Toll-like receptors (TLRs) are emerging and potential allergen immunotherapy targets. TLR agonists may decrease Th2 responses and improve airway hyperresponsiveness, according to preliminary research. Furthermore, clinical trials are being conducted to assess the safety and effectiveness of TLR agonists for allergen immunotherapy in patients with allergic rhinitis and asthma. Pollinex Quattro and AIC, two allergy vaccines containing TLR agonists, have been studied in clinical studies too far. The former includes a TLR4 agonist, monophosphoryl lipid, and the latter has CpG patterns that activate the TLR9 cascade. Both of these allergy vaccinations have been shown to be safe and effective in controlling nasal symptoms in individuals with allergic rhinitis when given as a preseasonal subcutaneous injection. Clinical trials for allergic rhinitis and asthma are now underway for CRX-675, AZD8848, VTX-1463, 1018 ISS, and QbG10.
TLR agonists have shown promising effects in the treatment of allergic rhinitis and asthma using allergen immunotherapy. Future research should focus on using these drugs for food allergy immunotherapy as well.