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C5 Inhibitor
A C5 complement inhibitor blocks the activation of the C5 component of the complement cascade, preventing formation of the membrane attack complex and reducing inflammatory cell activation.
A C5 complement inhibitor blocks the activation of the C5 component of the complement cascade, preventing formation of the membrane attack complex and reducing inflammatory cell activation. Used for Paroxysmal nocturnal hemoglobinuria (PNH), Atypical hemolytic uremic syndrome (aHUS), Generalized myasthenia gravis (gMG).
At a glance
| Generic name | C5 Inhibitor |
|---|---|
| Sponsor | Alexion Pharmaceuticals, Inc. |
| Drug class | Complement C5 inhibitor |
| Target | C5 |
| Modality | Small molecule |
| Therapeutic area | Immunology |
| Phase | Phase 3 |
Mechanism of action
C5 inhibitors target the complement system, a key part of innate immunity. By blocking C5 cleavage, these agents prevent generation of C5a (a potent inflammatory mediator) and C5b-9 (the membrane attack complex). This reduces complement-mediated inflammation and cell lysis in diseases driven by excessive complement activation.
Approved indications
- Paroxysmal nocturnal hemoglobinuria (PNH)
- Atypical hemolytic uremic syndrome (aHUS)
- Generalized myasthenia gravis (gMG)
- C3 glomerulopathy
Common side effects
- Meningococcal infection
- Headache
- Nasopharyngitis
- Fatigue
Key clinical trials
- A Study Evaluating the Efficacy, Safety, Pharmacokinetics and Pharmacodynamics of Crovalimab in Pediatric Participants With Atypical Hemolytic Uremic Syndrome (aHUS) (PHASE3)
- A Study to Evaluate How Pozelimab + Cemdisiran Combination Therapy Works in Adult Patients With Paroxysmal Nocturnal Hemoglobinuria (PNH) Whose Current Treatment is Not Working Efficiently (PHASE3)
- Avacincaptad Pegol Open-Label Extension for Patients With Geographic Atrophy (PHASE3)
- A First-in-Human Safety and Efficacy Study of ALN-CFB, a Small Interfering RNA (siRNA) Targeting Complement Factor B, in Adult Participants With Paroxysmal Nocturnal Hemoglobinuria With Persistent Anemia on a C5 Inhibitor (PHASE1, PHASE2)
- A Long-term Safety and Efficacy Study of Danicopan as an Add-on Therapy to Complement Component 5 Inhibitor (C5i) in Participants With PNH (PHASE3)
- Study of Safety and Efficacy of HS-10542 in Patients With Paroxysmal Nocturnal Hemoglobinuria (PHASE1, PHASE2)
- Zimura Compared to Sham in Patients With Autosomal Recessive Stargardt Disease (STGD1) (PHASE2)
- A Study to Investigate OCS Tapering in Adult Participants With Generalized Myasthenia Gravis Treated With Ravulizumab (PHASE4)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- C5 Inhibitor CI brief — competitive landscape report
- C5 Inhibitor updates RSS · CI watch RSS
- Alexion Pharmaceuticals, Inc. portfolio CI