CP-174 Successful desensitisation in a patient with lenalidomide hypersensitivity

BackgroundA man with relapsed and refractory myeloma and previous neuropathy to intravenous chemotherapy (CyBorD) was treated with daily lenalidomide 25 mg orally plus dexamethasone. On the third day of treatment, more than 12 hours after taking the last lenalidomide pill, the patient presented with generalised macular erythema, periocular oedema, scalp pruritus and fever (38.0°C). Lenalidomide treatment was discontinued and he was successfully treated with systemic corticosteroids and antihistamines. The patient was subsequently referred to the allergy centre for desensitisation.PurposeLenalidomide plus dexamethasone is a highly effective regimen that has significantly improved outcomes in patients with multiple myeloma. Hypersensitivity reactions to lenalidomide may preclude its use in patients who would otherwise benefit from this treatment. We report a successful oral desensitisation protocol for lenalidomide in a patient with relapsed and refractory myeloma with hypersensitivity reaction to this drug.Material and methodsIn brief, lenalidomide was dissolved in isotonic sodium chloride and diluted to concentrations of 0.0025 mg/mL (solution A), 0.025 mg/mL (solution B) and 1 mg/mL (solution C). After pretreatment with dexamethasone, he was gradually given increasing lenalidomide doses to take orally at 15–60 min intervals (cumulative dose 25.2415 mg). The patient tolerated the escalating doses with no reaction and subsequently begun lenalidomide 15 mg daily, plus 8 mg dexamethasone 3 times per week. He tolerated continuous lenalidomide dosing with no evidence of recurrent hypersensitivity for 21 days.ResultsThis protocol was repeated on a monthly basis, and the patient has successfully completed 13 cycles of lenalidomide plus dexamethasone. During the desensitisation, he was monitored for any symptoms, skin or mucosal lesions, and had his blood pressure, heart rate, temperature and pulse oximetry regularly checked.ConclusionThe patient remains asymptomatic and free from any evidence of multiple myeloma progression. Limited literature exists on drug desensitisation with lenalidomide. This is a successful report of a lenalidomide desensitisation protocol. It supports the utility of adapted drug desensitisation in the oncology setting for lenalidomide administration in patients with drug hypersensitivity and without effective treatment alternatives.References and/or acknowledgementsAcknowledgements to all of the team.No conflict of interest