A Pilot Study of Omalizumab to Treat Oxaliplatin-Induced Hypersensitivity Reaction

Background: Oxaliplatin hypersensitivity reactions (HSRs) are immunoglobulin E (IgE)-mediated and prevent maximum benefit from this drug. This study was designed to determine whether oxaliplatin HSRs could be prevented or reduced with omalizumab (Xolair), an anti-IgE antibody. Patients/Methods: This was a single-arm prospective pilot study. Patients receiving oxaliplatin-based chemotherapy for gastrointestinal cancers who were experiencing grade 1/2 HSRs were eligible. Patients received omalizumab 300 mg subcutaneously every 2 weeks, alternating with oxaliplatin-based chemotherapy. Nine patients enrolled. The primary end point was reduction of repeat HSR over the next 2 cycles. The sample size of 12 patients would achieve 79% power to detect a decrease from HSR rate of 70% (the null hypothesis) to 35% using a 1-sided binomial test. The study would be considered positive if fewer than 6 HSR events over 2 cycles occurred on omalizumab. Results: Nine patients received 58 cycles of omalizumab. The mean number of treatments was 6 (range, 1-12). Eight of 9 patients (88%) completed 2 or more cycles and 7 (78%) completed 4 or more cycles; the overall rate of HSR was 12%. Five of 7 evaluable patients had stable disease, including 1 with near partial response. Conclusions: Omalizumab reduces or abrogates oxaliplatin HSRs and allows months of additional therapy with apparent clinical benefit. Keywords: gastrointestinal malignancies, oxaliplatin, hypersensitivity reaction, omalizumab Trial registration: Role of Omalizumab in Reducing the Incidence of Oxaliplatin-induced Hypersensitivity Reaction ClinicalTrials.gov Identifier: NCT02266355
Introduction Oxaliplatin is a third-generation platinum alkylating agent that has demonstrated efficacy against a variety of tumor types, both in adjuvant and metastatic regimens. (1-6 ) Oxaliplatin is widely used [...]