This pathology mouth the arteries of the legs

Is this the return of gene therapy François Meyer believes. This specialist in cell biology, which operates more than 20 years in the world of biotechnology, recently led a test that calls into light a technique conceptually very attractive, but who has experienced many setbacks over the past 20 years. "We have confirmed the feasibility and efficacy of gene therapy in a particular indication." It's even more interesting that it is for a disease for which there is no satisfactory therapeutic solution. "It is a very serious illness: severe Arteritis, or critical ischemia of lower limbs (ICMI).

This pathology mouth the arteries of the legs. Member leading them a seriously. Surgical Revascularization techniques are limited and result in a risk of mortality in the order of 30. Hence the idea to restore blood flow by injecting growth factors responsible for the production of new blood vessels. Two hormones identified a decade can play this role of the process of angiogenesis Activator: ("vascular endothelial growth factor") VEGF and FGF ("fibroblast growth factor"). These biochemical messengers naturally secreted by the body today are part of the very promising array of biologics for targeted action. The first is already used in a new generation of anticancer starving them and destroy tumors. The second has been used in gene therapy clinical trial whose results were presented in a recent medical Congress (ACC in Atlanta).

This test, called the "Talisman", focused on 107 people with a critical form of ICMI (51 benefited from treatment and 56 received a placebo). The technique is relatively simple: it is injected into muscle a solution containing plasmids including gene giving the order to the cells generate blood vessels (see diagram). After a few weeks, these instructions are followed to the letter by the cellular machinery. With néo-vaisseaux develop and muscle, new irrigated, is a part of its capacity. The test was carried out in six European countries: Germany (33 patients), Italy (29), France (25), Switzerland (20) United Kingdom (11), Belgium (7), by specialized teams.

"Save the legs".

For these patients, selected according to criteria excluding certain contraindications (Burger, cancer, retinopathy disease), it was in fact the solution of last resort before amputation. For the former Director General, the subsidiary of Aventis specializing in gene therapy Centelion, this test of phase 2 is the indisputable benefits: a reduction of 30 of cases of amputation and mortality decreased compared to placebo.

The selected protocol includes four sessions of injection of naked plasmid at two week intervals. According to Professor Jean-Noël Fiessinger, head of vascular medicine at European hospital Georges - Pompidou (HEGP), gene therapy applied to these diseases is "a very promising technique on the horizon of five years." Sanofi-Aventis, now owner of the technology, plans to launch a follow-up study of phase 3 year next to confirm these early results. Critical ischemia leads to a total of 150,000 amputations a year in the United States and about 135.000 66.500 annually in five major European countries. The cost of each of these surgeries heavy and very disabling is included between 10,000 and 20,000 euros per patient.

In the meantime, the situation becomes critical for many patients. "Increased the population of patients at high risk." "Lack of diagnosis, we see happen too late of the sick for which we can do practically anything, because we are dealing with cases of irreversible gangrènes" indicates Jean-Noël Fiessinger. With his colleague of the HEGP Marc Sapoval, head of cardiovascular radiology, this specialist launched last week a solemn appeal entitled: "save the legs". Goal: educate the medical world to the management of these diseases in the lower limbs.

Three risk factors increase the incidence of critical ischemia in developed countries: the ageing of the population, poorly supported diabetes and chronic dialysis. The progress of the angioplasty can sometimes revasculariser tissue, but these remedial techniques are not controlled everywhere. "Too often deciding an amputation to relieve pain, without arterial stock Imaging." "This screening is essential," confirms Marc Sapoval. In some cases, mechanical uses techniques similar to those used in Cardiology (balloons, stents) may restore the blood flow and save the Member. "The sick suffering from ICMI must be referred to specialty hospitals." "In some homes the situation is dramatic," said Jean-Noël Fiessinger.