An overview of published studies exploring the use of therapeutic plasma exchange (TPE) in scleroderma patients indicated that the treatment improved Raynaud’s phenomenon and digital ulcers. Findings also showed that TPE made blood less viscous, improving blood flow and preventing blood vessels from becoming blocked.
The findings will be presented at the American College of Rheumatology (ACR)/ Association of Rheumatology Health Professionals (ARHP) 2016 Annual Meeting, being held in San Diego, California, on Nov. 11–16. The presentation is titled, “Therapeutic Plasma Exchange for the Treatment of Raynaud’s and Digital Ulcers in Systemic Sclerosis: A Systematic Review.”
Current medications for Raynaud’s phenomenon and digital ulcers mainly focus on drugs that improve blood flow in the smallest blood vessels, called capillaries, in the hands and feet. Although such drugs use varying mechanisms, they all act on the blood vessels themselves — relaxing the smooth muscles of the vessel walls to enlarge them, and so allow for a better blood flow.
But such treatment is not sufficient for many patients, and there is an unmet need for other approaches.
Researchers, led by Edward Harris of the Scleroderma Education Project — himself a patient who turned into an avid scleroderma scientist — reviewed all articles published between 1978 and 2016 exploring TPE as a scleroderma treatment.
Out of 40 identified articles, 13 had analyzed effects on Raynaud’s phenomenon and digital ulcers. Researchers excluded an additional four studies since patients had been on other scleroderma drugs while undergoing plasma exchange.
Together, the studies included 133 patients, and were mostly in the form of small pilot studies. One randomized clinical trial had 27 participants, of which nine received TPE. Another controlled trial explored the treatment in 37 patients, where nine patients with severe scleroderma were non-randomly chosen to receive plasma exchange.
Several studies reported that a single course of treatments — most often one treatment per week for four weeks — improved Raynaud’s symptoms, digital ulcers, blood flow, and vessel parameters, with symptoms frequently reported to entirely disappear.
Studies often reported long-standing effects of at least six months. In one study involving 18 patients, digital ulcers had not re-emerged at a three-year follow-up visit.
In contrast to current medications, TPE does not impact blood vessels. An earlier study has, however, suggested that patients with active digital ulcers have an abnormally thick, or viscous, blood.
Researchers think that the treatment works by reducing the aggregation of red blood cells. Such aggregates, they reason, get stuck in the tiny vessels in hands and feet, hindering blood flow and destroying the vessels.
Harris and the research team recommends that these aspects, particularly focusing on blood characteristics, should be explored in a clinical trial of TPE.
Harris has previously published a case report of his own treatment, spanning 22 years of TPE, and suggested guidelines to ensure potential future clinical trials can follow the same treatment and study protocols.