This study will be a Phase I, First-In-Human (FIH), randomised, single-blind, placebo-controlled, single ascending dose (SAD), sequential group study in healthy male and female participants of non- childbearing potential performed at a single study centre.~The study consists of 3 parts:~Part A: SAD (up to 5 dose levels) of AZD9550 administered subcutaneous (SC) in healthy participants.~Part B: 1 dose level of AZD9550 administered SC in healthy participants of Japanese descent.~Part C: 1 dose level of AZD9550 administered intravenous (IV) in healthy participants.~The study will comprise of:~A Screening Period of maximum 28 days.~A Treatment Period during which participants will be resident at the Clinical Unit from 2 days before (Day -2) investigational medicinal product (IMP]) administration (Day 1) until at least 7 days (168 hours; Day 8) after IMP administration.~Weekly out-clinic visits on Days 15, 22, 29, and 36.~A Follow-up Visit 6 weeks (Day 43) after the IMP dose.
This is a Phase I Randomised Single-blind Placebo-controlled Study to Assess the Safety, Tolerability, and Pharmacokinetics of AZD9550 Following Single Ascending Dose Administration to Healthy Participants.