Positives

• In a compassionate-use cohort of severe COVID-19 patients with respiratory distress, those receiving terminal complement blockade had higher 15-day estimated survival (82.9% vs 62.2%) and laboratory evidence of reduced inflammation MDPI.
  
  
• A forum member with suspected complement-driven Long COVID and microclots noted that complement deposits have been documented on endothelial cells and platelets, providing a biological rationale she found persuasive for trying C5 blockade Phoenix Rising.
  
  

Negatives

• A patient described intermittent headache, nausea, and fatigue after each two-week infusion, with the post-infusion crash lasting a day or two WebMD.
  
  
• Several users reported recurrent meningococcal vaccination requirements and persistent worry about meningococcal infection because of how deeply terminal complement is suppressed Healthline.
  
  

Hurdles & Side Effects

• A forum participant flagged the roughly $500,000 per-patient annual price tag as the single largest barrier to off-label use in ME/CFS or Long COVID Phoenix Rising.
  
  
• A patient described the every-two-week infusion schedule and required pre-treatment meningococcal vaccination cycle as exhausting to keep up with while already housebound NIH.