Chloroquine, hydroxychloroquine and azithromycin block hERG at physiological temperatures
The potency of each compound for hERG block was determined using a Syncropatch PE384 automated patch clamp system. Typical current traces and timecourse of block for ~IC50 doses of chloroquine (1 µM), hydroxychloroquine (3 µM) and azithromycin (100 µM) are shown in Figures 1A-C. The potency of hERG inhibition (IC50 ± SEM) was 1.47±0.07 µM, 3.78±0.18 µM, and 280.1±14.7 µM for chloroquine, hydroxychloroquine and azithromycin respectively (Figure 1D).