PSC833 - Specific MDR1/P-gp Inhibitor
|Product||Transporter||Technology||Probe Substrate||Reference Inhibitor||Barrier|
|SB PSC 833 50 μg/1 mg/5 mg||MDR1/P-gp
PSC 833 (valspodar, Amdray), a non-immunosuppressive cyclosporine D analog, is a 2nd generation ABCB1/P-gp/MDR1 specific reversal agent.
Clinical development of P-gp reversal compounds has not been successful mostly due to a variety of toxicities (e.g. myelotoxicity, emesis, ataxia) and pharmacokinetic interactions. However, partial successes have been documented such as an increase in overall survival of patients with AML treated with cytarabine, daunorubicin, etoposide with and without PSC 833 (1.8 elimination of new drugs and/or their metabolites vs. 1.3 years, p50.03) [Kolitz JE et al., in Am. Soc. of Hematology. Orlando, FL, 2001].
PSC 833 is a useful reagent to selectively block P-gp in different assay systems. The fact that a broad set of preclinical and clinical data is available for this compound (reviewed in Tai 2000 Curr Opin Mol Ther 2:459) makes it especially valuable for in vitro and in vivo ADME studies.
Learn more about PSC833 (valspodar, Amray).