Cidofovir for treatment of progressive multifocal leukoencephalopathy in a newly diagnosed sarcoidosis patient - a valid therapeutic option?

Progressive multifocal leukoencephalopathy and immune reconstitution inflammatory syndrome in seven patients with sarcoidosis: a critical discussion of treatment and prognosis

Progressive multifocal leukoencephalopathy (PML) is a subacute brain infection by the opportunistic John Cunningham (JC) virus. Herein, we describe seven patients with PML, lymphopenia, and sarcoidosis, in three of whom PML was the first manifestation of sarcoidosis. At onset, the clinical picture comprised rapidly progressive spastic hemi- or limb pareses as well as disturbances of vision, speech, and orientation. Cerebral magnetic resonance imaging showed T2-hyperintense, confluent, mainly supratentorial lesions. Four patients developed punctate contrast enhancement as a radiological sign of an immune reconstitution inflammatory syndrome (IRIS), three of them having a fatal course. In the cerebrospinal fluid, the initial JC virus load (8–25,787 copies/ml) did not correlate with interindividual severity; however, virus load corresponded to clinical dynamics. Brain biopsies (n = 2), performed 2 months after symptom onset, showed spotted demyelination and microglial activation. All patients had lymphopenia in the range of 270–1150/µl.

To control JC virus, three patients received a combination of mirtazapine and mefloquine, another two patients additionally took cidofovir. One patient was treated with cidofovir only, and one patient had a combined regimen with mirtazapine, mefloquine, cidofovir, intravenous interleukin 2, and JC capsid vaccination. To treat sarcoidosis, the four previously untreated patients received prednisolone. Three patients had taken immunosuppressants prior to PML onset, which were subsequently stopped as a potential accelerator of opportunistic infections. After 6–54 months of follow up, three patients reached an incomplete recovery, one patient progressed, but survived so far, and two patients died. One further patient was additionally diagnosed with lung cancer, which he died from after 24 months. We conclude that the combination of PML and sarcoidosis is a diagnostic and therapeutic challenge. PML can occur as the first sign of sarcoidosis without preceding immunosuppressive treatment. The development of IRIS might be an indicator of poor outcome.

Progressive multifocal leukoencephalopathy in a patient post allo-HCT successfully treated with JC virus specific donor lymphocytes

BACKGROUND

Progressive multifocal leukoencephalopathy is a demyelinating CNS disorder. Reactivation of John Cunningham virus leads to oligodendrocyte infection with lysis and consequent axonal loss due to demyelination. Patients usually present with confusion and seizures. Late diagnosis and lack of adequate therapy options persistently result in permanent impairment of brain functions. Due to profound T cell depletion, impairment of T-cell function and potent immunosuppressive factors, allogeneic hematopoietic cell transplantation recipients are at high risk for JCV reactivation. To date, PML is almost universally fatal when occurring after allo-HCT.

METHODS

To optimize therapy specificity, we enriched JCV specific T-cells out of the donor T-cell repertoire from the HLA-identical, anti-JCV-antibody positive family stem cell donor by unstimulated peripheral apheresis [1]. For this, we selected T cells responsive to five JCV peptide libraries via the Cytokine Capture System technology. It enables the enrichment of JCV specific T cells via identification of stimulus-induced interferon gamma secretion.

RESULTS

Despite low frequencies of responsive T cells, we succeeded in generating a product containing 20 000 JCV reactive T cells ready for patient infusion. The adoptive cell transfer was performed without complication. Consequently, the clinical course stabilized and the patient slowly went into remission of PML with JCV negative CSF and containment of PML lesion expansion.

CONCLUSION

We report for the first time feasibility of generating T cells with possible anti-JCV activity from a seropositive family donor, a variation of virus specific T-cell therapies suitable for the post allo transplant setting. We also present the unusual case for successful treatment of PML after allo-HCT via virus specific T-cell therapy.