NCT07415252

SkyVaricella® (NBP608) Vaccine With Lower Potencies in Healthy Children Aged 12 Months to 12 Years

A Phase III, Randomized, Double-blinded, Active-controlled, Multinational, Multicenter Study to Assess the Safety and Immunogenicity of a Two-dose Regimen of SKYVaricella® (NBP608) in Children Aged 12 Months to 12 Years

• Status: Not Yet Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 780 (estimated)
• Sponsor: SK Bioscience Co., Ltd. · Industry
• Sex: All
• Age: 12 Months – 12 Years
• Healthy volunteers: Accepted

Summary

The goal of this study is to evaluate the safety and immunogenicity of an investigational varicella vaccine in children. Researchers will compare the investigational vaccine, NBP608, with licensed varicella vaccines. The study includes children aged 12 months to 12 years. Approximately 780 participants will take part in this study. Participants will be randomly assigned to receive either the investigational vaccine (NBP608) or licensed varicella vaccines. Some participants will receive two doses, while others will receive one dose, according to the assigned study group. Participants will: Receive two subcutaneous injections of a study vaccine, administered approximately three months apart (if applicable). Visit the study clinic seven times over approximately 15 months. Receive follow-up phone calls 7 days after each vaccination to monitor for safety.

Detailed description

This is a Phase III, randomized, Double-blinded, Active-controlled, Multinational, Multicenter study designed to evaluate the safety and immunogenicity of a two-dose regimen of NBP608 in children aged 12 months to 12 years. Approximately 780 participants will be enrolled in this multinational, multicenter, randomized study and assigned in a 4:4:4:1 ratio to four groups: two investigational vaccine groups (NBP608 mid-potency and low-potency) and two active control groups (licensed varicella vaccines, Varivax® and SKYVaricella®). Each of the NBP608 groups and Active Control Group 1 (Varivax®) will include approximately 240 participants, while Active Control Group 2 (SKYVaricella®) will include approximately 60 participants. Within each group, participants will be further randomized in a 3:1 ratio to receive either two doses or one dose of the assigned study vaccine. Immunogenicity will be assessed using blood samples collected at predefined time points to evaluate immune responses to varicella. Safety will be evaluated throughout the study by monitoring adverse events (AEs), serious adverse events (SAEs), and adverse events of special interest (AESIs) following vaccination. Each participant will take part in the study for approximately 15 months, including scheduled clinic visits and follow-up assessments. The overall study duration will depend on enrollment progress and completion of follow-up across all participating countries.

Conditions

• Varicella (Chickenpox)

Interventions

Type	Name	Description
BIOLOGICAL	NBP608 (Mid Potency)	NBP608 (mid potency) is a live attenuated varicella virus vaccine (Oka/SK strain). It is supplied as a lyophilized single-dose vial with a separate diluent and administered as a 0.5 mL subcutaneous injection. Each dose contains ≥2,400 PFU after reconstitution.
BIOLOGICAL	NBP608 (Low Potency)	NBP608 (low potency) is a live attenuated varicella virus vaccine (Oka/SK strain). It is supplied as a lyophilized single-dose vial with a separate diluent and administered as a 0.5 mL subcutaneous injection. Each dose contains ≥2,400 PFU after reconstitution.
BIOLOGICAL	Varivax®	Varivax® is a licensed live attenuated varicella virus vaccine (Oka/Merck strain). It is supplied as a lyophilized single-dose vial with a separate diluent and administered as a 0.5 mL subcutaneous injection. Each dose contains ≥1,350 PFU after reconstitution.
BIOLOGICAL	SKYVaricella®	SKYVaricella® is a licensed live attenuated varicella virus vaccine (Oka/SK strain). It is supplied as a lyophilized single-dose vial with a separate diluent and administered as a 0.5 mL subcutaneous injection. Each dose contains ≥2,400 PFU after reconstitution.
OTHER	Normal Saline (Placebo)	Placebo consisting of normal saline (0.9% sodium chloride solution), administered as a 0.5 mL subcutaneous injection.

Timeline

• Start date: 2026-06-05
• Primary completion: 2027-02-13
• Completion: 2028-01-02
• First posted: 2026-02-17
• Last updated: 2026-02-17