Ukko, Inc., a Boston-based biotechnology company, has dosed the first participant in a Phase I/IIa clinical study evaluating UKK-0018 for peanut allergy, marking the first time the mRNA/lipid nanoparticle-encoded immunotherapy has been administered in humans.
UKK-0018 is a computationally designed modified peanut protein delivered via intramuscular injection of an mRNA/LNP formulation, where the protein is expressed in vivo following administration. The trial is designed to assess safety, tolerability, and preliminary efficacy across multiple doses and dosing intervals, with 32 participants enrolled across sites in Australia and New Zealand. Initial data are expected in early 2027. The study does not yet have a publicly listed registry identifier.
The mechanism centers on redirecting the immune response away from IgE-mediated allergic pathways. UKK-0018 is intended to induce protective IgG antibodies via B-cell activation and to expand allergen-specific T cells capable of inhibiting allergic responses. In preclinical mouse studies, the company reported rapid onset of protective IgG antibodies alongside T-cell modulation, with durable responses observed in anaphylaxis-prone animals. The LNP technology for the program has been provided by Acuitas Therapeutics Inc.
Research context
The immunological rationale for UKK-0018 rests on a well-established principle: peanut allergy is driven by aberrant IgE sensitization to peanut allergen proteins, and redirecting the immune system toward a protective IgG-dominant response can competitively suppress IgE-mediated degranulation. What distinguishes Ukko's approach is the combination of computational protein engineering — designed to reduce or eliminate IgE-binding epitopes while preserving immunogenic ones — with mRNA/LNP delivery, a platform that enables in vivo antigen expression following a small number of injections. The company has stated that the modified protein design is intended to reduce the risk of triggering allergic reactions during treatment itself, a persistent limitation of conventional allergen immunotherapy. Whether this translates into a meaningfully safer in-human profile is the central question the Phase 1/2a trial is designed to begin answering.
Peanut allergy management remains largely reactive. For most patients, strict allergen avoidance combined with access to epinephrine auto-injectors constitutes the standard approach. The only US FDA-approved disease-modifying therapy is Palforzia (peanut allergen powder-dnfp), an oral immunotherapy originally approved in January 2020 for patients aged 4–17 and expanded in July 2024 to include toddlers aged 1–3. Palforzia requires a prolonged up-dosing schedule spanning several months and daily maintenance dosing, and carries a risk of allergic reactions during the treatment course itself — factors that limit uptake. In February 2024, the FDA approved omalizumab (Xolair) for reducing allergic reactions from accidental exposure to multiple foods including peanut in patients aged one year and older, though omalizumab addresses reaction severity rather than the underlying sensitization and requires ongoing administration. No approved therapy offers durable protection from a short treatment course, and adult patients have particularly limited options. Ukko's stated aim — faster onset, fewer doses, and a more favorable safety profile compared to current oral immunotherapy — directly targets these gaps, though the clinical evidence to support those claims remains to be generated.