IgE-mediated anaphylaxis induced by pembrolizumab

Area of Science:

• Oncology
• Immunology
• Allergy & Immunology

Background:

• Biologics, including pembrolizumab, are increasingly used in cancer therapy.
• Drug-related hypersensitivity reactions (HSR) are a growing concern with biologic use.
• Pembrolizumab-induced HSR are rarely reported, with limited allergy testing data.

Purpose of the Study:

• To report a case of severe hypersensitivity reaction to pembrolizumab.
• To highlight the diagnostic utility of allergy testing in pembrolizumab-induced HSR.
• To review existing literature on pembrolizumab-related HSR.

Main Methods:

• Case report of a patient experiencing anaphylaxis during pembrolizumab treatment.
• Allergy testing, including skin tests, to confirm IgE-mediated hypersensitivity.
• Literature review of previously reported pembrolizumab-induced HSR.

Main Results:

• A 77-year-old male developed severe anaphylaxis during his 8th pembrolizumab infusion for metastatic lung adenocarcinoma.
• Allergy tests confirmed a type I, IgE-mediated hypersensitivity mechanism.
• Literature review identified four prior cases, indicating HSR can occur after multiple courses.

Conclusions:

• Immediate HSR to pembrolizumab can manifest as severe anaphylaxis after several treatment cycles.
• Mild preceding symptoms warrant close monitoring for potential HSR.
• Skin tests are reliable for diagnosis, and rapid drug desensitization is a viable management option.