UK MHRA approves Oxbryta for hemolytic anemia due to sickle cell disease

Voxelotor, an oral treatment taken once daily, is the first medicine authorized in Great Britain that directly inhibits sickle hemoglobin (HbS) polymerization, the molecular basis of sickling and destruction of red blood cells in SCD.

The marketing authorization by the MHRA, which follows the European Commission (EC) authorization earlier this year, is based on results demonstrating clinically meaningful and statistically significant improvements in hemoglobin (Hb) levels, accompanied by a reduction of hemolysis markers, for patients treated with voxelotor. Data from the Phase III HOPE (Hemoglobin Oxygen Affinity Modulation to Inhibit HbS Polymerization) Study of 274 patients 12 years of age and older with SCD showed that, after 24 weeks of treatment, 51.1% of patients receiving voxelotor achieved a greater than 1 g/dL increase in Hb compared with 6.5% receiving placebo (p<0.001), with significant improvements in markers of hemolysis in indirect bilirubin and reticulocyte percentage.

In the HOPE Study, the most common adverse reactions occurring in at least 10% of patients treated with Oxbryta with a difference of >3% compared to placebo were headache (26% vs. 22%), diarrhea (20% vs. 10%), abdominal pain (19% vs. 13%), nausea (17% vs. 10%), fatigue (14% vs. 10%), rash (14% vs. 10%) and pyrexia (12% vs. 7%). Results from the HOPE Study were published in June 2019 in The New England Journal of Medicine and the analysis of the complete data from the HOPE Study was published in The Lancet Haematology in April 2021. The EC decision was granted in February 2022.