Published time: 15 April 2020
Authors: Fabio S Taccone, Julie Gorham, Jean-Louis Vincent
Keywords: Covid-19, Hydroxychloroquine, respiratory
With the rapid spread of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), critical care physicians are seeing increasing numbers of patients with acute respiratory failure secondary to coronavirus disease 2019 (COVID-19) and reporting mortality rates of 40–65% for those requiring mechanical ventilation1 —strikingly higher than the mortality rates reported for the more typical acute respiratory distress syndrome associated with other diseases.2 The focus of therapeutic intervention has therefore been not only to reverse hypoxaemia and provide adequate organ support, but also to decrease viral load and thus limit disease severity. In addition to several antiviral agents, antimalarial drugs have been proposed as treatments that could reduce transmission of the virus. In-vitro studies have shown that chloroquine and hydroxychloroquine can both inhibit SARS-CoV-2 transmission,3–5 through alkalinisation of the intracellular phagolysosome, which prevents virion fusion and uncoating and, therefore, viral spread. Early results from clinical studies conducted in China suggest that chloroquine use might have been associated with reduced fever, increased resolution of lung lesions on CT, and delayed disease progression.6,7 Results of two French studies suggested that hydroxychloroquine could reduce the viral load in patients with COVID-19— in particular, if combined with azithromycin8,9 (table). On the basis of these preliminary findings, chloroquine and hydroxychloroquine have been prescribed to patients to reduce the length of hospital stay and improve the evolution of COVID-19-related pneumonia. Nevertheless, the recently published Surviving Sepsis Campaign guidelines on the management of critically ill patients with COVID-19 concluded that there was insufficient evidence to offer any recommendation on the routine use of these drugs in patients admitted to the intensive care unit (ICU).10 How can we explain these discrepancies and how should antimalarial drugs be used in the clinical management of patients in the ICU with severe COVID-19?