Vaccination in latent papillomavirus infections: An experimental randomized, prospective, open-label, controlled trial

Background. Human papillomavirus refers to one of the most common sexually transmitted infections with the majority of viruses in the host being transient carriers, the so-called latent forms of papillomavirus infection. Persistence of cancer-associated human papillomavirus is fraught with cervical intraepithelial neoplasia, and subsequent cervical cancer. Measures for secondary prevention of cervical cancer in latent forms of papillomavirus infection are yet to be developed, which predetermined the present study. Objectives. To increase the effectiveness of secondary prevention of cervical cancer by improving the algorithm for managing latent forms of papillomavirus infection in women . Methods. A randomized controlled trial enrolled 152 patients diagnosed with a latent papillomavirus infection. Patient examination and data analysis were carried out at clinical trial centers of the Department of Obstetrics, Gynecology and Perinatology of Kuban State Medical University (Russia) in 2020–2024. The trial involved patients aged 18 to 35 years. Patients were divided into 2 groups using the sealed code envelope method: Group I (comparison group) ( n = 74) — microbiological sanitation of the cervicovaginal zone (as indicated) and observation for 36 months with annual control of viral load, colposcopy and oncocytology; Group II (study group) ( n = 78) — microbiological sanitation of the cervicovaginal zone (as indicated) and administration of quadrivalent recombinant human papillomavirus vaccine (types 6, 11, 16, 18) (3 doses intramuscularly: second and third doses were administered 1 and 3 months after the first one). Each patient was analyzed for the effectiveness of preventive therapy according to the dynamics of indicators: colposcopy, cytology (Papanicolau staining), and molecular biological analysis (polymerase chain reaction). The indicators were evaluated after 12, 24, and 36 months. Statistical analysis of the results was carried out using IBM SPSS Statistics 26 (IBM, USA) variation statistics programs. Results. Vaccination with a quadrivalent recombinant vaccine against human papillomavirus of types 6, 11, 16, 18 against the background of correction of dysbiotic vaginal and cervical disorders in latent forms of papillomavirus infection in women was revealed to cause a 9.3-fold decrease (compared to the study group) in realization of latent persistence of viruses into subclinical (25.7 % in group I vs. 9.0 % in group II) and clinical forms of papillomavirus infection (cervical intraepithelial neoplasia) — 12.1 % in group I vs. 1.3 % in group II, to reduce the persistence of human papillomavirus and the appearance of their new genotypes, the viral load of highly oncogenic types of human papillomavirus (1.9 times —3.2 ± 2.4 geq/ml in group I versus 1.7 ± 2.1 geq/ml in group II). Conclusion. The trial has shown that human papillomavirus vaccination is associated with a reduced risk of realization of latent forms of papillomavirus infection into clinical forms as cervical intraepithelial neoplasia and, consequently, cervical cancer, thereby being considered promising for secondary prevention of this pathology.