Evaluation of the safety and immunogenicity of a 9-valent human papillomavirus vaccine produced in

Background: It is challenging to secure the tertiary structure of virus-like particles (VLPs) during manufacturing process development. In this study, we evaluated the safety and immunogenicity of PV-001, a 9-valent human papillomavirus (HPV) vaccine candidate manufactured in Methods: The 9-valent vaccine formulation contained L1 VLPs for HPV types 6, 11, 16, 18, 31, 33, 45, 52, and 58. A double-blind, randomized clinical trial was conducted in which participants were assigned in a 1:1 ratio to receive either the investigation vaccine or a placebo consisting solely of aluminum phosphate (AP) gel, used as an adjuvant. A total of 41 healthy women aged 19-45 years were enrolled in South Korea and administered the assigned intervention via intramuscular injection at 0, 2, and 6 months. Safety assessments included immediate adverse events (AEs), solicited local and systemic AEs, and unsolicited AEs. Immunogenicity was evaluated by measuring serum anti-HPV L1 VLP IgG and neutralizing antibody titers pre- and post-vaccination (ClinicalTrials.gov: NCT07081334). Findings: No serious adverse events (AEs) were reported following administration of PV-001, and the overall safety profile was consistent with expected findings, supporting the favorable clinical safety of PV-001. Robust increases in both anti-HPV L1 VLP IgG and neutralizing antibody titers were observed for all nine HPV types following the second and third vaccine doses, relative to baseline. Interpretation: PV-001 was well tolerated and elicited strong immunogenic responses, supporting its potential for further clinical development and the evaluation of broader target populations and age groups. Funding: This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: RS-2023-KH134909).