Adjuvant VACcination against HPV in surgical treatment of Cervical Intra-epithelial Neoplasia (VACCIN study) a study protocol for a randomised controlled trial

BACKGROUND: Cervical cancer is caused by Human Papilloma viruses (HPV) and is preceded by precursor stages: Cervical Intraepithelial Neoplasia (CIN). CIN is mostly found in women in their reproductive age and treated with a Loop Electrosurgical Excision Procedure (LEEP). The recurrence or residual disease rate after treatment is up to 17%. These women have a lifelong increased risk of recurrent CIN, cervical cancer and other HPV related malignancies. Furthermore, LEEP treatments are associated with complications such as premature birth. Limited data show that prophylactic HPV vaccination at the time of LEEP reduces recurrence rates, therefore leading to a reduction in repeated surgical interventions and side effect like preterm birth. The primary study objective is to evaluate the efficacy of the nonavalent HPV vaccination in women with a CIN II-III (high-grade squamous intraepithelial lesion (HSIL) lesion who will undergo a LEEP in preventing recurrent CIN II-III after 24 months. METHODS: This study is a randomised, double blinded, placebo controlled trial in 750 patients without prior HPV vaccination or prior treatment for CIN and with histologically proven CIN II-III (independent of their hrHPV status) for whom a LEEP is planned. Included patients will be randomised to receive either three injections with nonavalent (9 HPV types) HPV vaccine or placebo injections (NaCL 0.9%) as a comparator. Treatment and follow-up will be according the current Dutch guidelines. Primary outcome is recurrence of a CIN II or CIN III lesion at 24 months. A normal PAP smear with negative hrHPV test serves as surrogate for absence of CIN. At the start and throughout the study HPV typing, quality of life and cost effectiveness will be tested. DISCUSSION: Although prophylactic HPV vaccines are highly effective, little is known about the effectivity of HPV vaccines on women with CIN. Multiple LEEP treatments are associated with complications. We would like to evaluate the efficacy of HPV vaccination in addition to LEEP treatment to prevent residual or recurrent cervical dysplasia and decrease risks of repeated surgical treatment. TRIAL REGISTRATION: Medical Ethical Committee approval number: NL66775.078.18. Affiliation: Erasmus Medical Centre. Dutch trial register: NL 7938. Date of registration 2019-08-05.