How ethical are HIV prevention trials? Every time we announce results of a trial that compares new HIV infections in a group with or without some new intervention (a microbicide for example, or a vaccine), some journalist or other jumps on the fact that researchers are just watching people get infected. Researchers then explain that everyone in the trial gets given the best possible existing prevention services — counselling, free condoms, treatment for other sexually transmitted infections. But is that really true?
The question was raised for me while I am here in Thailand by a comment on an earlier post. It pointed out that US taxpayers, through CDC, are funding a trial among drug injectors in Thailand that withholds the very thing we know will prevent most infections: sterile needles.
CDC, on its website, points out that withholding clean needles is “consistent with Thai government policy”. And yet the agency itself recognises that needle distribution programmes reduce HIV infections. The Helsinki declaration on medical research ethics says that if you’re trying out a new drug or procedure, you’ve got to try it against the best available alternative.
In the past, I’ve argued that it is reasonable for us to read that as “the best alternative feasibly available in the country where the study is being done”. There’s no point trying a drug designed for use in a developing country against a developed-country regimen which is likely to be better, but which couldn’t ever be offered in the study country because it requires too much money, technology or expertise to administer.
The “we’re using the Thai standard of care” argument is very convenient for CDC researchers. After all, they need quite a few people to get infected, so that they can see if significantly fewer people get infected if they’re using the trial drug, tenofivir.* CDC’s other tenofivir trial, among women in Botswana, has just been downgraded, because the research team has realised that it is not getting enough infections in either group for it to be able to measure a difference. That’s in part because of very high drop-out rates — already a red flag for a prevention method that obliges you to take a pill a day for as long as you’re at risk.
We know that an adequate supply of sterile needles, and the freedom to use them without fear of arrest, can cut HIV infections dramatically among injectors. If the CDC study in Thailand gave enough needles to injectors, they probably wouldn’t have enough infections to give them a trial result. And the tenofovir-based prevention method that’s being tried is a method that could be used by other groups too — gay men and sex workers and other heteros at high risk of exposure, for whom we don’t have such easy prevention options. So you can understand why researchers are reluctant to push the envelope on providing decent prevention to study participants. But in this case, the “local standard of care” argument really doesn’t wash. It would be perfectly feasible for Thailand to provide injectors with clean needles. The country has the technology, the money and the health systems to do that. The only block is a political one. It’s bad enough that Thai authorities live with this blind spot in their otherswise quite pragmatic HIV prevention programme. The US has been just as bad at home, although there’s now light at the end of the tunnel for safe injecting programmes in the US. All the more reason that US researchers (and taxpayers) should refuse to compound Thailand’s unethical policy with unethical research.
*Info on the trials: The Thai and Botswana trials aim to investigate whether uninfected people can take a daily dose of antiretroviral drugs to stop themselves getting infected with HIV if they are exposed to the virus through sex or needle-sharing with infected people. It’s know as Pre Exposure Prophylaxis or PrEP, and you can find our a lot more about it here.