therapeutic dosage. Infusion of donor T cells specific to the related BK polyomavirus has shown possible effect in treating PML in one small study by Katy Rezvani's group, but needs further study. In December 2021, Cellevolve announced it is launching a clinical trial for the treatment of PML utilizing BK virus specific T-cells (VSTs). Prognosis One-third to one-half of people with PML die in the first few months following diagnosis, depending on the severity of their underlying disease. Survivors can be left with variable degrees of neurological disability. See also Joseph Berger (neurologist) Leukoencephalopathy Leukoencephalopathy with vanishing white matter Toxic leukoencephalopathy Pedro Zamora It's My Party (film) References External links Overview at NIH Brain disorders Viral infections of the central nervous system Rare diseases Slow virus diseases Rare infectious diseases