Vaccination Against Human Papillomavirus (HPV) in Women and Men After Stem Cell Transplantation

What this Trial Is About

Patients who have undergone allogeneic stem cell transplantation face long-term immune deficiencies due to the transplant and possible complications like graft-versus-host disease (GvHD). This increases their risk of secondary cancers, including those linked to human papillomavirus (HPV), such as cervical cancer, which is reported to be 13 times more common in these patients compared to healthy individuals. This trial aims to study the immune response after vaccination with the 9-valent HPV vaccine (Gardasil 9®) in adults up to 45 years old who have had this transplant, comparing early vaccination starting 9 months after transplant with late vaccination starting 15 months after transplant. Participants are randomly assigned to one of two groups: the early vaccination group receiving Gardasil 9® beginning 9 months post-transplant, and the late vaccination group starting the vaccine at 15 months post-transplant. Both groups receive the vaccine as part of post-transplant care. This phase 2 trial evaluates how the timing of vaccination influences the body's antibody response to HPV. During the study, participants undergo evaluations of their antibody levels against HPV types at specific time points after transplant and vaccination, including measurements at months 16, 22, 27, and 33 post-transplant depending on their group. The main outcome is the antibody level against HPV type 16. Researchers also monitor responses to all nine HPV types covered by the vaccine, seropositivity, and seroconversion rates. The trial will continue through October 2029, with careful safety monitoring and follow-up assessments.

Vaccination Against Human Papillomavirus (HPV) After Allogeneic Stem Cell Transplantation