OY-101, an orally active compound, serves as a potent and specific inhibitor of P-glycoprotein (P-gp). It has the capability to sensitize drug-resistant tumors and counteract tumor multidrug resistance efficiently. Compared to Tetrandrine [1], OY-101 demonstrates enhanced water-solubility, cytotoxicity, and reversal activity.

OY-101 exhibits a remarkable synergistic anticancer effect with Vincristine in multidrug-resistant Eca109/VCR cells, with an IC50 of 9.9 ± 1.3 nM[1]. OY-101 (0-5 μM) demonstrates negligible toxicity to Eca109/VCR cells and significantly enhances Vincristine sensitivity within these cells[1].

OY-101, administered at a dose of 30 mg/kg every other day via oral gavage for a duration of three weeks, was observed to enhance the sensitization to vincristine in vivo without apparent toxicity [1]. Additionally, OY-101 demonstrated favorable pharmacokinetics with both intravenous administration (3 mg/kg) and oral administration (30 mg/kg) in single doses [1].