Evaluate the Pharmacokinetics, Safety, and Tolerability of Nirsevimab in Healthy Chinese Adults

This is a Phase 1, randomized, double-blind, placebo-controlled study to evaluate the PK, safety and tolerability, and ADA of nirsevimab when administered as a single fixed IM dosage to healthy Chinese adult subjects. Enrolment is planned at a single study center in China. Approximately 24 subjects will be randomly assigned in a 3:1 ratio to receive nirsevimab (n = 18) or placebo (n = 6). All subjects will be followed for approximately 150 days after dosing to assess safety, PK, and ADA response.

Inclusion criteria

• Age 18 to 45 years
• Weight ≥ 45 kg and ≤ 110 kg and Body Mass Index of 19 to 26 kg/m2
• Healthy Chinese subjects (both male and female)
• Normotensive
• Normal electrocardiogram (ECG) within 28 days prior to Day 1

Exclusion criteria

• Acute illness at study entry (pre-dose on Day 1)
• Fever ≥99.5°F (37.5°C) on day of dosing
• Any drug therapy within 14 days prior to Day 1 (except contraceptives).
• Receipt of immunoglobulin or blood products within 6 months prior to study entry.
• Receipt of any investigational drug therapy within 120 days prior to investigational product dosing or planned to receive any investigational drug therapy within 150 days after investigational product dosing.
• Previous receipt of any marketed or investigational mAb.
• Previous vaccination against RSV.
• History of immunodeficiency or receipt of immunosuppressive medications during the prior year.
• History of asthma.
• History of autoimmune disorder.
• Evidence of any systemic disease on physical examination.
• Evidence of infection with hepatitis A, B, or C virus, syphilis, or human immunodeficiency virus.
• Any clinically significant abnormal laboratory assessments at screening.
• Pregnant or nursing mother.
• Alcohol or drug abuse