Effectiveness of various human papillomavirus vaccination strategies: A community randomized trial in Finland

The quality of life of frequently vs. infrequently screened HPV vaccinated women

PURPOSE

Cervical lesions caused by human papillomavirus (HPV) are related to decreased quality of life (QoL) of women. Also, cervical cancer (CC) screening can cause psychological adverse effects. It has been assumed that by decreasing the HPV-related disease burden, HPV vaccinations would increase the QoL. This study compares the effect of CC screening on QoL of HPV vaccinated women in two different screening protocols.

METHODS

A total of 753 HPV16/18 vaccinated women were randomized to frequent (22/25/28 years of age) and infrequent (28 years of age) CC screening arms. QoL questionnaires (EQ VAS, RAND 36, amended CECA 10) were sent at the age of 28.

RESULTS

Median EQ VAS scores were 80 (Q1-Q3 75-90) in both screening arms. Mean RAND 36 scores of frequently and infrequently screened women were 78.13/81.64 in Physical role functioning domain and, respectively, 77.93/80.18 in Pain, 69.10/69.12 in General Health, 54.67/53.61 in Energy, 83.72/85.11 in Social functioning, 69.53/69.68 in Emotional role functioning, and 68.16/69.29 in Emotional well-being domain. Among women with a self-reported history of Pap cytology abnormalities, overall mean scores of amended CECA 10 were 69.52/72.07, and among women with a self-reported history of genital warts, 60.09/66.73, respectively.

CONCLUSION

There was no significant difference in the QoL of HPV vaccinated women between the two CC screening arms. Women were mostly satisfied with the screening experience despite the screening frequency. This information is important for the future screening program planning as we need to reach the best possible balance with screening benefits and harms.

TRIAL REGISTRATION NUMBER

NCT02149030, date of registration 29/5/2014.

Effectiveness of various human papillomavirus vaccination strategies: A community randomized trial in Finland

INTRODUCTION

We conducted a community-randomized trial (NCTBLINDED) in Finland to assess gender-neutral and girls-only vaccination strategies with the AS04-adjuvanted human papillomavirus (HPV)-16/18 (AS04-HPV-16/18)vaccine.

METHODS

Girls and boys (12-15 years) were invited. We randomized 33 communities (1:1:1 ratio): Arm A: 90% of randomly selected girls and boys received AS04-HPV-16/18 vaccine and 10% received hepatitis B vaccine (HBV); Arm B: 90% of randomly selected girls received AS04-HPV-16/18 vaccine, 10% of girls received HBV, and all boys received HBV; Arm C: all participants received HBV. Effectiveness measurements against prevalence of HPV-16/18 cervical infection were estimated in girls at 18.5 years. The main measures were: (1) overall effectiveness comparing Arms A or B, regardless of vaccination status, vs Arm C; (2) total effectiveness comparing AS04-HPV-16/18 vaccinated girls in pooled Arms A/B vs Arm C; (3) indirect effectiveness (herd effect) comparing girls receiving HBV or unvaccinated in Arm A vs Arm C. Co-primary objectives were overall effectiveness following gender-neutral or girls-only vaccination.

RESULTS

Of 80,272 adolescents invited, 34,412 were enrolled. Overall effectiveness was 23.8% (95% confidence interval: -19.0, 51.1; P = 0.232) with gender-neutral vaccination. Following girls-only vaccination, overall effectiveness was 49.6% (20.1, 68.2; P = 0.004). Total effectiveness was over 90% regardless of vaccination strategy. No herd effect was found. Immunogenicity of the AS04-HPV-16/18 vaccine was high in both sexes.

CONCLUSIONS

This study illustrates the difficulty in conducting community randomized trials. It is not plausible that vaccinating boys would reduce overall effectiveness, and the apparent lack of herd effect was unexpected given findings from other studies. This analysis was likely confounded by several factors but confirms the vaccine's high total effectiveness as in clinical trials.