Reyoung (suzhou) Biology Science & Technology Co Ltd

Phase Ib: Main objectives: 1. To evaluate the safety and tolerability of a single intramuscular injection of RB0026 injection. Secondary objectives: 1. To evaluate the pharmacokinetic (PK) characteristics of a single intramuscular injection of RB0026 injection; 2. To evaluate the pharmacodynamic (PD) characteristics of a single intramuscular injection of RB0026 injection; 3. To evaluate the immunogenicity of a single intramuscular injection of RB0026 injection. Phase II: Main objectives: 1. To evaluate the reduction of the incidence of RSV-induced LRTI requiring medical intervention within 150 days after administration of RB0026 injection in infants entering their first RSV epidemic season. Secondary objectives: 1. To evaluate the effect of RB0026 injection on reducing the incidence of RSV-induced hospitalization within 150 days after administration; 2. To evaluate the safety and tolerability of a single intramuscular injection of RB0026 injection; 3. To evaluate the PK characteristics of a single intramuscular injection of RB0026 injection; 4. To evaluate the PD characteristics of a single intramuscular injection of RB0026 injection; 5. To evaluate the immunogenicity of a single intramuscular injection of RB0026 injection. Exploratory objectives: 1. To describe the characteristics of resistance to RB0026 injection by genotypic and phenotypic analysis; To evaluate the effect of RB0026 injection on reducing the incidence of RSV-induced LRTI requiring medical intervention within 151-360 days after administration.

Primary purpose: To evaluate the tolerability and safety of RB0026 injection after intramuscular or intravenous injection in healthy subjects; Secondary purpose: To study the pharmacokinetics of RB0026 injection after intramuscular or intravenous injection in healthy subjects; To study the RSV neutralizing activity (pharmacological efficacy study) of RB0026 injection after intramuscular or intravenous injection in healthy subjects; To evaluate the immunogenicity of RB0026.

(1) Determine the maximum tolerated dose (MTD) and/or determine the recommended dose for subsequent studies of RB0004 injection; (2) Evaluate the safety and tolerability of RB0004 injection in patients with solid tumors.