InnoUp Farma, a Spanish biotechnology company, has announced the successful completion of its Phase 1 clinical trial for INP20, an innovative oral immunotherapy candidate designed to treat peanut allergy. Peanut allergy is among the most common and potentially severe food allergies worldwide, placing a significant burden on patients and families who must remain constantly vigilant against accidental exposure. While still in the early stages of development, this clinical milestone represents an encouraging step toward a new approach that aims to retrain the immune system rather than simply reduce allergic reactions.
The Phase 1 clinical trial enrolled 52 patients between the ages of 12 and 65 who received a once-daily dose of INP20 for 14 days. The study’s primary objectives were to evaluate safety and early immune modulation, yielding encouraging preliminary results. Researchers reported an 8.9-fold increase over baseline levels of peanut-specific immunoglobulin G4 (IgG4), a biomarker commonly associated with the development of immune tolerance during successful allergen immunotherapy. Remarkably, IgG4 levels continued to increase for two weeks after participants received their final dose.
Importantly, this early-stage study was designed to evaluate safety and immune responses—not whether patients could safely consume larger amounts of peanut without experiencing an allergic reaction. Demonstrating meaningful clinical protection will require larger Phase 2 and Phase 3 studies.
Unlike traditional oral immunotherapy, which gradually introduces increasing amounts of peanut protein over many months and is associated with frequent allergic reactions—including occasional severe reactions—INP20 is designed around an entirely different concept. Rather than relying solely on repeated exposure to peanut protein, the therapy aims to “replicate the biological signals generated by the gut microbiota that naturally promote tolerance to food.”
To accomplish this, INP20 employs nanotechnology to encapsulate peanut extract inside microscopic nanoparticles measuring only a few billionths of a meter. Instead of presenting peanut proteins directly to the immune system, the treatment is intended to alter how the immune system encounters the allergen by delivering it in a controlled nanoparticle formulation. Researchers hope this specialized delivery system creates a carefully orchestrated “handshake” with the immune system that encourages a more tolerant response.
The scientific foundation for this approach was established in earlier laboratory research published in the Journal of Allergy and Clinical Immunology. Scientists engineered human reporter cells to evaluate how the treatment interacted with Toll-like receptors (TLRs)—immune sensors that help regulate immune responses. They found that while peanut extract alone failed to activate these receptors, peanut extract encapsulated within INP20’s nanoparticles produced potent, synergistic activation of both TLR2 and TLR4. The investigators also demonstrated that empty nanoparticles activated only TLR2, highlighting that both the nanoparticle formulation and encapsulated peanut extract were necessary to activate TLR4.
Researchers believe simultaneous activation of TLR2 and TLR4 may promote regulatory immune pathways, including increased production of interleukin-10 (IL-10), an anti-inflammatory signaling protein associated with immune tolerance.
By targeting these immune signaling pathways, the company says INP20 is intended to “address the underlying mechanisms responsible for immune tolerance, targeting the root cause of food allergies rather than simply reducing symptoms or allergic reactions.” If future studies confirm this approach, the therapy could represent a significant advance in food allergy treatment by promoting deeper and potentially more durable immune modulation than existing therapies. Furthermore, because the nanoparticle platform determines how the immune system encounters the allergen, researchers believe it could theoretically be adapted to treat other food allergies, including milk, egg, and tree nuts.
With Phase 1 completed successfully, InnoUp Farma is preparing to launch Phase 2 clinical trials to determine the optimal dosage and evaluate longer-term safety and efficacy over a six-month treatment period. The company also reports that the full Phase 1 findings are currently undergoing peer review for potential publication in Nature Medicine. If future trials confirm these encouraging early immune findings and demonstrate meaningful clinical protection, INP20 could become an important addition to the next generation of food allergy immunotherapies.
