PegcetacoplanComplement C3 inhibitor
Pegcetacoplan blocks complement protein C3. Systemic treatment for complement-mediated blood disease and injection into the eye involve different products, exposures and outcomes that should not be merged.
What is Pegcetacoplan?
Pegcetacoplan is a complement C3 inhibitor used in different formulations for very different conditions. Systemic treatment for paroxysmal nocturnal haemoglobinuria (PNH) and injection into the eye for geographic atrophy require separate evidence and safety information. 1 2
How it works
It inhibits C3, an upstream component of the complement immune pathway. The consequence depends on the disease and on where the medicine is delivered. 2
Effects studied
PNH anaemia
PEGASUS studied haemoglobin outcomes in people with persistent anaemia despite C5-inhibitor treatment.
Evidence: Randomised PNH trial in a defined previously treated population. 1
Geographic atrophy
The eye-treatment question concerns slowing atrophy progression, not restoring lost sight.
Evidence: Route- and formulation-specific evidence; systemic PNH findings cannot answer this question.
What does the evidence show?
Systemic PNH trial; separate ocular-product context
Blocking an earlier point in complement
Complement is a chain of immune proteins that helps defend against infection but can also damage the body’s own cells. Pegcetacoplan acts at C3, upstream of some other complement medicines. Where the drug is delivered determines which tissues receive meaningful exposure.
The blood-disease evidence
PEGASUS examined pegcetacoplan in people with paroxysmal nocturnal haemoglobinuria, or PNH, who had persistent anaemia despite C5-inhibitor treatment. It assessed haemoglobin and other disease outcomes in that selected population. The findings cannot be treated as a general comparison for everyone with anaemia. 1
Why eye treatment is a separate story
An intravitreal preparation is injected into the eye and has been studied for geographic atrophy, an advanced form of age-related macular degeneration. Slowing an area of retinal damage is a different outcome from restoring lost vision. Neither the PNH results nor systemic safety rates can simply be transferred to that setting.
The risks follow the route
Systemic complement inhibition raises concerns about serious infections, including those caused by encapsulated bacteria. Injection into the eye carries separate risks related to the procedure and the eye itself. Current labels and indications need to be checked for each product; the shared ingredient does not make the evidence or precautions interchangeable. 2
Safety & status
Systemic complement inhibition raises the risk of serious infections, including those caused by encapsulated bacteria. Intravitreal treatment has separate eye-injection risks. 2
Country and product status
Product indications and availability vary by country; current EU and Swiss status has not been independently checked for this draft.
Frequently asked questions
Are the eye and systemic medicines interchangeable?
No. Delivery, indication and safety instructions are different.
Does slowing geographic atrophy restore vision?
No. Slower tissue-loss progression and recovery of lost vision are distinct outcomes.
Further reading
Sources
This entry was rewritten from our research archive. References below are reading leads unless a completed check is explicitly noted; a full independent evidence and regulatory review is still pending.
- Retained paper reference Archive research lead · Retained archive reference; not independently checked for this draft
- Retained source reference Archive research lead · Retained archive reference; not independently checked for this draft
Research provenance
This name was discovered in the Superpower peptide index, archived 26 October 2026. Its ratings and reviewer attribution have not been adopted as our own. The archive informed this original editorial draft; independent source review is still pending.