Figure 4.

Comparison of EC₅₀ values. (a) Comparison of percentage of viral inhibition for hydroxychloroquine (HCQ) by data source, including digitized 48‐hour in vitro data (green), 24‐hour in vitro data (orange) obtained from Yao et al., ³ in vitro data from Liu et al. ⁹ and Touret et al., ¹⁰ and longitudinal clinical data (blue; solid line = available data; dashed line = extrapolated data. Raw data and curves from Yao et al. ³ were digitized and displayed directly in the plot. The model used for these data is shown in the original manuscript and used a sigmoidal concentration‐response function $Y=\text{Bottom}+\frac{\text{Top}-\text{Bottom}}{1+{10}^{\left(\text{LogEC}50-X\right)\times \text{HillSlope}}}$. For the recently added references (Liu et al. ⁹ and Touret et al. ¹⁰ ), a Hill coefficient equal to 1 was assumed, and the different points for plotting purposes were calculated from the half‐maximal effective concentration (EC₅₀) values provided in the original manuscripts. (b) Table including the EC₅₀ values and in vitro experimental conditions from Yao et al., Liu et al., and Touret et al. ³ , ⁹ , ¹⁰ *Adjusted EC₅₀ was calculated to obtain the total drug value as follows: $\text{total}\text{drug}=\frac{\text{free}\text{drug}}{f_u}$, where fu = 0.5.