Peanut allergy vaccine deemed safe, tolerable in phase 1 study
Key takeaways:
- Ara h 2 is bound to a cucumber mosaic vaccine so the body processes it as a virus instead of as an allergen.
- Most adverse events were local or were similar to those expected after receiving a vaccine.
SAN DIEGO — A hypoallergenic therapeutic vaccine candidate for peanut allergy was safe and tolerable, according to a poster presented at the 2025 American Academy of Allergy, Asthma & Immunology/World Allergy Organization Joint Congress.
“This vaccine is a cucumber mosaic vaccine that is bound to Ara h 2, which is the potent allergen in peanut,” Roxanne C. Oriel, MD, assistant professor of pediatrics, Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, told Healio.
The cucumber mosaic virus-like particles (VLP) in the VLP Peanut vaccine (Allergy Therapeutics), which are co-expressed with a tetanus toxin T-cell epitope, are genetically fused with Ara h 2. The vaccine presents Ara h 2 on the surface of the viral scaffold.
As a result, the researchers said, the immune system will process VLP Peanut as a harmless virus instead of as an allergen. The vaccine would then bypass typical allergic responses and trigger protective immunological changes, the researchers continued.
Designed to test VLP Peanut’s safety and tolerability, the PROTECT phase 1 trial is the first study of the vaccine in human beings, including 12 adults with peanut allergy and 12 adults with no peanut allergy, with both groups aged 18 to 50 years.
Participants received three escalating doses of VLP Peanut or a placebo over 3 months. Doses escalated by a factor of 50 for participants with peanut allergy and by a factor of 400 for those who did not have a peanut allergy.
“Local adverse events accounted for most problems that were reported by participants,” Oriel said. “The other symptoms that were experienced were ones that you expect after receiving a vaccine.”
Nine of the participants with a peanut allergy and 11 of those who did not have a peanut allergy experienced local adverse events such as pain, redness, warmth and tenderness at the injection site.
Six of the participants with a peanut allergy and five of those who did not have a peanut allergy experienced influenza-like symptoms such as runny nose, fatigue, headache, chills, sore throat and muscle aches.
Two patients with a peanut allergy experienced systemic adverse events, classified as grade 1 nausea and body itchiness. None of the patients who did not have a peanut allergy experienced a systemic adverse event.
Vital signs, spirometry and safety laboratory assessments all were classified as normal for all patients in both groups. Also, the patients who did not have a peanut allergy did not develop an allergy after receiving the vaccine, Oriel said.
“There’s some immunological changes that suggest that it works, which will be hopefully reported in the coming future,” she continued.
The researchers are now recruiting additional participants to continue the study.
“It is safe and it is tolerated,” Oriel said. “The next step would be to do a phase 2 to increase the number of individuals.”
For more information:
Roxanne C. Oriel, MD, can be reached at roxanne.oriel@mssf.edu.