Patienter med en behandlingsanamnese med immunosuppresive lægemidler, herunder cyclophosphamid og mitoxantron, kan opleve langvarig immunosuppression og kan derfor have øget risiko for at udvikle PML.
Patients with a treatment history of immunosuppressant medications, including cyclophosphamide and mitoxantrone, may experience prolonged immunosuppression and therefore may be at increased risk for PML.