Conversely, we know that pharmacological interferences occurs between the antiviral drugs used to treat SARS-CoV-2 and calcineurin inhibitors [16]. The main issue of drug–drug interactions is an increased in immunosuppressant plasma concentrations due to their shared metabolism via cytochrome-P450-3A4. In particular, the interaction between lopinavir and calcineurin inhibitors has already been characterized as being based on suppression of cytochrome-P450-3A4. In contrast, the interaction between hydroxychloroquine and calcineurin inhibitors is less clear. Its metabolism via cytochrome-P450-3A4, as well as via cytochrome-P450-2C8, might theoretically increase the plasma concentration of the immunosuppressant. Consequently, close monitoring of immunosuppressant levels is warranted.