T-cell Therapy in Patients With PML

Inclusion Criteria: * Adults\* aged ≥ 18 years with PML (diagnosed ≤ 60 days before screening) associated with one or more of the following risk factors: lymphoproliferative diseases, immunosuppressive therapy, or lymphopenia * Signed written informed consent from subject and/or legal representative * HPyV-2 detection in CSF by PCR analysis or in brain biopsy Exclusion Criteria: * PML caused by HIV * PML caused by natalizumab * PML occurring within five 5 years after hematopoietic stem-cell transplantation or CAR T cell therapy, or resulting from chronic lymphocytic leukemia (CLL) * Patients who are unable to follow the study protocol, either on their own or with the support of a reliable representative, will be excluded * Pregnancy or breastfeeding * Currently receiving chemotherapy * Present (within 2 weeks before screening visit) and continuous treatment with immune checkpoint inhibition therapy * Severe infections other than PML (e.g. sepsis, pneumonia) * Hypersensitivity to any of the components of the medications used * Inability to undergo MRI examination (e.g. implanted incompatible medical devices, claustrophobia) * Participation in another clinical trial (other investigational drugs or devices at the time of enrolment or within 30 days prior to enrolment)