A Phase 2/3, Double-Blind, Randomized, Placebo-Controlled, Multicenter Study to Evaluate the Efficacy and Safety of Mitapivat in Subjects With Sickle Cell Disease.

This research study is investigating a new oral medication called Mitapivat for adults living with sickle cell disease (SCD). SCD is a lifelong condition that affects your red blood cells. Normally, these cells are round and flexible, but in SCD, they can become stiff and shaped like a crescent moon or 'sickle.' These sickle cells can block small blood vessels, leading to periods of pain (called sickle cell pain crises) and other health problems, including anaemia (a low number of healthy red blood cells), which can make you feel very tired.

The main purpose of this study is to see if Mitapivat can help improve your red blood cell count (measured by a substance called haemoglobin) and reduce the number of painful sickle cell crises you experience. Researchers will be looking to see if patients taking Mitapivat have a significant increase in their red blood cells over nearly a year, compared to those taking a placebo. They will also count how many painful crises people have each year.

To make sure the study gives reliable results, some participants will receive Mitapivat and others will receive a placebo – a tablet that looks identical but contains no active medicine. Neither you nor your study doctor will know which you are taking. This is called a 'double-blind' study. The study also measures other health markers like bilirubin (which can be high in SCD), reticulocytes (young red blood cells), and how your fatigue levels change, to get a full picture of the medicine's effects.