Liposome-entrapped calcitonin and parathyroid hormone are orally effective in rats.

We have demonstrated that liposomally entrapped calcitonin (CT) and parathyroid hormone (PTH) can be orally effective in regulating blood calcium. Liposomal CT produced hypocalcemia and liposomal PTH produced hypercalcemia upon oral administration to rats. Specific liposomal formulations were necessary to affect the appropriate decrease and increase in blood calcium concentration. Future extension of these studies may lead to clinically valuable forms of liposomal-peptide preparations.