Cyclophosphamide for neurological conditions at a tertiary neuroscience centre: a retrospective case series

<h3></h3> Cyclophosphamide is an alkylating agent of nitrogen mustard type 2. It is used to treat an array of neuroimmunological disorders. We conducted a single centre retrospective review of cases treated with cyclophosphamide between 2017 and 2022 at a tertiary neuroscience centre. Demographics (age, sex, ethnicity, BMI), clinical indication, dosage and clinical outcomes were collected. A total of 53 patients were treated with a mean age of 56.5 years. The most common indication was Vasculitis affecting 60.4% (32/53) of patients. Non- vasculitic indications included autoimmune encephalitis, inflammatory non-vasculitic neuropathies, neurosarcoidosis and immune checkpoint inhibitor associated myasthenia gravis. Remission rates were higher for the vasculitides at 76.0% (19/25) compared with non- vasculitic conditions at 41.7% (5/12). Patients received either a Cyclops trial derived protocol (64.2%, 34/53) or monthly pulsed based on surface area (30.2%, 16/53) or the Eurolupus protocol (5.7%, 3/53). Cyclophosphamide had the highest efficacy treating vasculitides with a remission rate similar to controlled trials in systemic vasculitis. Non-vasculitic indications had a higher rate of treatment failure. Both groups lacked documentation of how disease activity was monitored and remission was defined. Further study is required to determine the rate of adverse incidents and treatment tolerance.