The United Kingdom has become the first country to officially approve a gene therapy treatment for sickle cell disease and thalassemia.

The regulatory agency in Britain has approved the first-ever gene therapy for sickle cell disease, potentially providing relief to numerous individuals suffering from this debilitating condition in the United Kingdom.

On Thursday, the Medicines and Healthcare Regulatory Agency announced that they have granted approval for Casgevy, the first medication to be licensed using the CRISPR gene editing tool. This tool was recognized with a Nobel prize in 2020.

The treatment for sickle cell disease and thalassemia has been approved by the agency for patients who are 12 years and older. Casgevy, created by Vertex Pharmaceuticals (Europe) Ltd. and CRISPR Therapeutics, is the approved treatment. So far, bone marrow transplants have been the only long-term solution, but they are a difficult procedure with unpleasant side effects.

Dr. Helen O’Neill from University College London stated that CRISPR-based technology (gene-editing) holds the key to revolutionary cures that will transform lives in the future.

According to a statement, the term “cure” has not been applicable to sickle cell disease or thalassemia in the past. However, with the MHRA’s approval of gene therapy, this is seen as a significant moment in history.

Sickle cell disease and thalassemia are both the result of genetic errors in the hemoglobin-carrying genes, which are responsible for carrying oxygen in red blood cells.

Individuals with sickle cell disease, which is prevalent among those of African or Caribbean descent, experience a genetic alteration that results in their red blood cells becoming crescent-shaped. This can lead to obstruction of blood flow and severe symptoms such as intense pain, organ damage, stroke, and other complications.

Individuals with thalassemia may experience intense anemia due to a genetic mutation, necessitating frequent blood transfusions and ongoing treatment with injections and medications throughout their lifetime. This condition is most commonly found in individuals of South Asian, Southeast Asian, and Middle Eastern descent.

The recently developed medication, Casgevy, functions by focusing on the troublesome gene found in a person’s bone marrow stem cells, allowing for the production of functional hemoglobin. Medical professionals extract stem cells from the patient’s bone marrow and utilize genetic editing methods in a controlled environment to repair the gene. The cells are then reintroduced into the patient’s body for a long-term cure.

The UK’s governing body announced that its approval of the gene therapy for sickle cell disease was supported by a research study conducted on 29 individuals. Out of these, 28 did not experience any significant pain for a period of at least one year after receiving treatment. Similarly, in the thalassemia study, 39 out of 42 patients who underwent the therapy did not require a red blood cell transfusion for at least one year following treatment.

Gene therapy treatments typically cost thousands of dollars and experts have previously raised concerns that they could remain out of reach for the people most in need of treatment. Vertex Pharmaceuticals said they had not yet established a price for the treatment in Britain and were working with health authorities “to secure reimbursement and access for eligible patients as quickly as possible.”

The British government requires a watchdog’s recommendation before making medicines and treatments accessible to patients in the national healthcare system.

The U.S. Food and Drug Administration is currently reviewing Casgevy and is expected to make a decision in the coming month. They will then consider another gene therapy for sickle cell.

Sickle cell disease affects millions of individuals globally, with approximately 100,000 cases in the United States. It is more prevalent in regions where malaria is or was prevalent, such as Africa and India, and is also more common among specific ethnicities, including those of African, Middle Eastern, and Indian descent. According to researchers, carrying the sickle cell trait may provide protection against severe malaria.


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