Epicutaneous allergen-specific immunotherapy: time for revival?
Published Online: October 14, 2011
Immunization via the skin is an ancient technique and also the first vaccine, introduced by Edward Jenner, was applied to scarified skin. The first reports on allergen-specific immunotherapy administered via skin date back to Besredka in 1917 and then Patrizel and Blamoutier in the 1950s, but after that this route was nearly forgotten. The epidermis, however, may represent the ideal route for allergen administration. It has a high density of potent professional antigen-presenting Langerhans cells, which should enhance efficacy. Also, the epidermis is not vascularized, thus reducing the risk for allergen accidentally reaching the circulation, which should enhance safety. Finally, allergen administration to the epidermis can be performed without needles and therefore could be self administered by patients, which should enhance convenience and compliance.
In a Research Article in The Journal of Allergy & Clinical Immunology (JACI), Senti et al. present a placebo controlled double blind dose escalation study in 132 patients suffering from grass pollen induced rhinoconjunctivitis. Patients were randomly allocated to one of four treatment groups (placebo, 10HEP, 50HEP, 100HEP, n=33 each) and received six patches containing grass pollen extract in weekly intervals before and during the pollen season of 2008.
The researchers observed that hay-fever symptom alleviation was dose dependent, with the highest dose group reaching statistical significance as compared to placebo (P<0.05). In the high dose group when compared to placebo, hay-fever symptoms during the peak of the pollen season 2008 were reduced by >30% and by 24% in the subsequent pollen season of 2009. Overall, the treatment was well tolerated. In the high dose groups, however, pruritus, erythema, wheal and eczema at the site of patch administration were frequent but mild.
The authors conclude that in the presented study, epicutaneous immunotherapy with 6 patches was safe and efficacious in a dose-dependent manner.
The Journal of Allergy and Clinical Immunology (JACI) is the official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.