At least 5 years of protection from Merck HPV vaccine

A few weeks ago, we discussed the news from GSK that their cervical cancer vaccine, Cervarix, appears to provide at least 4.5 years of protection against the pre-cancerous lesions caused by HPV types included in the vaccine. Today, news from a conference in Paris that Merck's vaccine, Gardasil, offers at least 5 years of such protection. Reuters has the story.

We should expect these back-and-forth announcements every few months from each manufacturer as long-term follow-up data continues to trickle in. The question needing an answer is how long immune protection lasts following the initial HPV vaccination series. These results will help determine whether booster doses are needed, and if so, how often.

Among the advantages of these follow-up studies led by the vaccines' manufacturers is the head start it provides in advance of the vaccines' public debut. If immunity does wane at some point, we know (a) that it appears that it won't for at least 5 years and (b) there will be ample time to implement recommendations for booster doses well before the initial public vaccine recipients near the point at which immune protection would otherwise begin to fall.