Plasma Exchange with 5% Albumin Associated with Marked Stabilization of Brain Perfusion in Alzheimer’s

Plasma exchange (PE) with 5% albumin replacement was associated with marked stabilization of brain perfusion in patients with mild to moderate Alzheimer’s disease during a 21-week treatment period and reduced perfusion loss compared to control subjects at six-month follow-up, according to findings from a sham-controlled Phase II clinical trial.

Of 42 patients recruited for this study, 37 were analyzed, including 18 treated with PE and 19 controls. Evaluable patients received treatment for 21 weeks, divided into one intensive and two maintenance periods. Brain perfusion was assessed by SPECT scans using an automated software program, and brain structural changes were assessed by MRI, at weeks 0 (baseline), 21 and 44.

After six months, PE-treated patients experienced less cerebral perfusion loss than controls in frontal, temporal and parietal areas. Notably, perfusion was stabilized in the language-related Brodmann area BA38-R during the PE treatment period (p<0.05). Statistical parametric mapping analysis showed stabilization or absence of progression of perfusion loss in PE-treated patients until week 21, in contrast to significant worsening of perfusion in the control group at all time points. There was a trend toward decreasing hippocampal and total intracranial volume for both patient groups during the study.

The investigators noted that these brain perfusion findings could be related to previously documented mobilization of amyloid-β peptide in CSF and plasma and improved cognitive performance in this same PE-treated group compared to controls. They anticipate that the ongoing Phase III AMBAR (Alzheimer Management by Albumin Replacement) trial sponsored by Grifols will help shed further light on these relationships.