One-Dilution Rapid Desensitization Protocol to Chemotherapeutic and Biological Agents: A Five-Year Experience

BACKGROUND: Rapid drug desensitization (RDD) becomes a crucial procedure to allow treatment continuation in patients who suffer drug hypersensitivity reactions (DHRs) to chemotherapeutic (CMT) and biological agents (BA). OBJECTIVE: The aim of the study was to compare the efficacy and safety of a one-bag dilution protocol (1DP) with a conventional three-bag dilution protocol (3DP) for desensitization of patients with CMT or BA hypersensitivity. METHODS: Retrospective analysis of patients with immediate DHRs to CMT or BA who underwent at least 1 RDD procedure in our department between 2014 and 2019 was performed. Demographical data, clinical history, skin tests, tryptase levels, and risk assessment were registered. The safety, tolerability, occurrence, and severity of breakthrough reactions (BTR) with 3DP and 1DP were compared. RESULTS: After the allergy workup, 157 patients fulfilled criteria to undergo RDD (137 females, mean age: 60.44 - 12.6 years). A total of 639 RDDs (543 CMT and 96 BA) were performed using 3DP in 205 (48 patients) and 1DP in 434 (109 patients). Almost all procedures (636) were completed successfully. No BTR occurred in the first RDD in 52% and 51% of the 3DP and 1DP, respectively. Most BTR were mild. Moderate-severe BTR occurred in 17% with 3DP and 9% with 1DP. There were no statistical differences between protocols regarding the rate and severity of BTR. CONCLUSIONS: RDD with 1DP to CMT and BA has equivalent outcomes to a 3DP desensitization in a selected population of patients in terms of efficacy, tolerability, and safety. Moreover, 1DP reduces the time required for RDD and simplifies the logistics. (C) 2021 American Academy of Allergy, Asthma & Immunology.