SCD: Voxelotor significantly increased hemoglobin levels and reduced markers of hemolysis

Voxelotor (Oxbryta) is the first hemoglobin oxygen-affinity modulator. It has disease-modifying potential by increasing hemoglobin levels and decreasing hemolysis indicators in sickle cell patients. It binds reversibly to hemoglobin, stabilizing the oxygenated hemoglobin state and preventing HbS polymerization by increasing hemoglobin’s affinity for oxygen.

In November 2019, the U.S. Food and Drug Administration (FDA) granted accelerated approval for (Voxelotor) Oxbryta tablets to treat SCD in adults and children 12 years and older. Following this approval, another one was secured in December 2021 as the U.S. FDA expanded the approved use of Oxbryta for treating SCD in patients four years of age and older.

The FDA approval of Oxbryta was based on evidence from one clinical trial (Trial 1/NCT03036813) that enrolled patients with SCD disease at 60 sites in the United States, Canada, Egypt, Kenya, Lebanon, Oman, Jamaica, Great Britain, Italy, Netherlands, France, and Turkey. Fifty-one percent (46/90) of patients treated with OXBRYTA achieved an increase in hemoglobin level of at least 1g/dl compared to 6.5% (6/92) of patients treated with placebo. In this trial, Voxelotor provided a significant, sustained increase in hemoglobin level and reduced the incidence of worsening anemia and hemolysis in persons with sickle cell disease.

Recently, Pfizer acquired GBT, the developer of Oxbryta. This acquisition is expected that Oxbryta will reach more SCD patients globally through leveraging Pfizer resources and in-country representation.