10-year safety follow-up in patients with local VEGF gene transfer to ischemic lower limb.

Vascular endothelial growth factor (VEGF)-mediated gene therapy (GT) has shown promising results as a novel method in the treatment of severe cardiovascular diseases. VEGF GT has proved to be safe and well tolerated in short-term studies, but there is only very limited data available on long-term effects. In this study we examined the effects of VEGF GT on patients having received VEGF-A gene transfer for the treatment of symptomatic (that is, claudication or critical lower limb ischemia) peripheral arterial occlusive disease. Out of 54 patients, 25 (46%) were interviewed for this study and 26 (48%) had died during the follow-up. Interviewed patients were treated with adenoviral (n=8, mean age 76 (62.7-90.6) years) or plasmid/liposome (n=8, mean age 84.2 (71.9-94.7) years) vectors compared with a randomized control group (n=10, mean age 80.5 (70.7-88.1) years) using a local balloon catheter device. The follow-up time was 10 years. Causes of death were clarified from hospital records. There were no statistically significant differences between the study groups in the causes of death or in the incidence of cancer (VEGF-Adv 0/10 vs VEGF-p/l 1/8 vs Control 1/7, P=0.5), diabetes (3/10 vs 3/8 vs 2/7, P=1.00) or diabetic retinopathy (0/10 vs 1/8 vs 0/7, P=0.45). In addition, we found no differences in the number of amputations of the treated leg (0/10 vs 3/8 vs 1/7, P=0.17). We conclude that transient VEGF-A-mediated GT did not increase the incidence of cancer, diabetes, retinopathy or any other diseases during the 10-year follow-up time. No significant differences were detected in the number of amputations or causes of death. This study supports our previous findings that local adenovirus and plasmid/liposome-mediated VEGF-A GT is safe and well-tolerated treatment in elderly patients with cardiovascular diseases.

Eight-year safety follow-up of coronary artery disease patients after local intracoronary VEGF gene transfer.

Vascular endothelial growth factor (VEGF) has been shown to stimulate angiogenesis and myocardial perfusion. The short-term safety of VEGF gene therapy is excellent. However, there are only limited results regarding the long-term effects. The Kuopio Angiogenesis Trial (KAT) studied the efficiency and short-term safety of the local VEGF-A(165) gene transfer in 103 patients with coronary artery disease. Three patient groups received either VEGF as an adenoviral (n=37), or as a plasmid/liposome vector (n=28), or as a placebo (n=38), during coronary angioplasty and stenting (percutaneous coronary intervention, PCI)AQ1. The aim of this study was to examine the long-term effects and safety of VEGF gene therapy. Patients were interviewed by telephone or with a questionnaire on their current status of health, coronary and other cardiovascular events and symptoms, working ability, exercise tolerance, other diseases, such as cancer and diabetes, as well as their personal experience of the treatment. Causes of death were clarified from hospital records. The total follow-up time was 8.1 years (range 6.9-9.7 years). Overall 82% of the patients were reached across the study. Eight (7.5%) of the patients died during the follow-up, but there was no significant difference in mortality between the groups (3/32 vs 2/26 vs 3/31 VEGF-adenovirus vs VEGF-plasmid/liposome vs placebo, respectively; P=0.88). The incidence of major adverse cardiovascular events (MACEs) (10 vs 11 vs 15; P=0.85), cancer (1 vs 4 vs 2; P=0.38) or diabetes (2 vs 2 vs 2; P=0.97) did not differ between the groups. Local intracoronary VEGF gene transfer is safe and does not increase the risk of MACE, arrhythmias, cancer, diabetes or other diseases.