Efficacy of Human Papillomavirus Vaccines for Recalcitrant Anogenital and Oral Warts

Abstract

Human papillomavirus (HPV) vaccines are preventive measures to decrease HPV infection rates. Knowledge of their efficacy as treatment options for anogenital warts (AGWs) and oral warts (OWs) is limited. To evaluate the efficacy of HPV vaccinations in recalcitrant AGWs and OWs (lesions persisting more than 6 months despite conventional treatments), we compared a group of patients treated with standard therapies plus an HPV vaccine with a group of patients treated with standard therapies only. The response to treatment (in terms of the number of lesions) in the two groups was compared. Data were analyzed with the χ2 test and p values < 0.05 were considered to be statistically significant. The study included 14 patients (group A = cases) who received 3 doses of an intramuscular HPV vaccine (Gardasil 4 or Gardasil 9) in addition to the standard treatments for AGWs and OWs, and 15 age- and sex-matched patients (group B = controls) with an analogous number of lesions to group A who received only standard therapies. After 12 months, 85% of patients of group A versus 33% of group B had positive clinical outcomes (0.004). Our findings suggest a possible therapeutic role of HPV vaccines in addition to standard treatments for AGWs/OWs. Preventive vaccines, blocking the viral entry through the induction of L1-specific antibodies, can prevent autologous reinfections (through auto-inoculation) and favor the elimination of the virus.