Vaccine Enhancement Stories Hit the Press

As many people feared when the Phambili trial statements were released on Tuesday, the mainstream media has picked up on the reported possibility that vaccine recipients experienced an increased risk of acquiring HIV infection.

AIDS Vaccine May Increase Infection Risk - Researchers (Reuters)
HIV vaccine trial participants warned of possible increased risk of HIV (Washington Blade)
Warning is Sent to AIDS Vaccine Volunteers (Washington Post)

Despite a large investment on the part of NIAID in HIV vaccine communications, the totality of what has occurred over this past week can best be described as a horrific mess of uncertainty and confusion. The Washington Blade article, the most comprehensive of the three, suggests that the Phambili DSMB did not just review data from the STEP trial, but also preliminary data from the ~800 people enrolled in the Phambili trial. If a similar disconnect was seen between the number of infections among people that received one vs. two immunizations, that might offer another explanation for the recommendations regarding the possibility of vaccine-induced enhancement.

The AIDS Vaccine Advocacy Coalition is releasing a statement today emphasizing that it is the safety of the STEP and Phambili trial participants that must be prioritized, and that caution should be exercised about over-interpreting statements regarding enhancement until details of the actual data are available.

Comments

[Bob Huff]

I think the key unanswered question right now is: did they South African DSMB see an interim analysis that confirmed the report from STEP? Even if there was such an early analysis (6 months??) how meaningful could it be?

We seem to have gone from futility to freak-out in a remarkably short time.

Nevertheless, I think it is crucial that volunteers in these studies are followed up thoroughly. Unlike with stopping a drug trial, the vaccine intervention can't be turned off, and endpoints will continue to accumulate.

There may also be a behavioral component to the rate of infections in these trials, and the attention the studies are getting may help reduce those risks.