A Phase III immunobridging trial comparing Cecolin 9 against Gardasil 9 in a single-dose regimen reported its six-month interim results at IPVS 2026 in Athens last week, giving the global HPV prevention community an interim look at data from a study that won’t reach its final readout until 2028. The gap between now and that endpoint matters because the single-dose question remains unsettled at program scale, and the answer shapes how far a fixed vaccine budget stretches across national immunization programs.
The study, PATH’s SHINE I (CVIA 104), is a double-blind, randomized, multinational Phase III trial enrolling girls aged 9 to 14 and young women aged 15 to 20 across Ghana and the Philippines. It measures immunogenicity and safety of single-dose Cecolin 9 against single-dose Gardasil 9 in those two age cohorts separately. Dr. Nana A. Ansah of Ghana’s Navrongo Health Research Centre presented the Month 6 interim analysis during the scientific program. The trial design places the two vaccines in direct comparison rather than against placebo, so the interim data will inform whether the immune response Cecolin 9 generates at six months tracks closely enough with Gardasil 9’s to support equivalence arguments when final results arrive.
Xiamen Innovax Biotech, which manufactures Cecolin 9, also holds the WHO prequalification it earned in October 2021 for Cecolin, its bivalent HPV vaccine. Cecolin 9, the 9-valent successor built on the same E. coli-derived virus-like particle platform, launched in China in 2025. The E. coli expression system is a manufacturing distinction from yeast-based competitors like Gardasil 9, which Merck has produced since its 2014 FDA approval, and the approach is central to Innovax’s case for scalable, lower-cost supply. Whether that manufacturing advantage translates into procurement wins in GAVI-eligible markets depends partly on what SHINE I’s 2028 final data show about durability and breadth of protection from a single dose.
The concrete marker to track is the 2028 final readout from SHINE I. If the data confirm non-inferior immunogenicity against Gardasil 9 in both age groups, Cecolin 9 carries a credible path toward procurement recommendations for single-dose programs in low- and middle-income countries, where dose-count reduction has direct cost and logistics consequences for national programs.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
