Focus on Immunizations

Abstract

Finer points Currently, three HPV vaccines are available for routine use: a bivalent vaccine (Cervarix—GlaxoSmithKline), a quadrivalent agent (Gardasil—Merck), and the newest 9-valent HPV vaccine, which was approved by FDA in December 2014. The bivalent vaccine protects against HPV types 16 and 18 and is indicated for use in females; the quadrivalent vaccine protects against HPV types 6, 11, 16, and 18 and is indicated for use in females and males. The 9-valent vaccine covers the same strains as the quadrivalent vaccine along with ve additional strains (31, 33, 45, 52, and 58) and can be used in both females and males. In its recent guidance, CDC noted that the majority of HPV-associated cancers occur as a result of HPV types 16 and 18 (which are in all three vaccines), but the 9-valent vaccine offers additional coverage for other HPV types that account for approximately 14% of cancers in females and 4% of cancers in males. CDC noted that the 9-valent vaccine can be used to continue or complete the three-dose series. For those who have already completed the three-dose HPV series with the bivalent or quadrivalent vaccine, there is no recommendation for routine administration of the 9-valent vaccine. However, CDC summarized data in patients who completed a threedose series with the quadrivalent vaccine and were then subsequently given a three-dose series of the 9-valent HPV vaccine 12 to 36 months later. The majority of patients (>98%) developed antibody titers against the ve additional HPV types.