Introduction:
The COVID-19 pandemic continues to pose a significant burden on healthcare systems around the world with successive waves and an increasing death toll despite progress in antiviral therapy and vaccine development[1] . More than 6 million COVID-19-related deaths have been reported globally as of July 2022 [2]. In Lebanon, more than 1 million confirmed COVID-19 cases along with more than 10,000 deaths have been reported so far [2-3].
Several factors are associated with an increased risk of COVID-19 progression to severe disease. Older age is a strong risk factor for poor outcomes[3-4]. The number of deaths, due to COVID-19 in the United States (U.S) in patients who are older than 65 years, was around 125 times higher than those aged between 18 and 29 years [4-5]. Similarly, in Lebanon, the reported number of deaths due to COVID-19 in patients older than 60 years was around 100 times higher than those aged between 20 and 29 years [6]. Other conditions associated with hospital admission, progression to critical illness, and mortality include cerebrovascular disease, chronic kidney disease (CKD), chronic lung disease, chronic liver disease, diabetes mellitus, cardiovascular conditions, autoimmune diseases, immunocompromising conditions, mental health disorders, obesity, and male gender [7]. Vaccination and herd immunity have contributed to decreasing the mortality associated with COVID-19 despite wide variations related to pre-existing co-morbidities and other risk factors [8] .
Monoclonal antibodies for COVID-19 are recommended either as post-exposure prophylaxis (PEP) for ambulatory patients with mild to moderate COVID-19 or pre-exposure prophylaxis for those who are at high risk for progression to severe disease [9]. They bind to virus spike protein and prevent the virus attachment to human cells , and mark the virus for elemination [10]. Sotrovimab is a recombinant human immunoglobulin G-1 (IgG1-Kappa) monoclonal antibody that binds to a conserved epitope on the spike protein receptor binding domain of SARS-CoV-2 and inhibits an undefined step that occurs after virus attachment and before the fusion of the viral and cell membranes [11].
In a phase 3 clinical trial, conducted in in four countries the United States, Canada, Brazil, and Spain between August 27, 2020 and March 4, 2021 [12] where the circulating COVID-19 variant was predominantly Delta variant in the US, Sotrovimab showed a significant reduction in the risk of COVID-19 progression among high-risk ambulatory patients with mild to moderate disease [12]. Patients who received Sotrovimab had 85% lower rates of hospitalization for > 24 hours for any cause or death at day 29 compared with the placebo arm [12]. Subsequently, Sotrovimab received emergency use authorization from the Food and Drug Administration (FDA) and preliminary approval from the European Medicine Agency (EMA) in May 2021 [11] . The American National Institute of Health (NIH) included IV Sotrovimab infusion as one of the therapeutic options recommended for outpatients with mild to moderate COVID-19 who are at high risk for disease progression [9]. More recently , with the rise and spread of the Omicron variant, it became obvious that Sotrovimab is not effective against it and its subvariants [13].
Real-life experience about the effectiveness of Sotrovimab is limited. In Lebanon, the COVID-19 response was particularly challenging as it happened amid an unprecedented economic crisis and political turmoil, aggravated by the catastrophic Beirut port explosion of August 4, 2020 [14]. All those factors added to the challenges of the pandemic, severely affected medical supplies and drug availability in the country, and resulted in critical shortages of various medications including essential COVID-19 therapies [14]. The American University of Beirut Medical Center (AUBMC) is a university tertiary care hospital in Beirut, Lebanon and was one of the tertiary medical centers who cared for a large number of COVID-19 patients. The hospital received donations of various drugs including 62 doses of Sotrovimab. In this study, we set to evaluate the efficacy of Sotrovimab in preventing COVID-19 hospitalizations and other patient-related outcomes, as well as its appropriateness of use at AUBMC.