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HPV vaccine prevents external genital lesions in young men

Clinical Question:
How effective is the human papillomavirus vaccine for young men?

Bottom Line:
The quadrivalent human papillomavirus (HPV) vaccine reduces the incidence of external genital lesions in sexually active young men, although the absolute benefit is small (2.6% absolute risk reduction over 3 years). Its long-term safety and its impact on penile cancer, cervical cancer in partners, the use of condoms, and the transmission of other sexually transmitted diseases is unknown. (LOE = 1b)

Giuliano AR, Palefsky JM, Goldstone S, et al. Efficacy of quadrivalent HPV vaccine against HPV infection and disease in males. N Engl J Med 201;364(5):401-411.  [PMID:21288094]

Study Design:
Randomized controlled trial (double-blinded)




In this study, 4065 sexually active young men aged 16 years to 23 years (16 years to 26 years if homosexual) were randomized to receive the quadrivalent HPV vaccine (Gardasil or Silgard) aimed at HPV 6, 11, 16, and 18, or matching placebo. Most patients were heterosexual (85%), and the groups were racially diverse (35% white, 20% black, 20% Hispanic, 10% Asian, and 15% other). The authors reported both intention-to-treat results and per-protocol results, the latter defined as no evidence of HPV infection at baseline, all 3 immunizations, no protocol violations, and complete follow-up (69% of patients). Patients were followed up for a median of 2.9 years. The vaccine caused seroconversion in 97.4% of participants who received all 3 doses. External genital lesions were seen less often in the treatment group by the intention-to-treat analysis (1.8% vs 4.4%; P < .05; number needed to treat [NNT] = 38). Efficacy was similar for high-risk lesions (65% relative reduction compared with 60% relative reduction for all external genital lesions). Fewer lesions were also observed in the treatment group with the per-protocol analysis (0.3% vs 1.8%; P < .05; NNT = 67). Efficacy was lower (and did not reach statistical significance) in the subgroup of men who have sex with men. Persistent infection with HPV subtypes 6, 11, 16, and 18 was also reduced in the intention-to-treat analysis (3.6 vs 6.9 per 100 person-years; P < .05; NNT = 30). Adverse events were mild.


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