Encequidar, also known as HM-30181, is an oral P-glycoprotein (P-gp) inhibitor developed to enhance the oral bioavailability of P-gp substrate drugs. Encequidar showed the highest potency (IC(50)=0.63nM) among several MDR1 inhibitors, including cycloporin A, XR9576, and GF120918, and effectively blocked transepithelial transport of paclitaxel in MDCK monolayers (IC(50)=35.4nM). Encequidar is currently under clinical trials.

GP(33-41) TFA, a 9-amino-acid (aa) peptide, represents the optimal sequence of the lymphocytic choriomeningitis virus GP1 epitope, effectively upregulating H-2D b molecules on the RMA-S (Db Kb) cell surface with a SC 50 value of 344 nM [1].

P-gp inhibitor 4 is a selective P-glycoprotein modulator with an EC 50 of 94 nM. P-gp inhibitor 4 increases drug transport across gastro-intestinal barrier and recovers doxorubicin toxicity in multidrug resistant cancer cells .