Sunday, September 27, 2009

No HIV vaccine just around the corner

So, I'm lounging about on a lazy Sunday morning - as we experts in HIV prevention science so often do - plotting a quick motorcycle route through Western Maryland to help callous my backside for the start of Enduro Africa later this week. 


But then I stumbled across today's NY Times article that bungles the recent HIV vaccine trial news and, importantly, includes a misplaced quote to UK-based Riders for Health, one of the charities that inspired me to do Enduro Africa. I couldn't just sit there and do nothing.

What the Times published was a recycled piece still dripping in cynicism:

Bloggers with a taste for biostatistics — and one rival AIDS vaccine specialist who declined to be quoted — said it would take only a handful more infected Thais in the vaccine column to shift the results from “statistically significant” to meaningless. Even one more would have weakened the data enough to make headlines saying “One Quarter Protected” more likely, given the way journalists round off numbers.


Actually, the margin is even closer than that. Add a single additional infection to the group assigned to the treatment arm and the 95% confidence interval would include 1.0. In other words, the observed difference could have been statistically insignificant due to a data entry error or because someone was unable to use a condom or clean needle during a single exposure event. One person.

But this fact obscures a more important one that the author fails to appreciate: After years and years of null or adverse results from HIV vaccine trials, the unexpected findings this week open a world of possibilities that will move the ball further along. Even with that hypothetical case, the findings would still be in the same direction, pointing us to new research that could yield better understanding of the mechanisms underlying an effective immune response to HIV or shed light on why a vaccine might work for some (and not others).


Curiously, the author quotes a Riders for Health representative in making the case that access to an effective vaccine would pose a whole new set of challenges, even if the findings were a "slam dunk," as we like to say here in DC:

"Millions of children across Africa still die of measles simply because the vaccine doesn’t reach them,” said Barry Coleman, founder of Riders for Health, a British charity that buys and fixes motorcycles for African health workers. "People with AIDS don’t need," he added, “another breakthrough that does not reach those who need it most."
Very true. And one could quickly make a long list of inexpensive, efficacious health promoting technologies that go underutilized for lack of access. There certainly is a need to put greater emphasis on better disseminating existing tools that work, but should we cease looking for new prevention tools at the same time?

Without a doubt, caution is in order with respect to these vaccine trial results. And, let me be the one to say it for the record, if no one has thus far: There's no HIV vaccine just around the corner. No responsible agency would recommend licensure or scale up for a vaccine with only 31% efficacy.

Still, what we have now is movement in the right direction that may lead to broader discoveries in immunology and public health. No one has declared this product to be a "miracle." What we need most is a bit of perspective here, the cynics among us included.



See the NY Times' If AIDS went the way of smallpox 


2 comments:

Howell Tumlin said...

Hello Andrew,

I hope you have a terrific experience on the Wild Coast in South Africa. I was one of two US riders on the first Enduro Africa in 2006, and it was an experience I shall never forget. I still have many friends from that trip that I keep in touch with around the world.

I have been passionate about improving healthcare in Africa for more than twenty years. I went on the first Enduro because it raised money for this purpose. It was on that trip that I first met Barry and Andrea Coleman of Riders for Health.

Which brings me to Barry's quote in today's New York Times. If I may be so presumptive as attempt to speak for Barry, I believe that true intent of his comment was simply that while medical breakthroughs like a potential HIV vaccine are critically needed, and therefore capture headlines and massive amounts of research funding, the cruel reality is that millions of people die annually because vaccines already in existence do not get to the people in greatest need of them. The lack of effective delivery systems attract neither headlines nor funding, and it is doubly cruel to the people of rural Africa to not consider how a drug will be delivered with same urgency as how quickly it can be created. Riders for Health has developed a low tech, highly effective vehicle maintenance program that provides reliable transportation for healthcare workers to take vaccines to remote villages. Developing a new HIV vaccine would be one of the great events in human history; but ensuring that it gets to the people who need it would be even greater.

Since returning from my Enduro Africa trip, I have become a volunteer for Riders for Health. We have started Riders Chapters in Los Angeles and San Francisco in the last year. Perhaps its time to have a DC Chapter? You can find out more about Riders at www.riders.org.

Best wishes,

Howell Tumlin

Andrew said...

Thanks for taking the time to comment, Howell. Based on the level of interest I've received from motorcyclists in the area (not to mention around the country), I'm certain that a Washington-based Riders for Health group could work. We should talk when I return. I'd be very interested to hear what you do as a volunteer.

Thanks also for clarifying Barry's remark. In fairness, it is the NY Times author's cynicism that I'm gunning for, not Barry's quote. I've edited my post a little to be clearer on this point.

I fully agree: there are a slew of prevention interventions in existence (e.g., vaccinations, condoms, effective contraception) or in the pipeline (e.g., daily and intermittent pre-exposure prophylaxis with anti-retrovirals) that highlight acutely the need to balance new developments with improved access to, and dissemination of, existing interventions. I often wonder how much better a bang for the public health buck could be possible just by better dissemination of existing strategies. And the scientific literature underscores your point that with innovative outreach, like those used by Riders for Health, improved health outcomes are within reach.

I'll follow up with you when I return from the trip. I'd be very interested in hearing more about how I might start a chapter of Riders for Health here in DC (www.riders.org).

Warm regards,
Andrew