Vasogen Inc -
Vasogen's receives VasoCare results
Wednesday Nov 3 1999
Dr. Eldon Smith reports
Vasogen Inc. has received the results of a placebo-controlled double-blind clinical trial of its VasoCare therapy for the treatment and prevention of atherosclerosis -- the major cause of heart disease, strokes, and peripheral vascular disease. The trial showed a significant improvement in the rate of recovery of both skin blood flow and tissue oxygen levels following ischemia, indicative of improved functioning of the blood vessels, in patients with advanced peripheral vascular disease (PVD).
PVD is a serious form of cardiovascular disease resulting from atherosclerosis (hardening of the arteries) that affects the arteries supplying blood to the legs. In addition to having reduced blood flow to the lower limbs as a result of atherosclerosis of the large arteries, patients with advanced PVD also have generalized impairment of the microcirculation, which provides vital oxygen and nutrition to tissues, including the skin. This is believed to result from dysfunction of the endothelium (the cellular lining of blood vessels that regulates blood flow and inhibits clotting).
In this study, conducted at the University Hospital, Lund, Sweden, under the direction of Professor Lars Edvinsson, department of internal medicine, changes in the recovery rate of skin blood flow and oxygen tension following total temporary occlusion of blood flow were measured in the extremities of patients with advanced PVD. Eighteen patients were randomly assigned to one of two groups: one group received two courses of VasoCare therapy over a nine-week period, and a control group received two courses of a placebo treatment.
In patients receiving VasoCare therapy, improvement in the rate of recovery of skin blood flow was noted as early as six weeks after the initiation of therapy. At 18 weeks, the rate of recovery of skin blood flow was significantly faster in the VasoCare group when compared with baseline (recovery time 27 per cent of baseline, p less than 0.05, paired t-test), whereas in the control group there was no significant change. Recovery of skin oxygen content was also significantly faster in the VasoCare group at 18 weeks (p less than 0.03, paired t-test). Despite the limited number of patients enrolled in the study (n=9 in each group), additional analysis, using repeated measures ANOVA, revealed a strong statistical trend toward improvement in skin blood flow responses throughout the posttreatment period in the VasoCare group when compared to the control group (one-sided p value = 0.065).
Taken together, the Lund results provide evidence that VasoCare therapy improves the microcirculation in patients with atherosclerosis and suggest an improvement in endothelial function. Interventions that improve endothelial function have been shown to reduce serious events, such as heart attack and stroke, in patients suffering from atherosclerosis.
"VasoCare therapy provided a surprisingly long-lasting improvement in responses of skin blood flow in patients with advanced PVD," said Dr. Edvinsson. "Impaired skin blood flow can lead to tissue breakdown and the formation of slow healing ulcers, which puts patients with advanced PVD at increased risk for amputation. A therapy with the ability to improve skin blood flow would minimize these costly and debilitating problems that accompany progression of the disease."
In addition to continuing and planned clinical research in the area of cardiovascular disease, the company's preclinical research program is investigating the impact of VasoCare therapy on the immune-mediated inflammatory component of atherosclerosis. Preclinical research at the University of Toronto has demonstrated that VasoCare therapy reduces the progression of atherosclerosis by up to 75 per cent. The University of Toronto researchers are now investigating the effect of VasoCare therapy on atherosclerosis in additional model systems and further investigating the therapy's anti-inflammatory mechanisms.
"The findings of the Lund study represent an important milestone," said Dr. Eldon Smith, Vasogen's vice-president of scientific affairs. "By providing evidence of a favourable effect on endothelial function, this study represents the first crucial link between preclinical models, where VasoCare therapy has shown a marked impact on atherosclerosis, and patients with the disease."
Currently, more than five million people in North America and Europe have symptomatic PVD -- a number that is increasing as the population ages. PVD patients have a risk of heart attack and stroke that is up to 10 times greater than the general population. Health care costs resulting from PVD exceed $10-billion annually.
Vasogen is developing proprietary immune modulation therapies to advance the treatment of cardiovascular, autoimmune and related inflammatory diseases. These therapies are designed to target fundamental disease-causing events, providing safe, effective treatment. |
