AREB members did acknowledge the promising results of a new intradermal (ID) PEP regimen, “one week, 4-site”, developed by the Thai Red Cross and the Queen Saovabha Memorial Hospital in Bangkok, Thailand; it can be completed within one week (4-site ID injections on days 0, 3, and 7). One study investigating this protocol reported the geometric mean titre of rabies neutralizing antibodies on days 14 and 28 as being

significantly higher than with the WHO approved and widely used updated Thai Red Cross (TRC) regimen (2-site ID injections on each of days 0, 3 and 7, and 28). AREB members recognized that reducing the number of clinic visits and shortening the time to complete the PEP vaccination schedule would not only reduce SCH772984 solubility dmso costs for the patient

but might also help increase compliance with the complete course of PEP. It was recommended that the results be validated by another clinical trial using the same 1-week, 4-site PEP regimen in an independent centre before this regimen becomes an acceptable recommendation. Intradermal (ID) rabies vaccination has been utilized in Thailand since it was approved in 1988. A comparison was presented of the different mechanisms involved in the immune response after ID or intramuscular (IM) vaccination. ID vaccine administration delivers antigen to a compartment rich in dendritic cells, i.e. antigen-presenting cells. They capture the antigen and migrate to the draining lymph nodes, where T and B cells are triggered into action. A comparison of cytokine see more expression after IM

or ID vaccination, using a cytokine antibody microarray, showed that ID vaccination induces significant levels of IL-5, IL-6, indicating that the ID regimen induces a Th2 immune response, i.e. a preferential production of antibodies. IM vaccination Adenylyl cyclase induces higher levels of TNF-alpha, IFN-gamma and GM-CSF and favors a Th1 response, i.e. cell-mediated immunity. Such mechanisms could explain why a lower dose of rabies antigen is effective when vaccinating by the ID route compared to the IM route. AREB members stressed the necessity of ensuring that each patient receives at least the minimum amount of antigen required to induce an adequate immune response, independently of the type of modern rabies vaccine used and the volume of diluent used to reconstitute it. They noted that this approach is taken for other vaccines used to protect human health. They thus consider that the ID dose must be pharmaceutically defined by its potency (IU/ID dose), and not only by its volume, which is currently the recommendation in international guidelines. This requires defining a standardized and reproducible measure of the potency, as recommended by biological standardization committees.