This is a Phase 1/1b, multicenter, randomized, placebo-controlled, double-blind study to evaluate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of single and multiple doses of DNL921 in healthy participants and participants with Alzheimer's disease (AD). The principal aim of this study is to obtain safety and tolerability data. This information, together with PK and PD data, will inform dose selection and design of future studies.
Are male or female of non-childbearing potential and are aged 18 through 60 years at the time of screening
Have a BMI of 18 through 32 kg/m2 and a body weight of at least 50 kg
For female participants: Are of non-childbearing potential
For male participants: Are surgically sterile by bilateral orchidectomy, or are abstinent, or agree to use two acceptable forms of contraception
Have any history of clinically significant neurological, psychiatric, endocrine, pulmonary, cardiovascular, gastrointestinal, hepatic, pancreatic, renal, metabolic, hematological, immunological, or allergic disease, or other major disorders
Have a positive serum pregnancy test or are currently lactating or breastfeeding
Have been hospitalized during the 4 weeks prior to screening
Are male or female of non-childbearing potential and aged 50 to 75 years at the time of screening