HQ Team
July 30, 2025: The US Food and Drug Administration has approved Apellis Pharmaceuticals, Inc.’s medicine for treating two rare and serious kidney diseases.
The drug pegcetacoplan, also known as Empaveli, is intended to treat C3 glomerulopathy (C3G) and primary immune-complex membranoproliferative glomerulonephritis (IC-MPGN) in individuals aged 12 and older.
The two diseases occur because a part of the immune system, known as the complement system, becomes overactive by mistake. This causes harmful immune materials to accumulate in tiny filters in the kidneys (called glomeruli), leading to kidney damage and inflammation.
Over time, about half of the people with these diseases develop kidney failure within 5 to 10 years, as their kidneys stop working well enough and they might need a transplant or lifelong dialysis. Even after a kidney transplant, the disease often comes back and can damage the new kidney.
68% drop in protein
The drug, the first approved specifically for these diseases in both adults and children, works by slowing down the overactive part of the immune system, helping to reduce kidney damage.
The diseases are estimated to affect 5,000 people in the US and up to 8,000 in Europe.
A clinical study tested Empaveli in 124 patients aged 12 or older who had these diseases but hadn’t had a transplant, or whose disease returned after a transplant.
They received the medicine or a placebo twice a week under the skin for about six months. The study showed that those treated with Empaveli had a 68% drop in the amount of protein in their urine—a sign of kidney damage—compared to those who got the placebo.
“The primary efficacy endpoint assessed the percentage change in proteinuria after six months of treatment. At 26 weeks, there was a 68% reduction in proteinuria from baseline in the Empaveli group compared to placebo. In addition, over the 26 weeks of treatment, Empaveli reduced the loss of kidney function compared to placebo,” according to an emailed FDA statement.
Serious infections
However, Empaveli has some risks. It can increase the chance of serious infections caused by certain bacteria. People must be up-to-date on vaccines against these bacteria before starting treatment, and doctors will observe for signs of infection.
Due to these risks, Empaveli is only available under a special safety program under a Risk Evaluation and Mitigation Strategy, the FDA stated.
Common side effects include reactions where the medicine is injected, fever, cold-like symptoms, flu, cough, and nausea.
Empaveli was first approved in 2021 for another rare blood disorder, and now it has been approved for these two rare kidney diseases that mostly affect children and young adults.
‘Pivotal moment’
While other treatments may focus on controlling inflammation or symptoms, Empaveli’s targeted complement inhibition offers a new approach aimed at disease modification, potentially slowing progression to kidney failure.
“With the standard of care, patients living with these rare and severe diseases frequently progress to kidney failure, necessitating lifelong dialysis and/or a kidney transplant,” said Carla Nester, MD, MSA, FASN, lead principal investigator.
“Given the urgent need, particularly in children, the approval of Empaveli marks a pivotal moment in the treatment of rare kidney diseases,” said Carla, who is also a professor of internal medicine and paediatrics and director of pediatric nephrology at the University of Iowa Stead Family Children’s Hospital.
