Rare Daily Staff

Alexion Pharmaceuticals said that the pivotal late-stage study of ALXN1210, the company’s experimental long-acting successor to its blockbuster Soliris in complement inhibitor treatment-naïve patients with paroxysmal nocturnal hemoglobinuria or PNH, an ultra-rare and life-threatening blood disorder.

PNH is a chronic and progressive condition characterized by an uncontrolled activation of the complement system, a component of the body’s immune system. It causes the destruction of red blood cells, which in result in progressive anemia, fatigue, dark urine, and shortness of breath. The condition can lead to the formation of blood clots, which can damage vital organs and cause premature death.

Like Soliris, ALXN1210 works by inhibiting the complement system, but it has the advantage of being dosed every eight weeks compared to every two weeks for Soliris.

The study demonstrated that ALXN1210 was not inferior to Soliris based on the co-primary endpoints of transfusion avoidance and normalization of lactate dehydrogenase levels, a direct marker of complement-mediated hemolysis in PNH. The study also demonstrated non-inferiority on all four key secondary endpoints including measures of quality of life and stabilized hemoglobin levels.

ALXN1210, however, did not achieve superiority in the study.

ALXN1210 was generally well tolerated with a safety profile that is consistent with that seen for Soliris.

“We are very pleased with these positive data for ALXN1210 in the first and only head-to-head study versus Soliris, and the results reinforce our ambition to establish ALXN1210 as the new standard of care for patients with PNH,” said John Orloff, executive vice president and head of research & development at Alexion. “The data are also consistent with our hypothesis that immediate, complete, and sustained C5 inhibition is critical for patients with this potentially life-threatening disease.”

Alexion expects to submit ALXN1210 for regulatory approval for PNH in the United States, European Union, and Japan in the second half of 2018.

“Having a new treatment option that achieves transfusion avoidance and provides rapid and sustained normalization of LDH levels when administered six times a year could be a meaningful improvement for patients with PNH who currently need 26 infusions per year,” said Jong Wook Lee, professor of internal medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, Korea, and an investigator in the ALXN1210 study.

ALXN1210 has received Orphan Drug designation for the treatment of patients with PNH in the United States and European Union, and for the subcutaneous treatment of patients with aHUS in the United States.

May 8, 2018
Photo: John Orloff, executive vice president and head of research & development at Alexion