When the project began in 2020, there were only three World Health Organization (WHO) prequalified HPV vaccines available, all of which are manufactured by large, multinational vaccine developers and can be expensive for LMICs to procure—especially for the middle-income countries that aren’t eligible for support from Gavi, the Vaccine Alliance.
The world needed additional, affordable HPV vaccines if it were to make progress toward reaching global HPV immunization goals—in particular, the WHO’s Global Strategy to Accelerate the Elimination of Cervical Cancer, which calls on countries to, by the year 2030, fully vaccinate 90 percent of girls with HPV vaccine by age 15.
We found a way forward in a vaccine in China. In 2019, Xiamen Innovax Biotech Co. Ltd. licensed Cecolin®, an affordable bivalent HPV vaccine that protects against the two most common types of HPV that cause cervical cancer, for use in China—and they were interested in bringing it to the global market. PATH’s chemistry, manufacturing, and controls experts were already supporting Innovax in preparing Cecolin for WHO prequalification but the world needed supplemental information that would demonstrate Cecolin’s effectiveness in populations outside of China and build a broader evidence base for use in LMICs.
With funding from the Gates Foundation and the Federal Ministry of Research, Technology, and Space in Germany via KfW Development Bank, PATH designed and sponsored a Phase 3 clinical trial of Cecolin in Bangladesh and Ghana to evaluate extended and alternative dosing schedules, which could allow countries flexibility in how to vaccinate their populations. We chose Bangladesh and Ghana because, at the time the trial began, neither country had HPV immunization programs in place but both were actively considering them due to suffering high burdens of HPV infection and cervical cancer death, and the generation of clinical data in their countries would likely support decision-making.
The trial ran between 2021 and 2023 and examined how Cecolin performed compared to Gardasil® (which has been available since 2006 and is the most commonly used HPV vaccine in LMICs) in 9-to-14-year-old girls in various dosing schedules. We worked closely with the local investigators that conducted the trial, providing administrative oversight, scientific guidance, and operational support throughout.
And it was a huge success. Results showed that Cecolin was well tolerated, highly immunogenic in extended and alternative dosing schedules, and generated immune responses comparable to Gardasil. But more than that, it demonstrated that a single dose of Cecolin was able elicit an immune response comparable to a single dose of Gardasil, which had already demonstrated single-dose effectiveness in previous studies.
This was significant because in 2022, WHO updated its HPV vaccine recommendations and endorsed a single-dose schedule, which expands access to HPV vaccination by reaching more girls and reducing financial and logistical barriers. Cecolin was already poised to be a valuable asset in the global HPV prevention toolkit, but if it could be administered as a single dose, its impact would be far more significant.
We presented this data to WHO. Based on the results of the PATH-sponsored study, in October 2024, WHO revised its Considerations for HPV Vaccine Product Choice document and added Cecolin to the list of HPV vaccines that can be administered on a single-dose schedule.
“This was a significant success, and a celebratory moment for global HPV prevention,” said Niranjan Bhat, PATH Senior Medical Officer and HPV SIHE project leader. “Cecolin, prequalified in 2021 with PATH support, now comes with a single-dose endorsement and strong evidence for its use in LMICs. Together, PATH and our partners paved the way toward better HPV vaccine access in LMICs by increasing the availability of affordable vaccine options, chipping away at supply constraints, informing policy around HPV vaccination, and overcoming logistical challenges—everything we set out to do and more.”