Monoclonal antibodies (mAbs) have been known since the 1970s. However, their therapeutic potential in the medical field has recently emerged, with the advancement of manufacturing techniques. Initially exploited mainly in the oncology field, mAbs have become increasingly relevant in Infectious Diseases. Numerous mAbs have been developed against SARS-CoV 2 and have proven their effectiveness, especially in the management of the mild-to-moderate disease. In this review, we describe the monoclonal antibodies currently authorized for the treatment of the coronavirus disease 19 (COVID-19) and offer an insight into the clinical trials that led to their approval. We discuss the mechanisms of action and methods of administration as well as the prophylactic and therapeutic labelled indications (both in outpatient and hospital settings). Furthermore, we address the critical issues regarding mAbs, focusing on their effectiveness against the variants of concern (VoC) and their role now that a large part of the population has been vaccinated. The purpose is to offer the clinician an up-to-date overview of a therapeutic tool that could prove decisive in treating patients at high risk of progression to severe disease.

Objectives: The aim of the study was to identify variables that can influence atazanavir plasma concentration. Methods: We retrospectively analysed atazanavir trough concentration of HIV infected patients who performed therapeutic drug monitoring between October 2007 and July 2011. Qualitative variables were compared with X² test while continuous ones with Mann-Whitney and Student’s t-test. A linear regression model was used to investigate factors influencing atazanavir plasma concentration. Therefore, we analysed the impact of cirrhosis on atazanavir pharmacokinetic variability. Results: 255 plasma samples from 179 patients were analysed. At the univariate analysis female gender (+144.4 ng/mL; p=0.05) and tenofovir (+196.8 ng/mL; p=0.002) were associated with higher atazanavir concentrations. The multivariate model confirmed these two variables (+164.6 ng/mL; p=0.02 and +150.4 ng/mL; p=0.01) as independently associated with higher atazanavir trough concentration. The analysis of cirrhotic population showed an influence of tenofovir (-255.9 ng/mL; p=0.01), increased AST (+95.3 ng/mL; p=0.09), ALT (+67.9 ng/mL; p=0.07) and creatinine (+517.2 ng/mL; p=0.04). The multivariate model confirm that tenofovir was associated with lower atazanavir trough concentration (-284.1 ng/mL; p=0.005) while AST values significantly increased atazanavir concentrations (+114.5 ng/mL; p=0.03). Discussion: Atazanavir is a safe and manageable drug. Our results suggest that female patients tend to have higher atazanavir plasma concentration, while the effect of tenofovir needs to be better clarified.

HIV infection leads to a faster progression of liver disease in subjects infected with HCV, as compared with HCV mono-infected patients. Previous reports suggest that sustained virological response (SVR) rates are lower in HIV/HCV coinfection than in HCV monoinfection. We aimed to compare SVR rates of these two populations.

Coronavirus disease 19 (COVID-19) continues to spread worldwide as a severe pandemic. The Omicron BA.2 became the predominant variant and the protagonist of the ongoing surge. As the virus continues to mutate, using of approved drugs or developing new therapeutic or prophylactic therapies against COVID-19 could be more complex. Sotrovimab is a monoclonal antibody (mAb) targeting the conserved epitope on the spike protein receptor; the most recent studies observed that it has substantially decreased in vitro activity against the Omicron BA.2 subvariant, but real-life data are still scarce. We describe the outcome of a case series of outpatients with BA.1 or BA.2 infection treated with sotrovimab. We conducted a retrospective observational study including all non-hospitalized adult patients treated with sotrovimab, for which a Sanger sequencing of SARS-CoV-2 was performed within a regional genomic surveillance program. Eleven (50%) patients with BA.1 infection and eleven (50%) with BA.2 infection were considered. Most patients were immunocompromised. During the follow-up period, no patient died and only one with BA.1 infection was hospitalized for severe COVID-19 pneumonia onset. One month after treatment, 90.9% of patients were completely asymptomatic in each group. We demonstrated that patients carrying the BA.2 variant treated with sotrovimab did not evolve to severe COVID-19, showing a similar outcome to BA.1 infected patients. Further studies are needed to prove that vaccination or the presumably high doses of mAbs used can protect this group of patients at high risk of progression.