Casgevy : Gene Therapy For Sickle Cell Disease And Thalassaemia
The UK Drug Regulator sanctioned a gene therapy called Casgevy heralded as a significant breakthrough for treating sickle cell disease and thalassaemia.
- Notably, this marks the world’s inaugural licensed therapy leveraging the CRISPR-Cas9 gene editing technology that earned its innovators a Nobel Prize in Chemistry 2020.
- Both sickle cell disease and thalassaemia are caused by errors in the gene for haemoglobin(Hb), a protein in the red blood cells that carry oxygen to organs and tissues.
- The therapy uses the patient’s own blood stem cells, which are precisely edited using CRISPR-Cas9.
- A gene called BCL11A, which is crucial for switching from foetal to adult haemoglobin, is targeted by the therapy.
- Foetal haemoglobin, which is naturally present in everyone at birth, does not carry the same abnormalities as adult haemoglobin.
- The therapy uses the body’s own mechanisms to start producing more of this foetal haemoglobin, alleviating the symptoms of the two conditions.
- Casgevy involves a single treatment wherein blood stem cells are extracted via apheresis and then edited over approximately six months before being reintroduced into the patient.
- Apheresis is a medical procedure that involves removing specific components from blood and returning the rest to the body.