Maintaining oxaliplatin therapy after hypersensitivity reactions: real-world experience with a desensitisation protocol.

Hypersensitivity reactions (HSRs) to oxaliplatin occur in 7-25% of patients and pose a significant clinical challenge, particularly for individuals who otherwise benefit from oxaliplatin-based therapy. Although evidence supporting its efficacy remains limited, drug desensitisation protocols (DDPs) involving stepwise dose escalation have been adopted in clinical practice. This study describes the experience of a tertiary cancer centre with oxaliplatin desensitisation, focusing on recurrence of HSRs and treatment completion rates. A retrospective observational study was conducted at a comprehensive cancer centre between October 2019 and January 2024. Clinicopathological characteristics and oncological outcomes were examined for patients with gastrointestinal malignancies who received oxaliplatin-based chemotherapy using a DDP. Sixty-six patients underwent oxaliplatin desensitisation (median age 60 years; 55% female). Most had colorectal cancer (CRC) (n = 35, 53%) or upper gastrointestinal malignancies (n = 26, 39%); 85% (n = 56) were treated with palliative intent. The median number of oxaliplatin cycles prior to the first HSR was six (range 1-26). CAPOX (53%) and FOLFOX (42%) were the most common regimens associated with HSRs. Patients received a median of three cycles within the DDP (range 1-19). Most (76%) remained on their original systemic anti-cancer therapy without premature treatment modification. Sixteen patients (24%) experienced a recurrent HSR; however, 55 patients (83%) successfully completed their intended treatment. Outcomes during the desensitisation period included: no evidence of disease in eight patients (seven treated in the adjuvant setting), treatment response in 26 patients, and disease progression in 32 patients. Oxaliplatin desensitisation is feasible and enables most patients to continue systemic therapy, with low rates of treatment discontinuation and acceptable oncological outcomes. This approach should be considered for eligible patients who experience oxaliplatin-related HSRs to maintain access to effective chemotherapy.