Eithan Galun, MD, The Goldyne Savad Institute of Gene Therapy, Hadassah University Hospital.
Background
Current interest in vaccination technology revolves around the prospect of “biopharming,” or the expanding technologies stemming from agricultural biotechnology. Initial products have focused mainly on strengthening crops by developing their own biopesticides as well as enhancing environmentally friendly herbicides. As the field advances, the use of transgenic plants for production of oral vaccines is becoming more prevalent.
Vaccinations are, in theory, the simplest prevention to a variety of viral diseases. However, in reality, the use of injectable vaccines is not only costly, but stressful to both the recipient as well as the administrator. In many thirdworld countries, vaccinations are too expensive to properly inoculate the population against such controllable diseases as diptheria, measles and tetanus. The prospect of producing a readily available, low-cost vaccine for immunization against wide-spread, yet containable diseases is clearly beneficial and highly desirable.
An effective vaccine at low cost production is the only foreseeable solution for numerous worldwide human pathogens, including AIDs, malaria, tuberculosis, rotavirus infection and many more. Many problems with injectable vaccines, such as high cost, high maintenance (e.g., refrigeration), and sterility of needles, demands further advances in vaccination technology to overcome these hurdles.
Market
Given the financial aspect of current vaccination programs in under-developed countries, there is a drastic need for lowering the burden of maintaining basic public health. Vaccinations are the simplest method to achieve this goal, and the climate indicates that it is also the most prosperous. The global vaccine market has on average grown by about 10% each year over the past decade or so. A report by Mercer Management Consultants shows a growth from $2.9 billion in 1992 to $6 billion in 2002. This does not take into consideration the advancement of plant-derived oral vaccines.
Some estimates indicate an expected growth for agricultural biotechnology products to reach $20-25 billion by 2010.
The Innovation
We have developed a new method of vaccine development through the production of viral like particles in edible crops. The co-expression of viral structural proteins should enhance the proper presentation of viral related antigens to the human immune system. The hepatitis A virus (HAV) has been chosen as the target proof-of-concept model, where vaccination with isolated capsid proteins failed because neutralizing antibodies recognize specific structures on the viral particle, which are created only after the assembly of the capsid.
Using this technology, transgenic tomato plants have been developed that express HAV antigens.
R&D Program
HAV was chosen as a proof of concept model since neutralizing antibodies recognize specific structures on the viral particle that is created only after the assembly of the capsid, thereby causing vaccination with isolated capsid proteins to fail. Transgenic tomato plants expressing HAV antigens have been developed for preclinical testing. A second generation of tomatoes is currently being developed to express higher levels of HAV proteins for the induction of a protective immune response. In addition, a vaccination for hepatitis C virus using the same method is also being developed.
The subsequent R&D program will be based on the following:
- Continued development of high producers of HAV Tg tomatoes
- Continued development of a preclinical study program in rodents and in non-human primates
- Development of clinical studies Contact
Contact
Yuval Kupitz,
Business Development, Pharmaceuticals
Tel: +972-2-6778364
Email: yuvalk@hadasit.co.il
