Increases in brain white matter abnormalities and subcortical gray matter are linked to CD4 recovery in HIV infection.

MRI alterations in the cerebral white (WM) and gray matter (GM) are common in HIV infection, even during successful combination antiretroviral therapy (CART), and their pathophysiology and clinical significance are unclear. We evaluated the association of these alterations with recovery of CD4+ T cells. Seventy-five HIV-infected (HIV+) volunteers in the CNS HIV Anti-Retroviral Therapy Effects Research study underwent brain MRI at two visits. Multi-channel morphometry yielded volumes of total cerebral WM, abnormal WM, cortical and subcortical GM, and ventricular and sulcal CSF. Multivariable linear regressions were used to predict volumetric changes with change in current CD4 and detectable HIV RNA. On average, the cohort (79 % initially on CART) demonstrated loss of total cerebral WM alongside increases in abnormal WM and ventricular volumes. A greater extent of CD4 recovery was associated with increases in abnormal WM and subcortical GM volumes. Virologic suppression was associated with increased subcortical GM volume, independent of CD4 recovery. These findings suggest a possible link between brain alterations and immune recovery, distinct from the influence of virologic suppression. The association of increasing abnormal WM and subcortical GM volumes with CD4+ T cell recovery suggests that neuroinflammation may be one mechanism in CNS pathogenesis.

Direct intracerebral delivery of cintredekin besudotox (IL13-PE38QQR) in recurrent malignant glioma: a report by the Cintredekin Besudotox Intraparenchymal Study Group.

PURPOSE: Glioblastoma multiforme (GBM) is a devastating brain tumor with a median survival of 6 months after recurrence. Cintredekin besudotox (CB) is a recombinant protein consisting of interleukin-13 (IL-13) and a truncated form of Pseudomonas exotoxin (PE38QQR). Convection-enhanced delivery (CED) is a locoregional-administration method leading to high-tissue concentrations with large volume of distributions. We assessed the use of intracerebral CED to deliver CB in patients with recurrent malignant glioma (MG). PATIENTS AND METHODS: Three phase I clinical studies evaluated intracerebral CED of CB along with tumor resection. The main objectives were to assess the tolerability of various concentrations and infusion durations; tissue distribution; and methods for optimizing delivery. All patients underwent tumor resection followed by a single intraparenchymal infusion (in addition to the intraparenchymal one following resection), with a portion of patients who had a preresection intratumoral infusion. RESULTS: A total of 51 patients with MG were treated including 46 patients with GBM. The maximum tolerated intraparenchymal concentration was 0.5 microg/mL and tumor necrosis was observed at this concentration. Infusion durations of up to 6 days were well tolerated. Postoperative catheter placement appears to be important for optimal drug distribution. CB- and procedure-related adverse events were primarily limited to the CNS. Overall median survival for GBM patients is 42.7 weeks and 55.6 weeks for patients with optimally positioned catheters with patient follow-up extending beyond 5 years. CONCLUSION: CB appears to have a favorable risk-benefit profile. CED is a complex delivery method requiring catheter placement via a second procedure to achieve accurate catheter positioning, better drug distribution, and better outcome.