FDA Approves Zilucoplan Autoinjector for Myasthenia Gravis

The FDA has approved a once-daily, self-administered autoinjector for zilucoplan (Zilbrysq; UCB), giving adults with generalized myasthenia gravis (gMG) who are anti-acetylcholine receptor (AChR) antibody positive a second way to take the complement component 5 (C5) inhibitor at home, according to a news release from UCB. The macrocyclic peptide was previously available only as a prefilled syringe; UCB expects the autoinjector to be commercially available in the first quarter of 2027.¹

For pharmacists, the approval adds a device choice to a therapy that already involves daily injections, weight-based dosing, and a Risk Evaluation and Mitigation Strategy (REMS). According to UCB, the autoinjector is designed to automatically deliver a predefined dose when activated against the skin.¹

Bioequivalence and Dose Delivery Data

The approval is supported by 2 studies presented at the American Academy of Neurology (AAN) 2026 Annual Meeting. In DV0012, a phase 1, open-label, single-center, 2-period crossover study, 14 healthy adult volunteers received a single subcutaneous injection with each device in randomized order. The ratios of geometric least-squares means for the autoinjector versus the prefilled syringe were 0.98 (90% CI, 0.95-1.01) for area under the curve (AUC), 0.98 (90% CI, 0.95-1.01) for AUC up to the last quantifiable concentration, and 1.00 (90% CI, 0.96-1.04) for maximum observed concentration, establishing bioequivalence.²

DV0013, a phase 3b, open-label, multicenter study, enrolled 31 patients with gMG enrolled in the RAISE-XT extension study or receiving commercial zilucoplan. Patients self-administered the drug once daily with the autoinjector, and the primary objective was effective self-administration through day 14, defined as investigator-confirmed complete dose delivery. Complete dose delivery was achieved for 99.8% (95% CI, 98.8-100) of autoinjectors; UCB reported that figure reflects 449 autoinjectors used and returned.^1,2

Treatment-emergent adverse events (TEAEs) occurred in 22.6% of patients (7 of 31), and all were mild and nonserious. Injection-site pain was the most common TEAE, reported in 3 patients (9.7%). At day 14, the median score on the satisfaction with self-injection domain of the Self-Injection Assessment Questionnaire, which ranges from 0 to 10, was 8.9 (range, 6-10).^1,2

UCB also cited a human factors validation study of 100 participants, including patients with gMG or ocular symptoms, caregivers, and health care professionals, in which 90% completed an injection with the autoinjector on their first attempt without training.¹

Counseling and Dispensing Considerations

The device does not change zilucoplan's safety profile. The drug carries a boxed warning for serious meningococcal infections, and patients must complete or update vaccination against serogroups A, C, W, Y, and B at least 2 weeks before the first dose unless the risks of delaying therapy outweigh the risk of infection. Patients remain at increased risk even if they develop antibodies after vaccination. Under the REMS program, pharmacies that dispense the drug must be certified and must verify that prescribers are certified, and patients must carry a Patient Safety Card during treatment and for 2 months after stopping it.³

Dosing is based on actual body weight: 16.6 mg once daily for patients weighing less than 56 kg, 23 mg for 56 kg to less than 77 kg, and 32.4 mg for 77 kg or more. Patients who miss a dose should inject it as soon as possible, then resume their regular schedule without taking more than 1 dose per day. Because pancreatitis and pancreatic cysts have been reported, baseline lipase and amylase levels are recommended before treatment starts, and patients should be counseled on their increased susceptibility to other encapsulated bacteria, including Streptococcus pneumoniae and Neisseria gonorrhoeae.³

A Second Self-Injection Option

Zilucoplan received initial US approval in 2023 based on a 12-week, randomized, placebo-controlled study in which it significantly improved Myasthenia Gravis Activities of Daily Living total scores versus placebo (least-squares mean difference, -2.09; 95% CI, -3.24 to -0.95; P < .001).³

gMG is a rare autoimmune neuromuscular disease with a global prevalence of 150 to 350 cases per 1 million people, and symptoms can include double vision, drooping eyelids, difficulty swallowing, chewing, and talking, and life-threatening weakness of the respiratory muscles.¹

REFERENCES

1. UCB announces U.S. FDA approval for ZILBRYSQ (zilucoplan) autoinjector self-administration for adults living with generalized myasthenia gravis. News release. UCB. October 16, 2026. Accessed October 16, 2026. https://www.ucb.com/newsroom/press-releases/article/ucb-announces-us-fda-approval-for-zilbrysqr-zilucoplan-autoinjector-self-administration-for-adults-living-with-generalized-myasthenia-gravis

2. Petrulis M. Bioequivalence and effectiveness of auto-injector-delivered, self-administered zilucoplan compared with pre-filled syringe. Poster presented at: American Academy of Neurology Annual Meeting; April 18-22, 2026; Chicago, IL. Poster P11-9-009.

3. Zilbrysq (zilucoplan) injection. Prescribing information. UCB, Inc.; revised January 2026. Accessed October 16, 2026. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/216834s013lbl.pdf