Handok's new treatment for paroxysmal nocturnal hemoglobinuria (PNH), Empaveli Injection (pegcetacoplan), has won approval in Korea.

The Ministry of Food and Drug Safety (MFDS) approved Empaveli on Monday. In Korea, the approved indication is PNH in adults.

Empaveli inhibits hemolysis in and around blood vessels by binding to complement proteins C3 and C3b, which are part of the body's innate immune system. This suppresses the complement chain reaction.

AstraZeneca's Soliris (eculizumab) and Ultomiris (ravulizumab), already approved in Korea, complement C5 inhibitors, which differ in their mechanism of action. Unlike Soliris and Ultomiris, which are intravenous formulations, Empaveli is injected subcutaneously.

According to the domestic marketing authorization, patients switching from a C5 inhibitor to Empaveli should receive 1,080 mg of Empaveli twice weekly in addition to their existing C5 inhibitor therapeutic dose for the first four weeks to minimize the risk of hemolysis due to abrupt drug discontinuation. After four weeks, the C5 inhibitor should be discontinued before injecting Empaveli alone.

PNH is caused by an inherited mutation in the X-chromosome that makes red blood cells sensitive to the complement response, resulting in intravascular and extravascular hemolysis. Clinically, it manifests as aplastic anemia with decreased hematopoietic stem cells. Other symptoms include fatigue, jaundice due to chronic hemolysis, hepatosplenomegaly, hemolytic anemia, hematopoietic deficiency, and venous thrombosis.

"We expect the approval of Empaveli to help expand treatment options for adult patients with paroxysmal nocturnal hemoglobinuria," MFDS said. "We will continue to do our best to quickly review and approve treatments that have sufficiently confirmed safety and effectiveness based on our regulatory science expertise to expand patient treatment opportunities."