JACI Study Finds Allergen Immunotherapy Safe, Despite Proposed Regulations

In an article published by The Journal of Allergy and Clinical Immunology (JACI) earlier this month, researchers from Massachusetts General Hospital have confirmed the safety of current allergen immunotherapy (AIT or allergy shots) practices.

"Even though there are no reports of infection resulting from allergy shots, proposed United States Pharmacopeia (USP) regulations would restrict allergen compounding and drastically limit patients' access to allergy shots. We sought to explore the safety of current AIT practices by examining the historical risk of infection from allergy shots in a large patent population through an integrated healthcare system," said senior author Aidan Long, MD, FAAAAI.

Allergy shots are a cost-effective, disease modifying treatment that has been used for the past century to successfully treat allergic rhinitis, allergic conjunctivitis, asthma and stinging insect allergies. This treatment helps 2.6 million patients in America every year for an estimated total of 16 million annual injections. Adverse reactions to allergy shots are typically limited to local (0.7-4.0 percent) and systemic (0.2 percent) allergic reactions, but data is scant on the risk of infection caused by this treatment.

Therefore, investigators analyzed ten years' of data from the Partners Research Patient Database Repository (RPDR), a storehouse of all electronic health record data within the health system that includes Massachusetts General Hospital and Brigham and Women's Hospital. In total, they examined 3,242 patient records who received a total of 136,322 injections.

"We found 86 episodes of infections occurring within five days of receiving an allergy shot, but, after reviewing these patients' charts, determined that all soft tissue infections were at sites not related to the allergy shot. Likewise, none of the systemic infections could be attributed to allergy shots," Long said.

This study was prompted by proposed changes to rules for sterile compounding of medications developed by the USP. Current USP standards for sterile compounding fall into three separate categories reflecting the risk associated with procedures in each category, with AIT treated separately from those categories reflecting its extremely low infectious risk.

The new proposed rules subject AIT compounding to the same restrictive and costly environmental and engineering controls, sterility testing requirements and shortened beyond use dates applicable to rules designed for high risk preparations intended for intravenous, spinal or other systemic means of administration.

The safety record of AIT extract preparation in an allergist's office using aseptic technique is well-established in clinical practice going back over 100 years. Further, this preparation of allergen extracts is different from pharmacy compounding. AIT patients benefit from a unique patient/physician relationship as they are monitored by the physician at least 30 minutes post-injection for reactions, return for at least monthly injections, undergo routine examinations and receive ongoing care. Allergen extract injections are only administered subcutaneously and in small volumes (0.5 to 1.0 mL) yet are completely individualized to the patient based on a prescription established by the allergist. They are never injected intravenously, into the central nervous system or into body cavities.

"Out of the many millions of injections, administered to millions of patients, over several decades, there are no reported infections. In this study, our team also found zero reported infections due to AIT. It's clear that the sterility and safety practices in place during the study period are adequate in preventing adverse infectious outcomes related to the preparation and administration of AIT," Long concluded.

The AAAAI represents allergists, asthma specialists, clinical immunologists, allied health professionals and others with a special interest in the research and treatment of allergic and immunologic diseases. Established in 1943, the AAAAI has more than 6,900 members in the United States, Canada and 72 other countries. The AAAAI's Find an Allergist/Immunologist service is a trusted resource to help you find a specialist close to home.