Norwegian pilot study replaces plasma in 12 patients with early Alzheimer’s disease with plasma from donors aged 18–24
Norwegian pilot study replaces plasma in 12 patients with early Alzheimer’s disease with plasma from donors aged 18–24
On July 23, researchers published a report from an open-label pilot study in which participants with mild cognitive impairment and biomarkers of Alzheimer’s disease had 16 to 26 liters of their own plasma replaced with plasma from donors aged 18–24. The researchers compared three treatment schedules, the burden of the procedure on patients, and adverse events.
Plasma is the liquid component of blood and contains proteins, hormones, and signaling molecules. During plasma exchange, a machine removes a patient’s plasma while simultaneously returning a replacement fluid. In an earlier Alzheimer’s disease study, plasma was replaced with albumin and saline. In this study, the replacement fluid was plasma from young donors, and the total volume exchanged over the course of treatment reached tens of liters.
The authors designed the treatment schedule around interstitial fluid, the fluid surrounding cells within tissues. Their model assumes that the human bloodstream contains about three liters of plasma, while the interstitial compartment contains about twelve liters of fluid. The transfer of albumin and IgG between these compartments was expected to take approximately 48 hours. The intensive schedule therefore consisted of nine to ten procedures, each using three bags of plasma, performed every two to three days. Four participants underwent an average plasma exchange volume of 17.4 liters over 23.8 days. The authors describe the intended change in the composition of this fluid as “rejuvenation of the interstitial environment.”
This course of treatment requires compatible donor plasma, an exchange machine, a nurse, a physician, and monitoring for reactions. All 12 participants completed their assigned treatment course. The study recorded 59 adverse events. Events that the authors attributed to the procedure included urticaria, symptoms of reduced calcium levels, cough, and dizziness. Three cases of generalized urticaria required the current procedure to be stopped and the patient to receive treatment.
The intensive schedule cost approximately 6650 euros per person. The authors propose using it as the basis for a subsequent controlled trial that would compare clinical outcomes.