A 1-day imported fire ant rush immunotherapy schedule with and without premedication

Area of Science:

• Allergy and Immunology
• Clinical Trials
• Immunotherapy

Background:

• Rush immunotherapy (RIT) offers rapid protection against imported fire ant (IFA) stings.
• Evaluating expedited immunotherapy protocols is crucial for patient management.

Purpose of the Study:

• To assess the safety and efficacy of a 1-day RIT protocol using IFA whole body extract (WBE).
• To determine the impact of antihistamine and prednisone premedication on RIT safety and efficacy.

Main Methods:

• A 1-day RIT protocol involving 10 injections was administered to patients with systemic IFA reactions.
• The protocol was revised to include a 3-day premedication regimen (prednisone, ranitidine, loratadine) after initial safety concerns.
• Efficacy was evaluated via sting challenges approximately 22 days post-RIT.

Main Results:

• The initial 1-day RIT without premedication had a systemic reaction rate (SRR) of 24.3%.
• The revised protocol with premedication showed a reduced SRR of 9.5% (P = .07).
• The RIT protocol demonstrated high efficacy (98.1%) with only one mild reaction during sting challenges.

Conclusions:

• One-day RIT using IFA WBE is an efficacious treatment for IFA hypersensitivity.
• Premedication showed a trend towards reducing systemic reaction rates during RIT.
• Larger trials are required to confirm the safety benefits of premedication in RIT.