The world’s first treatment using CRISPR therapy, a gene-editing technology, got the green light on November 16, 2023.
Casgevy, also called Exa-cel, got the approval from the U.K. Medicines and Healthcare products Regulatory Agency (MHRA) less than a week ago. It is the first-ever such approval for the particular treatment. The goal is to treat two tough blood problems: sickle cell disease and transfusion-dependent beta-thalassemia.
U.S. Food and Drug Administration (FDA) advisors gave the thumbs up for clinical use in late October. Now, all eyes are on the FDA itself, which is expected to decide on the approval by December, as reported by Live Science. MHRA’s groundbreaking approval of Casgevy might kick off a new age in gene therapy. Yet, uncertainties linger about how affordable the treatment will be and if it will be safe in the long run.
Purpose of the world’s first approved CRISPR therapy
MHRA gave the green light to Casgevy for treating sickle-cell disease (SCD) and transfusion-dependent beta-thalassemia. These are lifelong genetic issues caused by changes in the genes responsible for hemoglobin, a protein allowing red blood cells to carry oxygen in the body.
Over a hundred thousand people in the U.S. are believed to have SCD, but the numbers vary among different groups. Moreover, one of every 365 Black babies is born with SCD. This ailment alters the shape of red blood cells to a C-shape instead of the rounded form, according to Live Science.
The sickle-shaped cells die fast and stick together, clogging blood vessels. Consequently, patients develop anemia and frequently endure painful episodes known as pain crises.
🧬🧬 Gene Editing—The Time Has Come: Regulators in the U.K. have approved CRISPR Therapeutics' gene-editing treatment for two blood diseases, marking the first-ever regulatory authorization of a CRISPR-based therapy in the world
To Make Money From Gene Editing Click Here:… pic.twitter.com/R8Ydw4OSkd
— Algomasters.com (@BluePhoenixFin) November 17, 2023
Beta-thalassemia impacts roughly one in one hundred thousand individuals globally. It affects those of Mediterranean, Asian, African, and Middle Eastern backgrounds most. Those with beta-thalassemia don’t produce a sufficient amount of hemoglobin, resulting in serious anemia.
Sickle-cell anemia results from a shortage of healthy red blood cells. The illness is so severe that patients need frequent red blood cell transfusions throughout their lives, thereby rendering them “transfusion-dependent.”
How does CRISPR therapy work?
CRISPR behaves like molecular scissors, slicing genes out of DNA using an enzyme called Cas9. This enzyme is guided by a molecule of RNA to the specific DNA target. The technology borrows from a natural defense mechanism used by bacteria and simple organisms called archaea to fend off viruses.
Casgevy targets a gene known as BCL11A. This gene normally codes for a protein that manages the shift from fetal hemoglobin to the adult version shortly after birth. However, in patients with Sickle Cell Disease (SCD) and beta-thalassemia, the adult hemoglobin is flawed.
Casgevy aims to deactivate BCL11A, enabling the body to continue producing fetal hemoglobin, as the adult version is ineffective. The process involves extracting blood-forming stem cells from the patient’s bone marrow. In the lab, Casgevy is used to edit the BCL11A gene in these cells.
The modified cells, equipped with functional hemoglobin, are reintroduced into the patient’s body. Prior to reintroduction, patients are required to take a chemotherapy drug called busulfan to clear out the unedited cells remaining in their bone marrow.