A Study to Assess the Safety and Pharmacokinetics of Single Ascending Subcutaneous and Intravenous Doses of DS-2325a in Healthy Subjects

Inclusion Criteria: * Participants must give written informed consent to participation in the study prior to Screening * Healthy men and women 18 to 45 years of age (inclusive), with a BMI of 18 kg/m2 to 30 kg/m\^2 (inclusive) at Screening * All women must have a negative serum pregnancy test at Screening and all women of childbearing potential must have a negative urine pregnancy test on Day -1 * Women must not be lactating during the study treatment period and for 3 months after the last dose of study treatment * Women of childbearing potential must practice effective contraception during the study treatment period and for 3 months after the last dose of study treatment. They must agree to use 2 different means of nonhormonal contraceptive methods * Women of non-childbearing potential must be either surgically sterile (ie, bilateral tubal ligation at least 3 months prior to dosing) or in menopausal state confirmed as follows: 1 year of spontaneous amenorrhea without an alternative medical cause and a serum FSH level ≥40 mIU/mL * Men must agree to use contraception (condom with spermicide) during the study treatment period and for at least 3 months after the last dose of study treatment or be surgically sterile (vasectomy at least 3 months prior to dosing) * Women should not donate eggs and men should not donate sperm during the study treatment period and for at least 3 months after the last dose of study treatment * Participants must be in good health as determined by Scre…