A Phase 1 Study to Evaluate the Safety, Tolerability, PK/PD of SRSD107 in Healthy Participants

Inclusion Criteria:

• Body mass index between 18.0 and 32.0 kg/m2, inclusive.

• In good health, based on no clinically significant findings from medical history, 12lead ECG, vital signs measurements, and clinical laboratory evaluations.

• Activated partial thromboplastin time and PT within the normal range.

• Females will not be pregnant or lactating, and females of childbearing potential andmales will agree to use contraception.

• Able to understand and willing to sign an ICF and to abide by the studyrestrictions.

Exclusion Criteria:

• Significant history or clinical manifestation of any metabolic, allergic,dermatological, hepatic, renal, hematological, pulmonary, cardiovascular,gastrointestinal, neurological, respiratory, endocrine, or psychiatric disorder, asdetermined by the investigator (or designee).

• History or evidence of any abnormal bleeding or coagulation disorder; or evidence ofcoagulopathy, prolonged or unexplained, clinically significant bleeding, or frequentunexplained bruising or thrombus formation; or a history of spontaneous bleeding.

• Evidence of an active or suspected cancer, or a history of malignancy, within 5years prior to screening. Nonmelanoma skin cancer, curatively treated localizedprostate cancer, or other carcinoma in situ are not exclusionary, providing thatthey did not require systemic therapy and are considered cured.

• Acute of febrile illness within 7 days prior to dose administration or evidence ofactive infection.

• Any major surgery within 3 months prior to screening or plan to have any surgeryduring the study.

• History of clinically significant hypersensitivity, intolerance, or allergy to anydrug compound, oligonucleotide, GalNAc, food, or other substance, as determined bythe investigator (or designee).

• Confirmed systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg.

• QT interval corrected for heart rate using Fridericia's method (QTcF) >450 ms inmales or >470 ms in females confirmed by repeat measurement.

• White blood cell count <3.5 × 109/L, platelets <100 × 109/L, or hemoglobin below thelower limit of normal.

• Alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase,alkaline phosphatase, or total bilirubin >1.5 × the upper limit of normal (ULN).

• Estimated glomerular filtration rate <80 mL/min/1.73m2, as calculated by the 2021Chronic Kidney Disease Epidemiology Collaboration equation.

• Positive hepatitis panel and/or positive human immunodeficiency virus test.

• Positive pregnancy test at screening or check in.

• Receipt of blood products within 2 months prior to check in.

• Loss of >500 mL whole blood or donation of blood products within 1 month prior toscreening.

• History of intolerance to SC injections, or scarring (eg, from surgical proceduresor burns) in areas when SC dose administration may occur.

• Participants who, in the opinion of the investigator (or designee), should notparticipate in this study.