Insulin is only available as an injectable, or an inhaled form for now, but we are getting closer to having an oral dosage form available, the “holy grail” of diabetes treatment.
Insulin is a protein so the stomach digests it like it does other forms of protein, with acids and enzymes. Getting a sufficient amount into the bloodstream before it is destroyed is the challenge.
Novo Nordisk, a manufacturer of several other injectable insulin products, has developed, and demonstrated feasibility for an oral insulin dosage form. By adding sodium caprate (an FDA-approved food additive) to insulin tablets, they were able to improve the absorption of insulin and make it less susceptible to gastrointestinal degradation. In a small study of 50 patients, the oral insulin tablets had similar results to injected insulin.
While these results are encouraging, the company has decided not to continue to develop the product. The tablets required large doses to be effective and the large quantities needed to manufacture the product were not commercially viable.
Another drug manufacturer, Oramed, is developing an oral insulin product that is protected from degradation in the stomach and is absorbed in the intestine, where it travels directly to the liver. This may result in less weight gain and hypoglycemia than is seen with injectable insulins. Clinical trials of this product have been encouraging. More information is available here .
Insulin therapy is often delayed by patients due to fear of injections, and misconceptions about insulin. Making insulin more acceptable to patients and more convenient to use will help get them on the right therapy at the right time and could be a potential game changer in the fight against diabetes.