Ultomiris (ravulizumab) and Soliris (eculizumab), both developed by global biopharmaceutical leader AstraZeneca, are both effective treatments for paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS). Yet this efficacy is occasionally disrupted by extravascular hemolysis. Hemolysis refers to the destruction of red blood cells. In extravascular hemolysis, red blood cells are destroyed outside of your blood vessels. This can lead to hemolytic anemia and symptoms like fatigue, pale skin, shortness of breath, and heart palpitations.
An estimated 10-20% of people living with PNH deal with extravascular hemolysis while on Ultomiris and Soliris. These individuals often require additional interventions, such as blood transfusions, to manage their symptoms.
According to Nick Paul Taylor in Biospace, AstraZeneca has been working to overcome these challenges while developing danicopan. This orally administered complement inhibitor reversibly binds to factor D to prevent alternative pathway-mediated hemolysis. It performed well in a Phase 3 clinical study which showed that danicopan improved hemoglobin levels and reduced hemolysis over a 12–48-week period.
The U.S. Food and Drug Administration (FDA) recently approved danicopan – which will be marked as Voydeya – as an add-on treatment for Soliris and Ultomiris for adults living with PNH. If you have PNH and are interested in learning more about Voydeya, please speak with your physicians for more information.
About Paroxysmal Nocturnal Hemoglobinuria (PNH)
Paroxysmal nocturnal hemoglobinuria is a rare and acquired hematopoietic stem cell (HSC) disorder that affects red and white blood cells, as well as platelets. In PNH, a mutation in the PIGA gene leads to the absence of glycosylphosphatidylinositol (GPI)-anchored proteins on the surface of blood cells. This is particularly apparent on red blood cells. Normally, these proteins protect blood cells from the immune system. At the same time, the gene mutation causes the body to create rapidly multiplying PNH cells. The immune system begins destroying healthy blood cells, leading to hemolytic anemia, while the PNH cells survive. The lack of proteins on white cells and platelets can also lead to increased susceptibility to infections and issues with blood clotting. Up to 30% of PNH cases result from aplastic anemia treatment.
PNH varies in severity. Some individuals with mild cases can survive for decades following diagnoses, while the average lifespan is around 10 years following diagnosis. The median age for diagnosis is 30s. Signs of PNH may include:
- Dark or blood-colored urine
- Sexual dysfunction (in males)
- Headache
- Dysphagia (difficulty swallowing)
- Pale skin
- Excessive bruising and bleeding
- Abdominal pain and contractions
- Fatigue
- Esophageal spasms
- Rapid heartrate
- Chest pain
- Difficulty breathing
- Kidney disease
In addition to Ultomiris and Soliris, PNH may be treated with thrombolytic therapies, anticoagulation drugs, folic acid supplements, prednisone, and bone marrow transplantation.