Inhibition of novel ß coronavirus replication by a combination of interferon-a2b and ribavirin

Falzarano, Darryl; de Wit, Emmie; Martellaro, Cynthia; Callison, Julie; Munster, Vincent J.; Feldmann, Heinz

During the outbreak of SARS-CoV, different combinations of therapeutic interventions were attempted; however, none were implemented in a manner that allowed a critical assessment of their effectiveness. The most frequently administered therapeutics were broad-spectrum antibiotics, glucocorticoids and ribavirin [37] [38] [39] . The lack of a standard dosing regimen for ribavirin makes comparisons difficult 18 ; however, low dose ribavirin (400-600 mg/day) therapy was shown to be ineffective likely due to an insufficient plasma concentration 40 . In contrast, when used at higher doses other studies have found that ribavirin alone reduced viral loads in over half of the patients and when combined with the viral protease inhibitors lopinavir/ritonavir, patients had a lower incidence of adverse outcomes 16 unclear whether ribavirin alone was effective against SARS-CoV 41 . Alfacon-1, a synthetic IFN-a, has also been suggested to be beneficial to patients 17 . Unfortunately, all of these studies suffer from the confounding use of corticosteroids in doses that vary among studies making a definitive treatment elusive. It has been suggested that combination of interferon and ribavirin treatment should be evaluated 18 . While ribavirin can result in reversible hemolytic anemia, this complication typically occurs following longer treatment protocols 35, 42 . This suggests that short-course ribavirin therapy for an acute infection such as nCoV may not be a significant complication as mild anemia was the most frequently reported side effect during ribavirin treatment for Lassa virus infection 43 .