Prota’s combination probiotic peanut oral immunotherapy (PRT100) is the only food allergy treatment in development that can deliver long-term sustained unresponsiveness, also referred to as long-term remission of allergy. PRT100 has been shown to be highly effective at inducing sustained unresponsiveness after 18 months of treatment, with benefits persisting for up to 4 years after treatment has been completed, indicating long-term remission of allergy.
- 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 the permanent ability to eat any amount of the food allergen without any further treatment or allergen exposure. 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 trial.
Sustained unresponsiveness allows a person who was previously allergic to peanut to now eat peanut freely in their diet. In other words, PRT100 treatment responders with sustained unresponsiveness may have peanut products as they wish, eating standard serves of peanut when they like or not eating peanut if they prefer, similar to how a person who is not allergic might eat peanut. This is possible because the protection provided with sustained unresponsiveness persists even when there is no peanut intake for weeks or months.
Other food allergy treatments in development aim to achieve desensitization. Desensitization is the temporary increase in the amount of food allergen an allergic person can eat before reacting, that is only maintained with ongoing regular (usually daily) antigen exposure or treatment. If regular allergen exposure is stopped, the protection is lost. More importantly, the level of protection that is provided with desensitization is not stable and can fluctuate, so a patient can react to doses of allergen that they have tolerated previously. For these reasons, patients who have been desensitized are usually advised to continue strict allergen avoidance (other than the allergen exposure taken through continuing treatment) and to maintain regular daily immunotherapy treatment.
The Food Allergy Treatment Landscape
Prota’s technology employs a probiotic immune response modifier (IRM) to modulate the immune response to allergens, redirecting the response away from allergy towards tolerance.