What is Sickle Cell Disease (SCD)?

Oct. 3, 2024

The pharmaceutical giant Pfizer recently announced it would voluntarily withdraw its sickle cell disease therapy, Oxbryta, from worldwide markets, owing to the emergence of clinical data that links “fatal events” to the drug.

About Sickle Cell Disease (SCD):

It is an inherited blood disorder.
It is marked by flawed hemoglobin.
- Hemoglobin is the molecule in Red Blood Cells (RBCs) that carries oxygen to the tissues of the body.
How does it affect blood flow?
- Normally, RBCs are disc-shaped and flexible enough to move easily through the blood vessels.
- People with SCD have atypical hemoglobin molecules called hemoglobin S, which can distort RBCs into a sickle, or crescent, shape.
- These sickled RBCs do not bend or move easilyand can block blood flow to the rest of the body.
- SCD interferes with the delivery of oxygen to the tissues.
What causes it?
- The cause of SCD is a defective gene, called a sickle cell gene.
- A person will be born with SCD only if two genes are inherited—one from the mother and one from the father.
Symptoms:
- Early stage: Extreme tiredness or fussiness from anemia, painfully swollen hands and feet, and jaundice.
- Later stage: Severe pain, anemia, organ damage, and infections.
Treatments:
- A bone marrow transplant(stem cell transplant) can cure SCD.
- However, some treatments can help relieve symptoms, lessen complications, and prolong life.
- Gene therapyis also being explored as another potential cure.
- The UK recently became the first country to approve gene therapy treatment for SCD.