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

McCreary, Erin K; Pogue, Jason M

Because there are currently no efficacy data available for hydroxychloroquine in COVID-19, additional consideration should be given to the optimal dosing strategy. We use the following example to illustrate this point. If one were to consider these 2 compounds to be equally potent (identical EC 50 values) and utilize the PBPK data from Yao et al [18] , the 800 mg load, 400 mg daily regimen for hydroxychloroquine would yield R LTEC values of 2.76, 5.11, and 11.2 on day 1, 3, and 5, respectively. These R LTEC values would be slightly lower than those achieved with 500 mg by mouth twice daily of chloroquine on day 3 and significantly lower than those on day 5, suggesting the potential need for a higher dose to have similar activity. Although the 400 mg daily regimen is the most common regimen currently being assessed in clinical trials, the rationale for that dose is currently unclear, and at least 1 clinical trial in China is using a higher dose of 800 mg by mouth daily.