The purpose of the study is to investigate the safety, tolerability, and pharmacokinetic parameters of 2 dose strengths of donzakimig, each administered subcutaneously as a single dose, in healthy Chinese and Japanese study participants.

Inclusion criteria

• Study participant must be 18 to 55 years of age inclusive at the time of signing the informed consent form (ICF)
• Study participant who is overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and cardiac assessment
• Chinese study participant who is of Chinese descent as evidenced in appearance and verbal confirmation of familial heritage and is of Chinese descent with all 4 grandparents, OR Japanese study participant who is of Japanese descent as evidenced in appearance and verbal confirmation of familial heritage and is of Japanese descent with all 4 grandparents
• Study participant has a body mass index within the range of 18 to 30kg/m2 (inclusive)
• Study participant can be male or female

Exclusion criteria

• Study participant has clinically significant multiple or severe drug allergies (including to humanized monoclonal antibodyies (mAbs), intolerance to topical corticosteroids, severe post-treatment hypersensitivity reactions (including, but not limited to, erythema multiforme major, linear immunoglobulin A dermatosis, toxic epidermal necrolysis, and exfoliative dermatitis), known relevant allergy (not including mild seasonal hay fever and/or conjunctivitis or low grade food intolerances), pre-existing history of a relevant allergic condition, or a predisposition for an allergic reaction, as judged by the Investigator
• Study participant has a recent history (within 6 months prior to Screening) or currently active clinically-significant bacterial, fungal, endoparasite (including the presence of ova, cysts, or parasites detected in stool sample provided at Screening), or viral (including hospitalization for coronavirus disease 2019 [COVID-19]) infection, as judged by the Investigator
• Study participant has a history of inflammatory bowel disease (eg, Crohn's disease or ulcerative colitis)
• Study participant has a history of diabetes
• Study participant has received any vaccination within 8 weeks for live vaccines (including attenuated) and 4 weeks for nonlive vaccines prior to the Baseline Visit or is anticipated to do so within 60 days after the dose of IMP
• Study participant has received Bacillus Calmette-Guerin vaccinations within 1 year prior to the Baseline Visit or will receive them within 90 days after the dose of IMP
• Study participant has participated in another study of an IMP or has received any biologic agent within the 30 days prior to Screening (or 5 half-lives, whichever is longer)
• Study participant has had a positive human immunodeficiency virus (HIV) antibody test
• Study participant has the presence of either hepatitis B core antibody or hepatitis B surface antigen at Screening or within 3 months prior to dosing
• Study participant has a positive hepatitis C antibody test result at Screening or within 3 months prior to Screening.
• Study participant has a positive hepatitis C ribonucleic acid (RNA) test result at Screening or within 3 months prior to Screening

Due to the small sample size in this trial, IPD cannot be adequately anonymized i.e., there is a reasonable likelihood that individual participants could be re-identified. For this reason, data from this trial cannot be shared.