Eculizumab and ravulizumab are common treatments for PNH. Both drugs are C5 inhibitors, so called because they block the activity of an immune system protein called C5.
This helps to prevent the breakdown of red blood cells inside blood vessels, yet despite this, some patients experience ongoing anaemia. This has spurred the search for alternative treatments, and in this 2024 study, R. Peffault de Latour and colleagues described the combined results from two clinical trials, which tested the effectiveness of a new drug called iptacopan.
In total, around 100 patients took part. Some had previously tried a C5 inhibitor. Others hadn’t. No matter, iptacopan worked well. Levels of a marker called lactate dehydrogenase (LDH) returned to normal, indicating that red blood cells were not being destroyed. Flagging haemoglobin levels rallied, anaemia was avoided and patients felt less fatigued. Over the 24 weeks they were followed, very few patients needed a red blood cell transfusion.
Iptacopan works in a different way to eculizumab and ravulizumab. Although it also targets an immune system protein, it’s a different one, called factor B. Iptacopan helps to control the breakdown of red blood cells inside blood vessels, and also to reign in the premature destruction of red blood cells in the liver and spleen. Iptacopan was licensed for use in the UK in late 2024. It is given as a tablet that is taken twice per day.