The building, a few tens of meters from the premises of the Généthon, which gave birth to it, develops innovative treatments, those which have already begun to transform medicine. An almost revolutionary production: because it is not a question here of a simple combination of chemical molecules, but of life therapy, which consists in introducing genetic material into cells to treat a disease.

Since its emergence twenty years ago, gene therapy has taken all sorts of forms. It can eliminate or repair an altered gene directly in a patient’s cell, or use genetically modified viruses to kill cancer cells. It can even arm immune cells of small research heads against cancer cells, before reinjecting them into patients: this is “CAR-T” technology.

It is still necessary to be able to meet the needs of this ultra-sharp production. For this, Yposkesi, which means promise in Greek, was officially created in 2016, under the impetus of Genethon.

“We began to engage in the field of bioproduction in 2006, telling ourselves that a production tool was needed: otherwise there would be no clinical trials, and therefore no access to drugs for patients. “, explains Frédéric Revah, the general manager of Généthon, the laboratory financed by the Telethon.

“At that time, there was nothing to produce,” he recalls, as the approach was so new. “But we had to set up this platform for our independence,” he adds.

– Risk culture –

The Généthon bioproduction building, before becoming that of Yposkesi, was created in 2013, becoming for a few years the largest site in the world for gene therapy.

From now on, Yposkesi is developing, on behalf of biotechs or large pharmaceutical laboratories, so-called clinical batches, which will be used for human trials.

But Yposkesi has not finished growing: on the other side of the street, a new building, which has cost nearly 60 million euros, is in full construction. From the end of 2023, it will employ 80 people, and will produce commercial batches of gene therapy, ready to be placed on the market.

On paper, the principle seems, if not simple, at least intelligible: it involves replacing dysfunctional genes. In reality, the process is extremely complex. We will have to use viruses that have been transformed to become vectors, equipped with the necessary equipment to modify the patient’s cell.

“In the best case, the production of these treatments takes three, four months. Sometimes much more, especially in the event of yield problems”, explains Alain Lamproye, the general manager of Yposkesi.

The approach is difficult, but promising, with 17 drugs registered worldwide for gene therapy. At the end of 2021, some 2,000 products were in development for this therapy. These new treatments are expensive, sometimes up to 2 million dollars like Zolgensma, a treatment for spinal muscular atrophy whose technology comes from… Genethon research.

In this context, to allow its expansion, Yposkesi passed last year under the control of the South Korean group SK. The H-MRB holding, bringing together AFM-Téléthon, Généthon and the Center for Stem Cell Studies, now has 25% of the capital, against 54% previously, and Bpifrance’s share has fallen from 46% to 5% .

“It is not for lack of having sought in France and Europe”, underlines Frédéric Revah.

Despite the Covid, and the questions of health sovereignty raised by the pandemic, would Europe still remain too little present on innovative therapies? Genethon recently joined the American consortium Bespoke Gene Therapy, dedicated to accelerating the development of gene therapies for ultra-rare diseases.

“The attractiveness remains less than in the United States, like the culture of risk”, laments Laurence Tiennot-Herment, the president of the AFM-Téléthon.