Objective: This study aimed to evaluate the incidence and severity of immediate hypersensitivity reactions (HSRs) in the first exposure to rituximab with the adoption of skin testing screening and desensitization and investigate the value of skin testing as a predictive tool for immediate HSR to rituximab.
Methods: This was a prospective intervention study. Patients with hematological malignancies who required rituximab were recruited. Skin testing screening with rituximab was conducted before the first infusion. Patients with positive skin testing results underwent desensitization, while those with negative results received rituximab at a standard infusion rate. All immediate HSRs were recorded, and the predictive value of positive skin testing results for immediate HSRs to rituximab was analyzed.
Results: In the 19 patients who adopted the novel protocol, six patients (31.6%) had immediate HSRs during the first infusion, with three mild reactions (15.8%), two moderate reactions (10.5%), and only one severe reaction (5.3%). The positive predictive value of intradermal test (IDT) with 1 mg/mL rituximab solution for immediate HSR was 100%, and the negative predictive value was 84.6%.
Conclusion: The protocol of skin testing screening and desensitization might have some potential to control the incidence and severity of immediate HSRs to rituximab during the first exposure. IDT result before the first infusion could become a useful predictor for immediate HSR to rituximab.
Keywords: rituximab, hypersensitivity, skin testing, predictive value of tests, desensitization, lymphoma