[CAS NO. 128446-35-5]  (2-Hydroxypropyl)-β-cyclodextrin (HP-β-CD)

HP-β-CD, due to its excellent biocompatibility, has been widely used in drug delivery systems, environmental remediation, food additives, and pharmacotherapy. HP-β-CD can readily cross the BBB and target nerve cells. HP-β-CD is well tolerated in the animal species tested (rats, mice and dogs), particularly when dosed orally, and shows only limited toxicity. After a single 200 mg/kg intravenous dose in rats and dogs, 14C-HP-β-CD was eliminated rapidly (more than 90% in 4 h), almost completely as the intact compound and mostly by renal excretion. The excretion in faeces and expired air was minimal. The plasma elimination half-life was 0.4 h in rats and 0.8 h in dogs. After oral administration of HP-β-CD in both rats and dogs, 86% was excreted via the faeces in both species, where as less than 5% was excreted in the urine. The absolute bioavailability was estimated at 3.3% in the dog and less in the rat. In both rats and dogs following intravenous administration, tissue distribution was limited: in rats the highest concentration was found in the kidney and lung and in dogs, the highest concentrations were in the kidney and the liver. Plasma levels of unchanged HP-β-CD declined rapidly and showed a bi-phasic decline after single intravenous and oral dosing in healthy volunteers. The utility of a 45%w/v HP-β-CD aqueous dosing vehicle in preclinical studies is very common. This vehicle is useful with poorly aqueous drugs.