This study aims to find out how much adimanebart gets into the blood circulation of healthy adults. Researchers will measure the amount of adimanebart in blood over time to learn how it moves through the body. The drug's safety will also be assessed.

The participants will be assigned to one of 3 parts of the study: part 1 investigates the absolute bioavailability; part 2 investigates the effect of different body weights on adimanebart in blood after subcutaneous (SC) dosing; part 3 investigates formulation adaptations.

Participants will be in the study for approximately up to 24 weeks.

Inclusion Criteria:

• Is at least the local legal age of consent and aged 18 to 65 years, inclusive, when signing the ICF.
• Has a body weight between 60 and 100 kg and a BMI between 18.5 and 30 kg/m2, inclusive, at screening and on day -1 for part 1 and part 3, or has a body weight <60 kg or between 100 and 130 kg and a BMI between 18.5 and 38.0 kg/m2, inclusive, at screening and on day -1 for part 2.
• Discontinues and refrains from using all medications, including nonprescription and prescription medications, for ≥2 weeks before IMP administration, except for hormonal contraceptives and hormone replacement therapy in female participants. The occasional use of acetaminophen or ibuprofen is allowed.

Exclusion Criteria:

• Has any current or past clinically meaningful medical or psychiatric condition, including severe hypersensitivity reactions to drugs and/or food that, in the investigator's opinion, would confound the study results or put the participant at undue risk.
• Previously participated in an adimanebart clinical study and received at least 1 dose of IMP.
• Is currently participating in another interventional clinical study, or has received an IMP in another clinical study within 12 weeks or 5 half-lives (whichever is longer) before screening.