Gene, cellular and pharmacogenetic therapy: AFM-Telethon uses donations to develop new therapies for the most frequent rare diseases.
What are biotherapies?
Since traditional pharmacology gives no perspective on the rare genetic diseases long considered incurable, AFM-Telethon has for many years used Telethon donations to drive the development of innovative therapies derived from recent knowledge in genetics and cellular biology: namely biotherapies.
A biotherapy is a treatment using biological drugs or biotechnological drugs. There are several different types:
- Gene therapy, which involves identifying a defective gene or reintroducing a functional gene into the body.
- Cell therapy, which involves injecting a cell or a cell patch to repair organs and restore a function.
These new therapeutic strategies pave the way for treating common diseases. Medical research is moving forward.
Gene therapy: gene-drugs
Gene therapy is one of the preferred methods for treating genetic diseases but also certain cancers. It involves inserting into the patient’s cells a normal version of a gene that is not functioning and is causing the disease. The functional gene then enables the patient to again produce the protein whose deficiency was the source of the disease.
There are three conditions for success:
- Know the gene responsible for the disease, i.e. the function of this gene, in order to be able to “repair” the cell.
- Allow the gene to reach and enter the cell using a “vector”, most frequently a virus that is rendered harmless for the patient.
- Combine the gene with a “promoter”, a small DNA sequence that lets it function once inside the cell.
A pioneer in gene therapy, AFM-Telethon has teams specialized in the design, development and production of these “drug-genes”, through its Genethon laboratory.
Cell therapy: cells to regenerate organs
Cell therapy involves grafting cells to repair or regenerate a damaged organ or tissue. Cell therapy uses three types of stem cells:
- Stem cells known as “adult” are cells that are able to regenerate, such as those of the liver, the surface of the intestines and the muscles. They help to renew tissues. They can be taken from the patient, then cultured and reinjected, without risk of rejection. However, their ability to differentiate is limited and they are quite rare and difficult to isolate and culture.
- So-called “embryonic” stem cells are found in the embryo when they are at the stage of a few cells. Easy to culture and able to proliferate infinitely, they can transform into any type of specialized cell: skin, muscle, intestine, vein, etc.
- Since 2007, induced pluripotent stem cells (IPS cells) allow us to use adult stem cells to produce stem cells with the characteristics of embryonic stem cells. Several research programs are devoted to this field.
I-Stem, AFM-Telethon laboratory dedicated to stem cells, continues its work to develop treatments for rare monogenic diseases, using stem cells.
A cell therapy clinical trial for retinitis pigmentosa - STREAM - is ongoing with the Vision Institute in Paris. A second cell therapy program - PACE - for sickle cell ulcers is in the preclinical phase. In parallel, the collaborative MyoPharm program, launched by AFM-Telethon and I-Stem, involves testing a large number of existing pharmacological molecules on cellular models of rare pathologies (high-throughput screening) to identify those that could be effective for these diseases.
Biotherapies for the most common diseases
There are many bridges between research into diseases that are sometimes very rare as well as common diseases. The biotherapies currently being tested for rare diseases may affect many other diseases in the future.
Loyal to its public interest strategy, AFM-Telethon encourages the emergence of innovative therapies that create opportunities for medicine overall.
- The first success of gene therapy for “bubble babies”, children without immune systems, helped to develop gene therapies (car-T cells) for various cancers (lymphoma, leukemia, myeloma).
- Progeria, an ultra-rare disease characterized by premature ageing, shares mechanisms with physiological ageing and ageing induced by anti-cancer chemotherapy or anti-HIV tritherapies. The therapeutic options for progeria provide perspectives that affect the entire population.
- Beta thalassemia, a rare genetic disease affecting the red blood cells, is due to the same gene as sickle-cell anemia, which affects a large proportion of the African, Afro-American, Mediterranean and Asian population. The gene therapy developed for thalassemia is today under trial for sickle-cell anemia.
- The regenerative cell therapies used experimentally for treating the cardiac disease observed in many myopathies were very quickly extended to heart failure caused by infarction.
- The cell patch developed by I-Stem in collaboration with Saint-Louis hospital in Paris, Quinze-Vingts hospital and the Vision Institute, to repair the retina in certain forms of retinitis pigmentosa, a rare disease of the vision, offers therapeutic hope for al diseases of the retina, whether they are rare and genetic, or common and related to ageing, such as age-related macular degeneration (ARMD) which affects over 1.5 million people.
- Cell therapy for the skin considered for certain genetic diseases or for skin complications of genetic diseases is applicable to the treatment of chronic skin ulcers caused by type-II diabetes and serious venous insufficiency.