Proteins and therapeutic peptides such as insulin, growth hormone, antibodies and enzymes, have been routinely used for therapeutic purposes for almost 70 years. Despite major advances in manufacturing methods and cleaning of protein, methods of administering the protein to patients have remained unchanged and are based solely on subcutaneous injections of the native protein (be it with a regular syringe, “pen” syringe or “pump”). Subcutaneous injections may be expeditious and accurate but are less preferable in terms of patient treatment compliance due to the burden of daily or even several times a day (e.g. for diabetes) injection, and due to the accompanying pain and potential for developing localized inflammation, as well as the awkwardness involved in administering or transport the medication.

There have been numerous unsuccessful attempts by academia and the pharmaceutical industry to develop oral protein vaccines. A typical approach is to “pack” the native protein in micro or nano particles (liposomes, microspheres, etc.) and add it the formulation molecules that direct it to the intestine; and in many instances to also add penetration enhancers, additives which interfere with the tight nodes in the intestine lining and consequently facilitate proteins in entering the blood. The current approach is to keep the protein protected from the digestive elements in the gastrointestinal tract. However, none of the tests have thus far received FDA approval and managed to penetrate the protein into the blood safely and efficiently.

A new strategy developed in our laboratories (the laboratory of Prof. Ramona Margalit, Tel Aviv University and the laboratory of Dr. Yaron Dekel, Shamir Research Institute) has been published in several scientific publications and has been registered and approved for patent at the US and European Patent Offices, based on arranged and reversible aggregates of the protein – protein fibers. These aggregates are formed in acidic pH and have shown resilience in SIF and GIF tests that replicate an acidic and proteolytic environment in the gastrointestinal tract. They also showed in-vivo the ability of insulin fiber to lower blood glucose levels of diabetic mice. While insulin is a small peptide, we extended the repertoire of the protein to that of proteins of high molecular weight (monoclonal antibodies such as Herceptin and multiclonal such as IgY), that can create stable multimeric proteins and to break them down to active monomeric proteins without damaging the ability of the connection of the antibody to the active ligand. This illustrated that fibers or reversible multimeric proteins of protein medications can be used as a time release buffer for active proteins to protect the monomeric proteins from the gastrointestinal environment and consequently extend the shelf life of the vaccine.

The traditional demand for growth hormone treatment increases together with newer use of the protein as an “aging tracker.” Consequently, we selected the growth hormone molecule for further experimentation. Growth delays among children require daily injections for a number of years. If those children could receive a pill or syrup instead, it would significantly improve their quality of life. Of course, if the formulation is successful, it could be easily replicated for other pharmaceutical proteins. In this project, we intend to produce fibrous ingredients of growth hormone together with molecules that activate the Endocannabinoid System in the intestine in order to increase the absorption in the intestine. The combination of the Endocannabinoid System in providing oral protein absorption is groundbreaking and could result in the pioneering of additional pharmaceutical proteins, thereby creating a technological platform for administering protein orally in hundreds of other diseases.

Sources:

Scientific Publications:

[1]    Y. Dekel, Y. Glucksam, I. Elron-Gross, R. Margalit, Insights into modeling streptozotocin-induced diabetes in ICR mice., Lab Anim. (NY). 38 (2009) 55–60. doi:10.1038/laban0209-55.

[2]    Y. Dekel, Y. Glucksam, R. Margalit, Novel fibrillar insulin formulations for oral administration: Formulation and in vivo studies in diabetic mice, J. Control. Release. 143 (2010) 128–135. doi:10.1016/j.jconrel.2009.12.018.

[3]    Y. Dekel, Y. Machluf, T. Gefen, G. Eidelshtein, A. Kotlyar, Y. Bram, et al., Formation of multimeric antibodies for self-delivery of active monomers, Drug Deliv. 24 (2017) 199-208. doi:http://dx.doi.org/10.1080/10717544.2016.1242179.

 

Patents:

[1] Dekel Y, Margalit R (2014) System for delivery of protein in insoluble fibrillar or aggregate form. US patent # 8,632,802

[2] Dekel Y. Margalit R. (2015) System for delivery of protein in insoluble fibrillar or aggregate form. European patent application 09715885.1. 2259775