The goal of this clinical trial is to compare two different presentations (vial and syringe versus autoinjector) of navenibart in healthy adult volunteers. The main questions it aims to answer are:

• Do these presentations lead to similar drug concentrations in the blood?
• Do these presentations lead to similar safety and tolerability?

Researchers will compare the drug concentrations and safety profile of each group to determine if they are similar.

Participants will:

• Receive one dose of navenibart with either the vial and syringe or the autoinjector.
• Stay in the clinic beginning one day prior to dosing through 2 days after dosing.
• Return to the clinic for approximately 9 additional non-residential visits.
• Complete medical and other testing, including blood draws.

Key Inclusion Criteria:

• Males and females 18 to 55 years of age
• In good health, as determined by the Investigator
• Written informed consent, including confirmation of willingness to comply with all trial procedures
• Body weight between 50 and 100 kg, and body mass index (BMI) between 18 and 30 kg/m^2
• Has not previously received navenibart
• Not pregnant or breastfeeding and agreement to comply with requirements for pregnancy and breastfeeding, contraception use, and egg donation for the specified periods.

Key Exclusion Criteria:

• Prior or ongoing medical history, or results of a medical assessment, that the Investigator feels could result in a risk to the safety of the participant or the quality of data from the trial.
• Key laboratory results outside of defined ranges
• History or positive test results for tobacco, nicotine products, alcohol, marijuana (cannabis), or drugs of abuse
• Receipt of other prohibited medications, biologic medications, or investigational products within defined windows prior to dosing
• History of severe allergic reactions with an unknown cause
• Donation of blood (at least 500 mL), or any amount of platelets or plasma within defined windows prior to dosing.
• Known hypersensitivity to any component of navenibart
• Any condition that the Investigator feels may affect the ability to provide written informed consent or demonstrates unwillingness or inability to comply with trial procedures