via AIDS Treatment News, by John S. James

This is a superb description of the iPrEx trial, with a smart analysis of it’s implications. A must-read.


Why did so many of the study participants not take the Truvada?

No one knows for sure at this time. But something unusual and unexpected happened in this study. This clinical trial took place at 11 sites in 6 countries — with two of the 11 sites in the United States (Boston and San Francisco — with 113 U.S. participants on Truvada, 114 on placebo). And adherence at the U.S. sites was much better than at the non-U.S. sites — 97% among all the U.S. participants, considered extremely good, compared to far less overall. The “44% effective” headline just averages these very different situations.

We know of three theories about this difference: (1) The U.S. participants were about 10 years older on the average (though this would hardly explain the huge adherence differences observed); (2) Many of the non-U.S. participants were living at home and probably not “out” to their families, so they would have needed to conceal their participation in the study, making adherence difficult; or (3) Boston and San Francisco have excellent HIV treatment access, perhaps the best in the U.S., while in many countries most people with HIV are dying with no treatment at all. So trial participants may have given or sold their pills to someone with immediate need.

We think that the latter is most likely.

Whatever the reason, the excellent U.S. adherence shows that people can use the drug properly for prevention. And in the future, patients will know that they are getting the active drug (not a placebo), and that it has been proven to work — both of which should boost adherence. Researchers need to find out what went wrong at some of the sites, and learn how fix it.

But the bottom line is that we do have proof of principle that Truvada prophylaxis can work in high-risk gay men, and prevent close to 100% of the HIV infections that would otherwise occur.

Read the rest.

[If an item is not written by an IRMA member, it should not be construed that IRMA has taken a position on the article’s content, whether in support or in opposition.]