Prota’s combination probiotic peanut oral immunotherapy (PRT100) is an investigational new drug being evaluated for its capacity to induce sustained unresponsiveness, also referred to as remission of allergy.
Four possible outcomes have recently been identified for the evaluation of treatments for peanut allergy:
- Desensitization is defined as an increase in reaction threshold to a food allergen while receiving active therapy and might equate to protection from accidental ingestion. Often, desensitization can be achieved after months of therapy and importantly only continues during therapy.
- Sustained Unresponsiveness (also referred to as Remission) is the long-lasting ability to tolerate a food after a period of treatment withdrawal (suggesting a re-programming of the immune response to the allergen). Sustained unresponsiveness can be assessed by performing a food challenge weeks or months after treatment is stopped (while avoiding the allergen).
- Long-term sustained unresponsiveness (long-term remission of allergy). Persistence of Sustained Unresponsiveness years after completing treatment, with ad libitum allergen intake in the intervening period, is referred to as “long-term sustained unresponsiveness” or “long-term remission of allergy”. Such enduring protection years after treatment may suggest ‘possible’ tolerance, however permanence of protection cannot be proven.
- Tolerance is defined as complete and permanent resolution of clinical response following exposure to any amount of the allergenic food after termination of therapy. There is currently no consensus on how to assess for the presence of tolerance since ‘permanence’ of an effect is difficult to establish within the context of a clinical study.
Prota Therapeutics is focused on the evaluation of their investigational lead product, PRT100 for the primary outcome of sustained unresponsiveness. Sustained unresponsiveness allows a person who was previously allergic to peanut to now eat peanut freely in their diet. This is possible because the protection provided with sustained unresponsiveness persists even when there is no peanut intake for weeks or months.
The Food Allergy Treatment Landscape
Prota’s technology employs a probiotic immune response modifier (IRM) intended to modulate the immune response to allergens, redirecting the response away from allergy towards tolerance.