Mechanism of Action

Our mechanism of action is unique and differentiated as it targets specific epidermal dendritic cells, called Langerhans cells, which capture the antigen and migrate to the lymph node in order to activate the immune system without passage of the antigen into the bloodstream.

We believe our innovative EPIT® has the potential to offer compelling clinical benefits to patients suffering from severe allergies

Our Epicutaneous Approach Targeting Langerhans Cells has the Potential to Induce an Immune Reaction with a Highly Tolerogenic Profile

By delivering the allergen directly to the lymph node through the Langerhans cells, EPIT® activates specific regulatory T cells (Tregs) that can down-regulate the Th2-oriented reaction to the allergen. The absence of passage of allergens into the bloodstream explains the safety while the activity in the lymph node explains the efficacy of EPIT®.

Langerhans Cells

Our Viaskin® Patch Enables Continuous Antigen Exposure which has the Potential to Promote Sustained Tolerization to allergen via a Treg mechanism and epigenetic modifications

The Viaskin® patch contains allergen protein in its original antigenic state, which allows the skin to be continuously exposed to the allergen over time.

This continuous exposition leads to the activation of an orginal regulatory T cells (Tregs) population (Foxp3+, CTLA4+), maintaining the action after the end of treatment.

In parallel, EPIT® modulated Th2 and Tregs gene expression by inducing epigenetic modifications on gene promoters. 

The Safety Profile and Ease of Use of Viaskin® May Allow the Treatment of Allergies Very Early in Life

Because of its ease of use, well-demonstrated safety profile and deep immunomodulations, EPIT® will allow to treat all patients suffering from severe allergies, including very young children, without risk of anaphylaxis. This approach used for an early treatment of allergies in children during the “window of opportunity” which could prevent disease progression in these patients or the development of polyallergies.

The significant elements of the Viaskin® patch mechanism of action:

Phase 1

Containing a dry layer of allergen in its center, the patch is positioned on intact skin, without prior preparation.

Phase 2

The condensation chamber formed between the skin and the center of the patch creates hyperhydration of the skin and an accumulation of water.

Phase 3

The accumulation of water solubilizes the allergen. Due to this condensation chamber, the epidermis becomes more permeable allowing passage of the allergen into the epidermis.

Phase 4

Once in the epidermis, the allergen is captured by a population of highly specialized cells: Langerhans cells. These cells can take the protein at the surface of the skin, process it and present its epitopes to the lymphocytes in the lymph nodes.

Viaskin® targets the Unique Immunological Properties of Epicutaneous Langerhans Cells

Langerhans Cells

EPIT® can be applied in a broad range of immunotherapies

After the antigen has been presented to the T cells in the lymph node, it activates the Tregs, the main factor in the down-regulation of Th2 response, without causing any changes to Th1 expression. Th2 response is ultimately responsible for the production of IgE, which leads to allergic reactions. Sustained down-regulation of Th2 promotes long-term tolerance towards allergic exposure. 

Because of this unique mechanism of action, we believe EPIT® can be applied in a broad range of immunotherapies and desensitize patients without triggering systemic allergic reactions, such as anaphylaxis. 

We believe that EPIT® has the potential to provide all of the intended benefits of other disease-modifying allergy treatments, while avoiding the severe side effects associated with systemic reactions to the introduction of antigen.

Application of allergen onto intact skin by Viaskin® results in allergen delivery in the superficial layer of the skin without any diffuse passage neither in the dermis, the lymphatic system nor the bloodstream. In the epidermis, the allergen is uptaken by specialized immune cells, the Langerhans cells in the most superficial layer of the skin. After the capture of the allergen, Langerhans cells become active and migrate toward the draining lymph nodes where they induce immune modulations.