Valdes, Daniel

e24165 Background: Taxanes are associated with a higher incidence of immediate hypersensitivity reactions (HSRs) compared to other classes of chemotherapeutic agents, even with adequate premedication. This study evaluates whether a titrated infusion protocol reduces the rate of first-dose HSRs to taxanes. Methods: This was a retrospective cohort study conducted at a single site hematology/oncology infusion center. The fixed-rate arm consisted of patients from January 2022 to July 2023 who received a fixed infusion rate for their first dose. The titration arm comprised patients from August 2023 to July 2024 who underwent a three-step titration protocol for their first dose. The primary endpoint was the rate of immediate HSRs during the first lifetime dose of docetaxel or paclitaxel. Secondary endpoints included HSR severity, HSRs during the first or second dose, and rate of treatment discontinuation due to HSRs. Results: Of 479 patients included (240 fixed-rate; 239 titration), HSRs occurred in 7.1% of the fixed-rate group and 11.3% of the titration group (OR 1.67, 95% CI 0.89-3.15; p= 0.1104). There were no differences in the severity of HSRs or in the rate of treatment discontinuation among both groups. Conclusions: The use of a titrated infusion protocol for first lifetime dose taxanes did not significantly reduce the incidence or severity of immediate HSRs. These findings suggest that a titration protocol may not confer additional benefits over fixed-rate in this setting. Primary and secondary endpoints. Fixed (N=240) Titration (N=239) OR 95% CI p-value Primary Endpoint Rates of immediate HSR 17 (7.1%) 27 (11.3%) 1.67 0.89- 3.15 0.110 Secondary Endpoints Severity of immediate HSR N=17 N=27 Grade 1 10 (58.8%) 8 (30.8%) 0.637 Grade 2 6 (35.3%) 12 (46.2%) 0.157 Grade 3 1 (5.9%) 6 (23.1%) 0.059 Rates of immediate HSR with first or second dose combined N=471 infusions N=453 infusions 26 (5.5%) 37 (8.2%) 1.52 0.91-2.56 0.111 Taxane administration time (min) N=239 N=232 1-hour infusion 71.8 92.8 3-hour infusion 187.6 201.6 Rates of medication discontinuation due to immediate HSR N=26 N=37 1 (3.8%) 8 (21.6%) 6.90 0.81-59.17 0.069

PURPOSE Taxanes are associated with a higher incidence of immediate hypersensitivity reactions (HSRs) compared with other classes of chemotherapeutic agents, even with premedication. This study evaluates whether a titrated infusion protocol reduces the rate of first-dose HSRs to taxanes. METHODOLOGY This was a retrospective cohort study conducted at a single-site hematology/oncology infusion center. The fixed-rate arm consisted of patients treated from January 2022 to July 2023 who received a fixed infusion rate for their first dose. The titration arm comprised patients treated from August 2023 to July 2024 who underwent a three-step titration protocol for their first dose. The primary end point was the rate of immediate HSRs during the first lifetime dose of docetaxel or paclitaxel. Secondary end points included HSR severity, HSRs during the first or second dose, and rate of treatment discontinuation because of HSRs. RESULTS Of 479 patients included (240 fixed-rate; 239 titration), HSRs occurred in 7.1% of the fixed-rate group and 11.3% of the titration group (odds ratio, 1.67 [95% CI, 0.89 to 3.15]; P = .1104). There were no differences in the severity of HSRs or in the rate of treatment discontinuation among both groups. CONCLUSION The use of a titrated infusion protocol for first lifetime dose taxanes did not significantly reduce the incidence or severity of immediate HSRs. These findings suggest that a titration protocol may not confer additional benefits over fixed-rate in this setting.