elacridar

Elacridar, also known as GF120918, is a potent dual inhibitor of the efflux transport proteins P-glycoprotein (ABCB1) and breast cancer resistance protein (ABCG2). It is used primarily in pharmacological research to increase the oral absorption and central nervous system penetration of co-administered drugs by blocking transporter-mediated efflux at intestinal and blood-brain barrier surfaces.

By inhibiting ABC transporters, elacridar reduces the active efflux of substrate drugs, thereby elevating systemic exposure and tissue concentrations. It is active at low concentrations in vitro and has been shown to increase brain and tumor concentrations of various chemotherapeutic agents in animal models. It generally does not possess strong intrinsic anticancer activity.

Elacridar has been studied in preclinical and early clinical contexts as a means to overcome multidrug resistance in cancer and to improve CNS drug delivery. It has been evaluated in combination with agents such as paclitaxel, docetaxel, and topotecan to assess pharmacokinetic interactions and potential therapeutic benefit. It is not approved as an anticancer drug.

Pharmacokinetics and safety considerations include variable oral bioavailability and the potential for altered pharmacokinetics of co-administered substrates due to transporter inhibition. Because it changes exposure and tissue distribution, elacridar can influence toxicity profiles observed with partner drugs. Safety findings come from early-phase studies and preclinical work.

Historically, elacridar was developed by Pfizer and was initially designated GF120918. It has been the subject of extensive research in the 1990s–2000s as a means to address drug resistance and enhance CNS and tumor drug delivery, rather than as a stand-alone therapy.