BioSante Pharmaceuticals, Inc. has announced the publication of positive results of a preclinical study of its proprietary calcium phosphate nanoparticle (CAP) delivery system for the oral delivery of insulin in the June 11 issue of the peer-reviewed International Journal of Pharmaceutics. An abstract of the study is available on the journal's Web site.
"The results of this study add to the mounting evidence that our unique technology may represent a major advance in the development of an easy, pain-free alternative to currently injected products such as insulin for diabetics, allowing them to live a more comfortable life," said Dr. Tulin Morcol, associate director of drug delivery and related technologies for BioSante. "The study results show that our CAP formulation has the potential to overcome the considerable obstacles to effective oral delivery of insulin and other currently injected therapeutic proteins."
The published study evaluated the use of BioSante's BioOral(TM) drug delivery system to administer insulin orally. The oral formulation was developed by aggregating caseins (the principle protein in milk) around a proprietary formulation of CAP, polyethylene glycol (PEG, a polymer) and insulin by scientists at BioSante's research center in Smyrna, Georgia. The therapeutic efficacy of the formulation, known as CAPIC(TM), was tested in diabetic mice that were either fasted or fed prior to the experiments.
A single dose of CAPIC was administered via the oral route into the stomachs of the mice, while control groups were given insulin alone, either by subcutaneous injection or via the oral route into the stomach. Blood glucose levels were then monitored every one to two hours for 12 hours.
CAPIC reduced the blood glucose levels of fasted diabetic mice by 80 percent within the first hour and maintained the reduction for 12 hours. In contrast, insulin alone (without CAP) only reduced blood glucose about 20 percent and only for four to five hours. The glucose-reducing effect of CAPIC was comparable to the levels in the subcutaneously injected controls; however, CAPIC reduced glucose for 12 hours versus only about five hours for insulin alone.
In fed mice, CAPIC induced a 50 percent reduction of blood glucose levels within three hours, and glucose returned to previous levels after five hours. In contrast, an identical dose of insulin alone had no effect on glucose levels in fed mice controls. These important results suggest that there may also be a postprandial application for CAPIC.
"The acidic environment of the stomach would normally break down native insulin before it can be absorbed into the bloodstream," said Dr. Morcol. "Our proprietary formulation, with the casein coating around the CAP-insulin core, appears to protect the insulin as it passes through the stomach to reach the small intestines intact and in a functionally active form."
Dr. Morcol added that the study results as well as other studies using CAP indicate that CAP also could be used to preserve the functional ability of other therapeutic proteins or peptides for oral administration.
"The results of this study further strengthen our belief that the use of CAP offers great potential to become an important new treatment option for diabetics and others who currently use injectable therapies," said Stephen M. Simes, president and chief executive officer of BioSante. "We plan to conduct further studies internally as well as to continue our work with other companies with insulin and other protein and peptide formulations."
BioOral is an oral delivery system using BioSante's CAP nanotechnology -- microscopic particles of calcium phosphate similar to that found in teeth and bones. The patented formulation is nontoxic and biodegradable, offering a multitude of potential medical applications.