The main objective of this study is to assess the safety, tolerability, pharmacokinetics, and immunogenicity of single ascending doses of ABBV-701 in healthy adult western and Asian participants.

Inclusion Criteria:

• Body weight is ≥ 35 kg and BMI is ≥ 18.0 to ≤ 32.0 kg/m2 after rounding to the tenth's decimal.
• A condition of general good health, based upon the results of a medical history, physical examination, vital signs, laboratory profile, and a 12-lead ECG
• Part 2 and Part 4 only:

For Japanese Participants:

--Participant must be first or second-generation Japanese parentage (both parents of Japanese descent), residing outside of Japan. Participants must be in general good health and maintain a typical Japanese lifestyle, including consuming a typical Japanese diet.

Han Chinese Participants:

--Participant must be first or second-generation Han Chinese of full Chinese parentage (both parents of Han Chinese descent), residing outside of China. Participants must be in general good health and maintain a typical Chinese lifestyle, including consuming a typical Chinese diet.

Exclusion Criteria:

• History of any clinically significant cardiovascular, respiratory (except mild asthma as a child), renal, endocrine, hepatic, gastrointestinal, hematologic, or psychiatric disease or disorder, or any uncontrolled medical illness.
• History of any clinically significant sensitivity or allergy to any medication or food.