Gene therapy could replace amputation


In January, the International Symposium on Endovascular Therapy (ISET) celebrated 15 years of innovation in education. More than 1,100 cardiologists, interventional radiologists, vascular surgeons and other vascular specialists from around the world attended to see more than 200 research presentations and 27 live cases given over five days.

At the meeting, a team from the Jobst Vascular Center, Toledo, Ohio, stated the results of the first Phase I trial to assess the effect of a genetically engineered angiogenic growth factor in people with severe circulatory problems in the legs. The treatment was found to be safe and the study also showed the procedure produced some evidence of improved circulation: less pain, improved ulcer healing and enhanced blood pressure in the extremities

“The Phase I trial shows that injecting a genetically engineered growth factor in legs of people with severely blocked blood vessels does not cause serious adverse effects, and early evidence is giving us hope that this may work,”said Anthony Comerota, Director of the Jobst Vascular Center. “These people had less pain, their ulcers healed faster and their blood pressure was better after treatment.

51 patients with unreconstructable peripheral arterial occlusive disease with rest pain or tissue necrosis underwent treatment with intramuscular naked plasmid DNA encoding for fibroblast growth factor type 1 (NV1FGF), injected into the ischaemic thigh and calf.

Sixty-six serious adverse events were reported, none considered to be related to NV1FGF. Four patients had adverse events that were possibly or probably related to the study treatment: injection site pain, pain, peripheral oedema, myasthenia, and paresthesia.

No severe adverse events were associated with administration of NV1FGF. Two deaths remote from the treatment were not considered related.

“Many of the patients who were studied in the trial had ulcers on their feet that had been there for a long time,”said Comerota.”Many patients were in constant pain. After treatment with NV1FGF, their pain diminished, their ulcers healed and the blood pressure in their ankles increased.”The mean pain level declined significantly between 8 and 24 weeks after treatment. NV1FGF is well tolerated and potentially could be effective for the treatment of patients with end-stage ischaemia

The significant reduction in pain and aggregate ulcer size was associated with an increased transcutaneous oxygen pressure as compared with baseline pre-treatment values. A significant increase in ankle brachial index was also seen.

In summary, Comerota said: “We have assured the safety of the treatment; therefore we are moving into the second phase of the clinical evaluation, which is to objectively test this against a placebo. We are looking at pure efficacy by comparing different doses of NV1FGF in gene treatment to placebo.

The physicians are now enrolling 70 patients in a phase II efficacy trial that will compare the effectiveness of growth factor against placebo.