- ZILBRYSQ is the first and only macrocyclic peptide C5 inhibitor approved as a self-administered once-daily, subcutaneous autoinjector for adults living with generalized myasthenia gravis (gMG) in the U.S.¹

- ZILBRYSQ now offers two self-administration options for adults living with gMG who are anti-acetylcholine receptor (AChR) antibody positive.1

- The autoinjector is designed to help simplify self-administration of ZILBRYSQ, offering patients another administration option and a more convenient treatment experience.2,3

- Approval is supported by data showing ZILBRYSQ bioequivalence between the autoinjector and the existing prefilled syringe, with complete dose delivery achieved for 99.8% (n=449*) of autoinjector administrations. Patients reported high satisfaction with self-injection of ZILBRYSQ using the autoinjector device.2

ATLANTA, Oct. 20, 2026 /PRNewswire/ -- UCB (Euronext Brussels: UCB), a global biopharmaceutical company, today announced that the U.S. Food and Drug Administration (FDA) has approved the first self-administered once-daily autoinjector administration option for the treatment of generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) antibody positive with ZILBRYSQ® (zilucoplan).¹ The autoinjector is designed to help simplify self-administration of ZILBRYSQ, offering patients another administration option and a more convenient treatment experience.2,3

"This approval is the answer to a question on which we've been relentlessly focused: How do we continue to improve an already effective therapy for daily use?" said Kimberly Moran, PhD, SVP & Head, U.S. Rare Diseases at UCB. "As the first treatment to be approved as a once-daily autoinjector option for adults living with gMG in the U.S., ZILBRYSQ now provides the same therapy via another administration option. At UCB, we are committed to science and make it our point to continually help improve how people experience it."

The ZILBRYSQ autoinjector is designed to automatically deliver a pre-defined dose when activated against the skin.1,2 Prior to the autoinjector's approval, ZILBRYSQ was available as a self-administered prefilled syringe (PFS). Patients or their care partners will now have another portable treatment solution.

"For a chronic condition like gMG, having different administration options allows patients to choose the approach that best fits their individual preferences and routines," said Donatello Crocetta, Global Head of Medical Affairs and Chief Medical Officer at UCB. "From a medical standpoint, it was essential to confirm that this added administrative option didn't come at the expense of safety and efficacy. The data supporting the autoinjector's complete dose delivery show that this option continues to offer an effective treatment for patients."

The approval of the ZILBRYSQ autoinjector for self-administration is supported by data from the following studies:

- DV0012 – a Phase 1, open-label, single-center, two-period crossover study in healthy adult volunteers (n=14) which established bioequivalence of ZILBRYSQ delivered via an autoinjector compared with a PFS.2

- DV0013 – a Phase 3b open-label, multi-center study in adult patients (n=31) with gMG self-administering ZILBRYSQ via autoinjector once daily. Complete dose delivery was achieved for 99.8% (n=449*) of autoinjector administrations. Patients reported high satisfaction with self-injection of ZILBRYSQ using the autoinjector device.2 Self-administration was generally well tolerated. The most common TEAE was injection-site pain (n=3; 9.7%).2

- A human factors validation study of 100 participants† demonstrating that 90% successfully completed an injection with the ZILBRYSQ autoinjector on their first attempt without training.4

UCB expects the autoinjector to be available commercially in Q1 2027.

*Total autoinjectors used and returned.

†Participants defined as patients with gMG or those exhibiting ocular symptoms (injection-experienced and injection-naïve); caregivers (injection-experienced and injection-naïve); and healthcare professionals (HCPs).

About ZILBRYSQ® (zilucoplan)

ZILBRYSQ (a synthetic macrocyclic peptide) is a once-daily, self-administered, subcutaneous injection that works by blocking complement component 5 (C5), a protein involved in the immune-mediated damage that occurs at the neuromuscular junction in gMG.1,5 ZILBRYSQ is indicated for the treatment of generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) antibody positive.¹

The precise mechanism through which ZILBRYSQ exerts therapeutic effects in gMG is unknown.

In addition to ZILBRYSQ, UCB's gMG portfolio includes RYSTIGGO® (rozanolixizumab-noli), a subcutaneously infused monoclonal antibody targeting the neonatal Fc receptor (FcRn) approved by the FDA for the treatment of generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) or anti-muscle-specific tyrosine kinase (MuSK) antibody positive.6 With two approved medicines with distinct mechanisms of action, UCB continues to offer physicians and the U.S. gMG community a choice of targeted therapies from a single company.

The precise mechanism through which RYSTIGGO exerts therapeutic effects in gMG is unknown.

About generalized myasthenia gravis (gMG)

gMG is a rare neuromuscular autoimmune disease that has a global prevalence of 150–350 cases per 1 million people.7 People living with gMG can experience a variety of symptoms, including severe muscle weakness that can result in double vision, drooping eyelids, difficulty with swallowing, chewing and talking, as well as life-threatening weakness of the muscles of respiration.8,9

In gMG, pathogenic autoantibodies can impair synaptic transmission at the neuromuscular junction (NMJ) by targeting specific proteins on the post-synaptic membrane.10 This disrupts the ability of the nerves to stimulate the skeletal muscle and results in a weaker contraction.10 gMG can occur in any race, gender or age.8,9,11

Important Safety Information about ZILBRYSQ® (zilucoplan) in the U.S.1

ZILBRYSQ is a complement inhibitor indicated for the treatment of generalized myasthenia gravis (gMG) in adult patients who are anti-acetylcholine receptor (AChR) antibody positive.

IMPORTANT SAFETY INFORMATION INCLUDING BOXED WARNING

WARNING: SERIOUS MENINGOCOCCAL INFECTIONS

Life-threatening and fatal meningococcal infections have occurred in patients treated with complement inhibitors. These infections may become rapidly life-threatening or fatal if not recognized and treated early. ZILBRYSQ, a complement inhibitor, increases the risk of serious infections caused by Neisseria meningitidis.

- Complete or update meningococcal vaccination (for serogroups A, C, W, Y, and B) at least 2 weeks prior to the first dose of ZILBRYSQ, unless the risk of delaying therapy outweigh the risks of developing a meningococcal infection. Comply with the most current Advisory Committee on Immunization Practices (ACIP) recommendations for vaccination against meningococcal bacteria in patients receiving a complement inhibitor.

- Persons receiving ZILBRYSQ are at increased risk for invasive disease caused by Neisseria meningitidis, even if they develop antibodies following vaccination. Monitor patients for signs of serious meningococcal infections and evaluate immediately if infection is suspected.

Because of the risk of serious meningococcal infections, ZILBRYSQ is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called ZILBRYSQ REMS.

CONTRAINDICATIONS

ZILBRYSQ is contraindicated for initiation in patients with unresolved Neisseria meningitidis infection.

WARNINGS AND PRECAUTIONS

Serious Meningococcal Infections

ZILBRYSQ, a complement inhibitor, increases a patient's susceptibility to serious, life-threatening, or fatal infections caused by meningococcal bacteria (septicemia and/or meningitis) in any serogroup, including non-groupable strains. Life-threatening and fatal meningococcal infections have occurred in both vaccinated and unvaccinated patients treated with complement inhibitors. The initiation of ZILBRYSQ treatment is contraindicated in patients with unresolved serious Neisseria meningitidis infection. Complete or update meningococcal vaccination (for serogroups A, C, W, Y and B) at least 2 weeks prior to administering the first dose of ZILBRYSQ, according to current ACIP recommendations for patients receiving a complement inhibitor. If urgent ZILBRYSQ therapy is indicated in a patient who is not up to date with meningococcal vaccines according to ACIP recommendations, provide the patient with antibacterial drug prophylaxis and administer meningococcal vaccines as soon as possible. Closely monitor patients for early signs and symptoms of meningococcal infection and evaluate patients immediately if infection is suspected. Consider interruption of ZILBRYSQ in patients who are undergoing treatment for serious meningococcal infection, depending on the risks of interrupting treatment in the disease being treated.

ZILBRYSQ REMS 

Due to the risk of meningococcal infections, ZILBRYSQ is available only through a restricted program under a REMS called ZILBRYSQ REMS. Under the ZILBRYSQ REMS, prescribers must enroll in the program. Prescribers must counsel patients about the risk of meningococcal infection, provide the patients with the REMS educational materials, and ensure patients are vaccinated with meningococcal vaccines. Additional information on the REMS requirements is available at www.ZILBRYSQREMS.com or 1-877-414-8353.

Other Infections

Serious infections with Neisseria species (other than Neisseria meningitidis), including disseminated gonococcal infections, have been reported in patients treated with complement inhibitors.