A Clinical Study of V540A in Healthy Female Participants (V540A-005)

Researchers are looking for new ways to prevent cancers related to human papillomavirus (HPV). HPV is a common virus that can cause an infection. There are many different types of HPV. A standard vaccine to prevent HPV-related cancers is V503. V503 protects against 9 types of HPV. V540A is a study vaccine designed to protect against the same (shared) 9 HPV types plus other (unique) HPV types. Researchers want to learn if V540A: * Is safe and if people tolerate it * Works as well as V503 to cause an immune response (the body's response to protect against infections and illnesses) to the shared HPV types.

NCT Number	NCT07224477
Lead Sponsor	Merck Sharp & Dohme LLC
Conditions	Healthy
Enrollment	525 participants
Start Date	2026-07-20
Primary Completion	2028-04-04 (estimated)
Study Completion	2028-04-04 (estimated)
Updated on ClinicalTrials.gov	2026-02-19