It may have missed out on the highest accolade of the Nobel Prize this year, but there is no doubt that the genetic engineering technology CRISPR is set to end the year on a high as it announces the launch of its first clinical trial for the cure of a genetic disease. Last week Crispr Therapeutics, the biotech company based between Switzerland and Massachusetts and led by French microbiologist Emmanuelle Charpentier, announced its application to EU health regulators for permission to commence a trial to cure beta thalassemia which is a blood disorder, as well as an application to the US Food and Drug Administration for the trial of a drug curing sickle cell disease.
Both beta thalassemia and sickle cell disease are caused by a mutation in a gene known as HBB, responsible for the creation of beta-globin, which binds oxygen and delivers it throughout the body via red blood cells. People suffering from this mutation usually develop symptoms leading to anemia, heightened rates of infection and severe pain. The gene therapy developed by Crispr Therapeutics aims to cure both these diseases with the same method; drawing blood from the patient, scientists will separate out the stem cells that create red blood cells, inject them with electricity and then introduce Crispr edited components that allow for the production of fetal hemoglobin. Fetal hemoglobin is something we all possess during infancy, the element that passes oxygen from mother to fetus, but after six months of development our bodies halt the production of fetal hemoglobin and move on to adult hemoglobin, hence where the mutation arises. Once scientists have injected the edited cells, any mutated or diseased cells are removed by a process of either radiation or a high dosage of chemotherapy drugs. Within a week the new cells will make their way to the patient’s bone marrow and begin producing red blood cells with fetal hemoglobin.
Speaking with Wired, Crispr Therapeutics CEO Sam Kulkarni said of the new therapy, “I think it’s a momentous occasion for us, but also for the field in general. Just three years ago we were talking about CRISPR-based treatments as sci-fi fantasy, but here we are.” Although the study of this therapy reports promising results, with a 40 percent boost in the expression of fetal hemoglobin and zero negative effects across the 6,000 studied sites in the genome, this is the first genetic disease to receive CRISPR treatment. Earlier this year we spoke with geneticist Adam Rutherford, who voiced concerns about the confidence placed in CRISPR in what is an extremely tentative and experimental field; “These are significant studies and they are a step in this direction, but even so, these are still very experimental, they are poorly understood, and they are not really correcting the disease at all; we are talking about a bundle of cells in which a small proportion of the disease gene has been corrected.”
If both the European regulators and the FDA approve, these trials could begin as early as the beginning of 2018.