Zilucoplan

also known as: Zilbrysq, RA101495

A self-injectable complement inhibitor — a synthetic macrocyclic peptide that blocks C5 complement activation, FDA-approved for generalized myasthenia gravis as a daily subcutaneous injection.

A 15-amino-acid synthetic macrocyclic peptide conjugated to a polyethylene glycol tail, binding complement C5 to prevent cleavage into C5a and C5b and subsequent membrane attack complex (MAC) formation.

Mechanism of action

Binds complement component C5 with high affinity, preventing its cleavage by C5 convertases into C5a (anaphylatoxin) and C5b (initiator of MAC assembly). By blocking terminal complement activation, reduces antibody-mediated destruction of the neuromuscular junction in MG. Unlike eculizumab (monoclonal antibody), zilucoplan is a peptide allowing SC self-administration.

Primary uses

Generalized myasthenia gravis (AChR antibody-positive)
Complement-mediated disease research

Typical dosing

0.3 mg/kg once daily (subcutaneous (self-injection))

Meningococcal vaccination required at least 2 weeks before starting. Supplied as pre-filled syringes.

Regulatory status

FDA-approved in 2023 (Zilbrysq, UCB) for generalized myasthenia gravis in anti-acetylcholine receptor antibody-positive adults. First subcutaneous complement inhibitor.

References

[clinical-trial] Howard JF, et al. "Zilucoplan in patients with generalized myasthenia gravis (RAISE): a randomised, double-blind, placebo-controlled, phase 3 study." Lancet Neurol, 2023;22:395-406.
[fda-pi] Zilbrysq (zilucoplan) Prescribing Information. UCB.

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Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.