D1.243 - L-asparaginase desensitization in children

The potential for hypersensitivity reactions to limit the use of chemotherapeutic drugs is a significant concern, given the risk of life-threatening reactions. L-asparaginase, an antineoplastic agent utilised in the treatment of acute lymphoblastic leukaemia (ALL) and certain other malignant diseases, is associated with a high incidence of hypersensitivity reactions. In instances where the utilisation of L-asparaginase is imperative in chemotherapy and no alternative pharmaceutical agent is available, desensitisation is of paramount importance.The present study aims to present the data of cases that underwent L-asparaginase desensitisation in our clinic.

In the period between 2022 and 2024, patients with a documented history of anaphylaxis to L-asparaginase and no alternative treatment options were subjected to a desensitization protocol at the Akdeniz University Faculty of Medicine Paediatric Allergy-Immunology Clinic, and patients were subsequently monitored for possible allergic reactions.

A total of 8 patients underwent a desensitisation protocol 10 times. The desensitisation protocol involved the administration of two different concentrations of L-asparaginase, comprising a total of 11 steps, and was used in the management of the cases studied. Prior to desensitisation, methylprednisolone was administered at 2 mg/kg/dose (maximum: 60 mg/day) at -13, -7 and -1 hours, while hydroxyzine was administered at 1 mg/kg/dose (maximum: 25 mg/day) at -1 hour. It was also be reported that one of the patients had a documented history of anaphylaxis to beta-lactam antibiotics. One of the patients had a history of taking L-asparaginase at a dose higher than 6000 units/m2/day. Two patients underwent a second desensitisation protocol because they needed to take L-asparaginase again after a long period of time after desensitisation. During desensitisation, a local allergic reaction was observed in one patient, but was found to have resolved during subsequent follow-up. All patients' protocols were successfully completed. Patients were found to be able to continue their cancer treatment safely.

In countries where alternative L-asparaginase preparations are in short supply, desensitisation may be a more appropriate option. Desensitisation is vital in situations where the administration of chemotherapeutic drugs is necessary, such as in cancer patients, and where there is no alternative to the allergenic drug.