When to Stop Eculizumab in Complement-Mediated Thrombotic Microangiopathies

Area of Science:

• Nephrology
• Hematology
• Immunology

Background:

• Eculizumab, a terminal complement inhibitor, has transformed atypical hemolytic uremic syndrome (aHUS) management.
• It also shows promise for secondary HUS (sHUS) from various causes, including drug toxicity and transplantation.
• Despite efficacy, eculizumab's cost and administration present challenges.

Purpose of the Study:

• To review existing literature on discontinuing eculizumab in aHUS and sHUS.
• To provide guidance for clinicians considering eculizumab cessation in these conditions.
• To inform patient management strategies regarding long-term eculizumab therapy.

Main Methods:

• Systematic review of published literature.
• Evaluation of studies reporting eculizumab cessation in patients with aHUS and sHUS.
• Analysis of reported relapse rates and clinical outcomes post-cessation.

Main Results:

• Relapse rates after stopping eculizumab in aHUS can be as high as 30%.
• Relapse is infrequent in patients with sHUS after eculizumab cessation.
• These findings suggest different therapeutic approaches for aHUS versus sHUS.

Conclusions:

• Indefinite eculizumab therapy may be reasonable for aHUS patients, with close monitoring if therapy is stopped.
• Short courses of eculizumab are generally justified for sHUS, given the low risk of relapse.
• Clinical decision-making regarding eculizumab cessation should be tailored to the specific HUS subtype.