reduced RT-PCR-confirmed symptomatic COVID-19 by 40.6% (standardized risk difference -8.4%; 95% CI, -15.35% to -1.46%; nominal P = .0177) vs placebo. Adintrevimab was well tolerated, with no serious drug-related adverse events reported.

Conclusions

A single intramuscular injection of adintrevimab provided prophylactic efficacy against COVID-19 due to susceptible variants without safety concerns. Clinical trial registration. NCT04859517.

Tixagevimab/Cilgavimab as pre-exposure prophylaxis against SARS-CoV-2 in patients with hematological malignancies

The approved combination of Tixagevimab/Cilgavimab has been shown to decrease the rate of symptomatic SARS-CoV-2 infection in patients at increased risk of inadequate response to vaccination. However, Tixagevimab/Cilgavimab was tested in a few studies that included patients with hematological malignancies, even if this population has shown an increased risk of unfavorable outcomes following infection (with high rates of hospitalization, intensive care unit admission, and mortality) and poor significant immunization following vaccines. We performed a real-life prospective cohort study to evaluate the rate of SARS-CoV-2 infection following pre-exposure prophylaxis with Tixagevimab/Cilgavimab in anti-spike seronegative patients compared to a cohort of seropositive patients who were observed or received a fourth vaccine dose. We recruited 103 patients with a mean age of 67 years: 35 (34%) received Tixagevimab/Cilgavimab and were followed from March 17, 2022, until November 15, 2022. After a median follow-up of 4.24 months, the 3-month cumulative incidence of infection was 20% versus 12% in the Tixagevimab/Cilgavimab and observation/vaccine groups respectively (HR 1.57; 95% CI: 0.65-3.56; p = 0.34). In this study, we report our experience with Tixagevimab/Cilgavimab and a tailored approach to SARS-CoV-2 infection prevention in patients with hematological malignancies during the SARS-CoV-2 omicron surge.

Pre-exposure prophylaxis of new COVID-19 coronavirus infection with tixagevimab/cilgavimab in adult Moscow patients with primary immunodeficiencies

Background. Primary immunodeficiencies (PIDs), now known as inborn errors of immunity, are a group of inherited diseases caused by defects in the genes that control the immune response. Patients with PIDs have risks of developing a severe course and/or death in COVID-19. Passive immunization with long-acting monoclonal antibodies (MABs) to SARS-CoV-2 should be considered as pre-exposure prophylaxis in patients with PIDs. Tixagevimab/cilgavimab is a combination of MABs that bind to the SARS-CoV-2 spike protein. Aim. To evaluate the efficacy and safety of pre-exposure prophylaxis of new SARS-CoV-2 infection in PIDs with the combination of tixagevimab/cilgavimab. Materials and methods. Forty eight patients diagnosed with PIDs were included in the study. Median follow-up after drug administration was 174 days. The total number of confirmed coronavirus infections in patients with PIDs as well as 6 months before and after administration of MAT were assessed. Results. In the analyzed cohort, the overall incidence of COVID-19 from pandemic onset to MABs administration was 75% (36/48), with 31% (11/36) of over-infected patients having had the infection more than once. The incidence of COVID-19 immediately 6 months before the introduction of tixagevimab/cilgavimab was 40%. All patients who had COVID-19 after pre-exposure prophylaxis had a mild infection. The incidence of COVID-19 6 months after tixagevimab/cilgavimab administration significantly decreased compared to the incidence 6 months before administration (7 and 40%, respectively; p0.001). Conclusion. The use of tixagevimab/cilgavimab in patients with PIDs is effective as pre-exposure prophylaxis and reduces the risk of severe COVID-19.

Efficacy and Safety of Tixagevimab/Cilgavimab to Prevent COVID-19 (Pre-Exposure Prophylaxis): A Systematic Review and Meta-Analysis

Background: Tixagevimab/cilgavimab (TGM/CGM) are neutralizing monoclonal antibodies (mAbs) directed against different epitopes of the receptor-binding domain of the SARS-CoV-2 spike protein that have been considered as pre-exposure prophylaxis (PrEP). Objectives: This study seeks to assess the efficacy and safety of TGM/CGM to prevent COVID-19 in patients at high risk for breakthrough and severe SARS-CoV-2 infection who never benefited maximally from SARS-CoV-2 vaccination and for those who have a contraindication to SARS-CoV-2 vaccines. Design: This study is a systematic review and meta-analysis. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Methods: Electronic databases (PubMed, CINAHL, Embase, medRxiv, ProQuest, Wiley online library, Medline, and Nature) were searched from 1 December 2021 to 30 November 2022 in the English language using the following keywords alone or in combination: 2019-nCoV, 2019 novel coronavirus, COVID-19, coronavirus disease 2019, SARS-CoV-2, severe acute respiratory syndrome coronavirus 2, tixagevimab, cilgavimab, combination, monoclonal, passive, immunization, antibody, efficacy, clinical trial, cohort, pre-exposure, prophylaxis, and prevention. We included studies in moderate to severe immunocompromised adults (aged ≥18 years) and children (aged ≥12 years) who cannot be vaccinated against COVID-19 or may have an inadequate response to SARS-CoV-2 vaccination. The effect sizes of the outcome of measures were pooled with 95% confidence intervals (CIs) and risk ratios (RRs). Results: Of the 76 papers that were identified, 30 articles were included in the qualitative analysis and 13 articles were included in the quantitative analysis (23 cohorts, 5 case series, 1 care report, and 1 randomized clinical trial). Studies involving 27,932 patients with high risk for breakthrough and severe COVID-19 that reported use of TGM/CGM combination were analyzed (all were adults (100%), 62.8% were men, and patients were mainly immunocompromised (66.6%)). The patients’ ages ranged from 19.7 years to 79.8 years across studies. TGM/CGM use was associated with lower COVID-19-related hospitalization rate (0.54% vs. 1.2%, p = 0.27), lower ICU admission rate (0.6% vs. 5.2%, p = 0.68), lower mortality rate (0.2% vs. 1.2%, p = 0.67), higher neutralization of COVID-19 Omicron variant rate (12.9% vs. 6%, p = 0.60), lower proportion of patients who needed oxygen therapy (8% vs. 41.2%, p = 0.27), lower RT-PCR SARS-CoV-2 positivity rate (2.1% vs. 5.8%, p < 0.01), lower proportion of patients who had severe COVID-19 (0% vs. 0.5%, p = 0.79), lower proportion of patients who had symptomatic COVID-19 (1.8% vs. 6%, p = 0.22), and higher adverse effects rate (11.1% vs. 10.7%, p = 0.0066) than no treatment or other alternative treatment in the prevention of COVID-19. Conclusion: For PrEP, TGM/CGM-based treatment can be associated with a better clinical outcome than no treatment or other alternative treatment. However, more randomized control trials are warranted to confirm our findings and investigate the efficacy and safety of TGM/CGM to prevent COVID-19 in patients at risk for breakthrough or severe SARS-CoV-2 infection.