Table 1.

Maximum observed SLC22A1 inhibition and calculated relative and absolute IC₅₀ values for darunavir, efavirenz, and control SLC22A1 inhibitor prazosin.

Inhibitor	TEA accumulation when 100 μM inhibitor used (%compared to inhibitor-free control)	Relative IC50 (μM)	Absolute IC50 (μM)
Prazosin	16.1	2.3	2.8
Darunavir	41.3	15.9	46.2
Efavirenz	39.7	7.4	21.8

The relative IC₅₀ is the amount of drug needed to achieve 50% SLC22A1 inhibition as determined from the maximum and minimum extremes of the non-linear regression plot. The absolute IC₅₀ is the amount of drug needed to achieve 50% SLC22A1 as determined from the maximum of the non-linear regression plot and 0% accumulation.