+1 (629)348-3199Research Article - International Journal of Respiratory Medicine (2023) Volume 8, Issue 2
Pre-exposure treatment and prevention of SARS-COV-2
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a severe pneumonia caused by an enveloped, single-stranded beta coronavirus, belonging to the coronaviridae family. SARSCoV-2 (Covid-19) has caused several pandemic due to its ability to mutate into new subvariants of variable virulence. According to the latest report by the World Health Organization, Covid-19 has infected 664, 097, 132 cumulative cases and caused more than 6, 716, 108 deaths since the first pandemic in Wuhan, China. Covid-19 has paralyzed businesses and has been an economic burden in many countries globally due. Vaccination has been very effective in preventing Covid-19 infections. However, some individuals with immunosuppression are unable to mount adequate immunity after vaccination and others are allergic to the components of the Covid-19 mRNA vaccines. These individuals require pre-exposure prophylaxis in order to prevent them from developing SARS-CoV-2 infection and progressing to severe disease leading to death. Tixagevimab plus cilgavimab (Evusheld) are IgG1 long-acting recombinant human monoclonal antibodies (mAbs), produced using recombinant DNA technology. Both biologics bind to nonoverlapping epitopes of the spike protein receptor-binding domain (RBD) of SARS-CoV-2 spike protein. They block the spike protein from attaching to its cognitive receptor the angiotensinconverting enzyme 2 (ACE2) receptor. Clinical trials have shown that evusheld treatment when administered to individuals who are at risk of Covid-19 infection, leading to severe disease result in 77% reduction in the risk of developing SARS-CoV-2. Tixagevimab plus cilgavimab pre-exposure prophylaxis is approved by the Medicines and Healthcare products Regulatory Agency in Great Britain and by the European Union. However, it is unlikely to neutralize some of the subvariants of Omicron, such as Omicron XXB.1.5 (‘Kraken’). Therefore, pre-exposure treatment of Covid-19 with evusheld should be administered cautiously in countries where Omicron subvariants are endemic. Noteworthy. Pre-exposure prophylaxis should not be a substitute for the two doses of Covid-19 vaccination.
Author(s): Nightingale Syabbalo