New FDA-Approved C3 Glomerulopathy (C3G) Treatment Targets Underlying Cause of Disease

Carla Nester, MD, Professor of Pediatrics-Nephrology at the University of Iowa, discusses the recent U.S. Food and Drug Administration (FDA) approval of iptacopan as the first and only treatment of adults with C3 glomerulopathy (C3G).

C3G is a rare kidney disease characterized by damage to kidney glomeruli due to abnormal activation of the complement system. When C3 proteins get lodged in the kidney, glomeruli get injured and buildup of toxins and reduced urine production occur. This can ultimately lead to declined kidney function. Common signs and symptoms include:

Hematuria
Proteinuria
Reduced glomerular filtration rate and increased creatinine levels
Fatigue
Edema of the hands, feet, and ankles

Iptacopan is an oral inhibitor of the alternative complement pathway that targets the underlying cause of C3G. It is the first approved treatment for C3G. This approval follows positive data from the APPEAR-C3G clinical trial.

The APPEAR-C3G clinical trial was a phase 3, multicenter, randomized, double-blind, parallel group, placebo-controlled study evaluating the safety and efficacy of twice-daily oral iptacopan in patients with C3G. The study included a 6-month randomized, double-blind treatment period with iptacopan compared to placebo and was followed by an additional 6-month, open-label treatment period where all participants received iptacopan. The primary endpoint of the first period was proteinuria reduction from baseline at 6 months compared to placebo, measured by 24-hour urine protein-creatinine ratio.

Results observed in the study included a clinically meaningful reduction in proteinuria with iptacopan. This reduction was seen as early as 14 days into treatment and was sustained at 12 months. In the open-label period, proteinuria reduction was also seen in participants who had switched from placebo to iptacopan.

Additionally, a favorable safety profile was observed. The most common adverse reactions included nasopharyngitis and viral infections.

Chapters:
Introduction 00:00
C3G Overview 00:37
Fabhalta Overview 2:12
APPEAR-C3G Clinical Trial 4:19
Take Home Message 6:55
Treatment Safety 8:08