[links.health, links.sexuality]

[wispfox]

From fourgates, Merck's cervical cancer vaccine wins US approval. Unfortunately, it's currently only for women between 9-26, so I'm a little over their cutoff age.

Comments

[fourgates.livejournal.com]

I think they simply limit it to the populations where they can show efficacy, and it's a lot more work to show efficacy in the older groups. The dependent variable in these studies is not incidence of HPV but incidence of conversion from HPV- to HPV+ (well, there are several dependent variables, but they're essentially evidence for the same thing). Conversions are most frequent in the younger, more sexually active (more partners) years. So while 80% of all women may have contracted HPV by age 50, they're more likely to catch it while younger. Back to the base rates for conversions: if the conversion rate for people age 21-30 is 2% per year and the conversion rate for people age 31-40 is 1%, it'll take at least twice as many study participants to demonstrate positive effect from the vaccine with the same degree of certainty. It's not that the drug companies don't care about the older market; they just want to go at it in the most sensible order.

[joedecker.livejournal.com]

I think that's right, I believe it may also be possible that they started the different age-ranged trials at different times.