Coronavirus Disease 2019 Treatment: A Review of Early and Emerging Options

McCreary, Erin K; Pogue, Jason M

Chloroquine, an antimalarial agent with anti-inflammatory and immunomodulatory activities, has gained significant interest as a potential therapeutic option for the management of COVID-19. In early February, Wang et al [3] demonstrated potent in vitro activity of chloroquine against SARS-CoV-2 with an EC 50 at 48 hours of 1.13 µM in Vero E6 cells. These data were consistent with previous data for chloroquine's inhibitory activity against SARS-CoV-1 and MERS-CoV in various cell lines, where EC 50 values of 1-8.8 and 3.0 µM were demonstrated, respectively [15] . These findings have supported the clinical use of chloroquine, at a dose of 500 mg by mouth twice daily, in numerous clinical trials in China during this outbreak. Although the rationale for this dosing regimen remains unclear, and peer reviewed data from the trials are currently unavailable, it was announced in mid-February that promising early results have been demonstrated. Per Gao et al [16] , "thus far, results from more than 100 patients have demonstrated that chloroquine phosphate is superior to the control treatment in inhibiting the exacerbation of pneumonia, improving lung imaging findings, promoting a virus-negative conversion, and shortening the disease course according to the news briefing. Severe adverse reactions to chloroquine phosphate were not noted in the aforementioned patients. "