ABSTRACT
Background/Aims Immunocompromised patients have a reduced ability to generate antibodies after COVID-19 vaccination, and are at a high risk of SARSPOSTERS CoV-2 infection, complications and mortality. Tixagevimab/Cilgavimab (Evusheld) is a combination of two monoclonal antibodies which bind to the SARS-CoV-2 spike protein, preventing the virus entering human cells. Tixagevimab/Cilgavimab has been approved as COVID-19 prophylaxis for immunocompromised individuals, and is being used in over 32 different countries. The phase III PROVENT clinical trial found that high-risk participants prophylactically administered Tixagevimab/Cilgavimab had a significantly reduced risk of COVID- 19 infection after three and six months compared to controls. However, the PROVENT trial was conducted prior to the SARS-CoV- 2 Omicron wave, and did not include participants who had been previously vaccinated or infected. This systematic review provides an updated summary of the real-world clinical evidence of the efficacy of Tixagevimab/Cilgavimab for immunocompromised patients. The review reports breakthrough COVID-19 infections as its primary outcome. COVID-19-related hospitalisations, ITU admissions and mortality were included as secondary outcomes. Methods Two independent reviewers conducted electronic searches of PubMed and Medxriv, on 03/08/22 and 01/10/22. Clinical studies which reported the primary outcome of breakthrough COVID-19 infections after Tixagevimab/Cilgavimab administration were included. Clinical effectiveness was determined using the case-control clinical effectiveness methodology. Odds ratios and 95% confidence intervals (CI) between intervention and control groups were also calculated. The GRADE tool was used to assess the level of certainty for the primary outcome. Results 17 clinical studies were included in the review, with a total of 24,773 immunocompromised participants from across the world, of whom 10,775 received Tixagevimab/Cilgavimab. One randomised controlled trial, ten retrospective cohort studies (two of which were preprints) and six prospective cohort studies (one preprint) were included. The majority of studies reported clinical outcomes during the SARS-CoV-2 Omicron wave. Six studies compared a Tixagevimab/Cilgavimab intervention group to a control group. Reasons for participant immunocompromise included rheumatology patients treated with immunosuppressant drugs, transplant recipients and those with malignancies. Overall, the clinical effectiveness of prophylactic Tixagevimab/Cilgavimab against COVID- 19 breakthrough infection was 40.47% (CI 29.82-49.67;p<0.0001), COVID-19 hospitalisation- 69.23% (CI: 50.78-81.64;p<0.00001), ITU admission- 87.89% (CI: 47.12-98.66;p=0.0008), all-cause mortality- 81.29% (66.93-90.28;p<0.0001 and COVID-19-specifc mortality- 86.36% (CI:-6.21-99.70;p=0.0351). Conclusion There is a growing body of real-world evidence validating the original PROVENT phase III study regarding the clinical effectiveness of Tixagevimab/Cilgavimab as prophylaxis for immunocompromised groups, notably demonstrating effectiveness during the Omicron wave. This systematic review demonstrates the significant clinical effectiveness of prophylactic Tixagevimb/Cilgavimab at reducing COVID-19 infection, hospitalisation, ITU admission and mortality for immunosuppressed individuals. It is critically important that largerscale and better-controlled studies are performed to highlight the significant clinical benefit of prophylactic antibody treatment in immunocompromised groups.
ABSTRACT
As a small group of academicians in a private medical university in Malaysia, we observed, in 2020, how the COVID-19 pandemic, changed our lives and the lives of our students. We would like to share our experiences in this commentary. It describes the contingency plans taken by the School of Medicine at International Medical University (IMU) to ensure that the delivery of the medical curriculum and its assessments has the best possible outcome in these tumultuous times, with plans to improve the delivery of teaching and learning, with an emphasis on technology-enhanced learning (TEL). We hope that this commentary is beneficial to those reading and that the contingency plans developed by IMU will help other institutions in the country and in this region navigate safely through the COVID-19 storm. © Malaysian Association of Education in Medicine and Health Sciences and Penerbit Universiti Sains Malaysia. 2023.
ABSTRACT
BACKGROUND: Healthcare workers treating SARS-CoV-2 patients are at risk of infection by respiratory exposure to patient-emitted, virus-laden aerosols. Source control devices such as ventilated patient isolation hoods have been shown to limit the dissemination of non-infectious airborne particles in laboratory tests, but data on their performance in mitigating the airborne transmission risk of infectious viruses are lacking. AIM: We used an infectious airborne virus to quantify the ability of a ventilated hood to reduce infectious virus exposure in indoor environments. METHODS: We nebulized 109 plaque forming units (pfu) of bacteriophage PhiX174 virus into a â¼30-m3 room when the hood was active or inactive. The airborne concentration of infectious virus was measured by BioSpot-VIVAS and settle plates using plaque assay quantification on the bacterial host Escherichia coli C. The airborne particle number concentration (PNC) was also monitored continuously using an optical particle sizer. FINDINGS: The median airborne viral concentration in the room reached 1.41 × 105 pfu/m3 with the hood inactive. When active, the hood reduced infectious virus concentration in air samples by 374-fold. The deposition of infectious virus on the surface of settle plates was reduced by 87-fold. This was associated with a 109-fold reduction in total airborne particle number escape rate. CONCLUSION: A personal ventilation hood significantly reduced airborne particle escape, considerably lowering infectious virus contamination in an indoor environment. Our findings support the further development of source control devices to mitigate nosocomial infection risk among healthcare workers exposed to airborne viruses in clinical settings.