AstraZeneca's rare disease add-on therapy Voydeya scores FDA nod

With AstraZeneca’s dominance in the rare blood disease paroxysmal nocturnal hemoglobinuria (PNH) threatened by the recent approval of the first pill on the market for the condition, Novartis’ Fabhalta, AstraZeneca has answered in the United States for its add-on oral treatment in the indication.

The FDA has signed off on Voydeya (danicopan), a factor D inhibitor, to treat PNH patients with extravascular hemolysis (EVH), a condition that causes red blood cell destruction outside of the blood vessels. The nod comes three months after the Japanese Ministry of Health, Labour and Welfare (JHLW) became the first regulator worldwide to endorse the therapy.

Voydeya works as an add-on for AZ’s pair of PNH standard-of-care blockbusters—Soliris, which has been on the market for 17 years and generated $3.2 billion in sales in 2023, and its follow-on Ultomiris, which was approved in 2018 and accounted for $3 billion in sales last year.

AZ said that 10% to 20% of those who use C5 inhibitors such as Soliris and Ultomiris develop EVH, which results in a continuance of anemia symptoms and can require transfusions.  

“The approval of Voydeya offers this small subset of PNH patients an add-on therapy designed to address EVH, while maintaining disease control with Ultomiris or Soliris,” Bart Scott, M.D., a professor at the Fred Hutchinson Cancer Center, said in a release.

In the ALPHA phase 3 trial, Voydeya improved hemoglobin levels from baseline to week 12 and met secondary endpoints, including transfusion avoidance.

Long-term follow-up data from the study, which the company presented four months ago, showed that the improvements in mean hemoglobin levels and absolute reticulocyte count levels held up through 48 weeks. Additionally, after 12 weeks, 83% of patients didn’t need a blood transfusion. Through 24 weeks, 78% of patients could say the same.

AZ gained the drug in its 2021 acquisition of Alexion for $39 billion. Two years earlier, Alexion picked up the drug in $930 million buyout of another Connecticut company, Achillion.

In February, Europe's regulator recommended Voydeya for approval. AZ also is investigating danicopan as a treatment for the macular degeneration condition geographic atrophy.

In addition to having a convenience edge as an oral treatment over the infused C5 inhibitors, Novartis’ factor B inhibitor Fabhalta may have an advantage in preventing red blood cell destruction as it works upstream of the C5 terminal pathway.

Another new competitor in PNH is Appelis’ C3 inhibitor Empaveli which targets a different enzyme than AZ’s treatments. Empavelli generated sales of $91 million in 2023, which was its second full year on the market.