Pioneering Treatments for Paroxysmal Nocturnal Hemoglobinuria

Introduction

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired blood disorder. It is characterised by chronic destruction of red blood cells and blood clots, primarily manifesting in fatigue and potentially leading to lifelong dependence on blood transfusions. The disease affects 10 to 20 people per million, primarily adults, with no association with sex, race, ethnicity, or geography. This Institute for Clinical and Economic Review (ICER) draft evidence report provides a comprehensive review of the latest research findings and treatments for PNH.

The Current State of PNH Treatment

The treatment landscape for PNH has been transformed by the advent of C5 inhibitor therapy. This treatment significantly reduces intravascular hemolysis, thrombosis, and death, bringing life expectancies closer to age-matched controls. FDA-approved intravenous C5 inhibitors, such as eculizumab and ravulizumab, are recommended for symptomatic PNH patients. Ravulizumab is often preferred due to its longer half-life and lower costs.

Pegcetacoplan – A New Hope

Pegcetacoplan, another FDA-approved treatment, has shown promise. Unlike C5 inhibitors, pegcetacoplan prevents both intra and extravascular hemolysis. However, it is largely used only for patients who have clinically significant extravascular hemolysis (EVH) while on a stable C5 inhibitor regimen.

Iptacopan and Danicopan – The Next Generation of PNH Treatments

Two first-in-class proximal complement inhibitors, Iptacopan and Danicopan, are currently under consideration for FDA approval. Iptacopan, an oral Factor B inhibitor, is being considered for all PNH patients, while Danicopan, an oral Factor D inhibitor, is being considered as an add-on therapy for treatment-experienced patients with clinically significant EVH. Both drugs display promising early trial results. However, we need more research to comprehend their long-term benefits and safety profiles fully. 

The Cost-Effectiveness of New Treatments

A recent study examined the cost-effectiveness of iptacopan and add-on danicopan in treatment-experienced patients with PNH. The study found that treatment with iptacopan resulted in small gains in quality-adjusted life years (QALYs) and equivalent life years (evLYs), and would be cost-saving compared to ravulizumab. However, treatment with add-on danicopan resulted in more costs, with an incremental cost-effectiveness ratio of $9,462,000 per QALY or evLY gained.

Conclusion

New therapies like iptacopan and danicopan are changing the treatment landscape for PNH, a rare blood disorder. We need to investigate their long-term benefits and safety profiles further. Their cost-effectiveness will depend on their price as per this ICER report.