Coronavirus, uses the Angiotensin Converting Enzyme-2 Receptor to enter airway cells. Viral endocytosis is mediated by several factors, including clathrin, the adaptor protein-2 complex (AP2) and the adaptor-associated kinase-1 (AAK1). 2 According to a recent report, 3 COVID-19, the disease caused by SARS-CoV-2, is characterized by three clinical patterns: no symptoms, mild to moderate disease, severe pneumonia requiring admission to Intensive Care Unit (ICU) in up to 31% of the patients. 3 Thus far, there is no specific therapy for COVID-19 infection. No benefit of lopinavir-ritonavir treatment resulted in a recent trial. 4 Hydroxychloroquine, currently used in view of its "in vitro" observed effect of reduction of viral replication, seems unsatisfactory. 5 Elevated proinflammatory cytokine/chemokine responses seem associated with respiratory failure. 3 Recently, tocilizumab, an interleukin-6 inhibitor, was reported as effective in patients with severe COVID-19 pneumonia. 6 Baricitinib, another inhibitor of cytokine-release, seems an interesting anti-inflammatory drug. It is a Janus kinase inhibitor (anti-JAK) licensed for the treatment of rheumatoid arthritis (RA) with good efficacy and safety records. 7 Moreover it seems to have anti-viral effects by its affinity for AP2-associated protein AAK1, reducing SARS-CoV-2 endocytosis. 8 On this basis, we assessed the safety of baricitinib therapy combined with lopinavir-ritonavir in moderate COVID-19 pneumonia patients and we evaluated its clinical impact. All consecutive hospitalized patients (March 16th −30th) with moderate COVID-19 pneumonia, older than 18 years, were treated for 2 weeks with baricitinib tablets 4 mg/day added to ritonavir-lopinavir therapy. The last consecutive patients with moderate COVID-19 pneumonia receiving standard of care therapy (lopinavir/ritonavir tablets 250 mg/bid and hydroxychloroquine 400 mg/day/orally for 2 weeks) admitted before the date of the first baricitinib-treated patient served as controls. Antibiotics were scheduled only in the case of suspected bacterial infection. Inclusion criteria were: a. SARS-Co-V2 positivity in the nasal/oral swabs; b. presence of at least 3 of the following symptoms: fever, cough, myalgia, fatigue; c. evidence of radiological pneumonia. After discharge, patients treated with baricitinib were planned to be followed for additional 6 weeks. Exclusion criteria: history of thrombophlebitis (TP), latent tuberculosis infection (QuantiFERON Plus-test positivity, Qiagen, Germany 9), pregnancy and lactation. Mild to moderate COVID-19 disease definition: presence of bilateral pneumonia with or without ground glass opacity and in absence of consolidation, not requiring intubation at enrollment; arterial oxygen saturation (SpO2) > 92% at room-air, and ratio arterial oxygen partial pressure/fractional inspired oxygen (PaO2/FiO2) 10 0-30 0 mmHg. Parameters daily accessed were: fever, pulmonary function, Modified Early Warning Score (MEWS), 10 pulse rate, blood pressure. After the initial execution, radiology imag...
