Background: Pirarubicin (THP), an analogue of doxorubicin, has exhibited promising activities against acute leukemia, malignant lymphoma, and several solid tumors. However, the cumulative cardiotoxicity limits its wide application in chemotherapy.
Method: To provide an alternative strategy for reducing the cardiotoxicity, a novel THP liposome powder (L-THP), comprising distearoylphosphatidylcholine, distearoylphosphatidylglycerol, cholesterol, and lactose was appropriately prepared based on the physicochemical properties of THP. And L-THP was characterized and evaluated. Comparative studies on pharmacokinetic and biodistribution behaviors between L-THP and commercialized THP injection were performed in normal mice through intravenous administration.
Results: When L-THP was reconstituted in a proper amount of normal saline for injection, it had a mean diameter of around 220.0 nm, a zeta potential of about -33.0 mV, and a high THP entrapment efficiency of more than 93.1%. Pharmacokinetics study showed that heart accumulation of THP could be reduced by 81.2% for L-THP.
Conclusion: These results suggest that our L-THP might greatly reduce the cardiotoxicity, thus improving the therapeutic index of THP. Meanwhile, further preclinical studies are warranted to define the cardiotoxicity and the therapeutic efficacy of L-THP.