FDA Approves Zilbrysq (Zilucoplan) Autoinjector, a New Administration Option for a Macrocyclic Peptide

On October 16, 2026, UCB announced that the FDA approved an autoinjector administration option for Zilbrysq (zilucoplan) for adults with generalized myasthenia gravis who are anti-acetylcholine receptor antibody positive. No FDA press announcement was found for this action, so the account rests on the sponsor's announcement, with some United States trade coverage dated October 20 to 21, 2026.

Zilucoplan is a macrocyclic peptide complement C5 inhibitor. It was first approved in 2023 as a prefilled syringe presentation, and the October 2026 action adds a second administration option.

The scope of the approval needs to be stated plainly. This is a delivery-device approval for an existing drug, not a new drug approval and not a new indication. The labeled use did not expand with this action.

For a peptide-focused blog, the event still matters as a regulatory milestone for a macrocyclic peptide product. A new presentation of an approved peptide completing FDA review is a different kind of action from a first approval, and this post records it as such.

As with every FDA approval, the decision applies to the specific product, Zilbrysq, and the specific indication on its label. It does not extend to compounded formulations, research compounds, or any other use of zilucoplan. This post gives no instructions for using the device or the drug.