Pre-Exposure Prophylaxis or PrEP

Pre-exposure prophylaxis (PrEP) involves putting HIV negative people on antiretroviral drugs (ARV) with the aim of protecting them from HIV infection. This blog looks at some of the pros and cons of PrEP.

Saturday, June 23, 2012

Truvada Manufacturer Gilead Stops Funding to Critics

The Aids Healthcare Foundation (AHF) provides healthcare for HIV positive people and advocacy in the broader field of HIV health. In that capacity, the AHF has criticized the pharmaceutical company Gilead Sciences on a number of issues, including drug pricing policies.

But in addition, AHF has questioned the use of Gilead's Truvada as a pre-exposure prophylaxis (PrEP), a pill to be taken by HIV negative people to give them some protection from HIV infection. It could be taken, for example, by someone whose sexual partner is HIV positive. However, PrEP is not as effective as using a condom and it doesn't protect against other sexually transmitted infections.

More importantly, using a drug like Truvada can give rise to the development of drug resistant strains of HIV, especially in users who are unknowingly infected when they start taking the drug or who unknowingly become infected while taking it. AHF have argued that every time someone gets a prescription for Truvada, they should also be able to show that they have been tested for HIV and the result is negative.

Drug manufacturers are not known for their tolerance of public accountability; as a result of AHFs actions, Gilead have stopped their funding to AHF. This is particularly unfortunate right now because approval for Truvada as PrEP, which was expected to be rushed through the usual regulatory procedures, has now been delayed so that the requirement for a negative HIV test be stipulated. But it's likely that Gilead will continue to lobby for the right to aggressively pursue their own ends at the expense of public health.

The increasing dependence on drugs with outrageously high prices is worrying even in a wealthy country like the US. But as the country has the highest HIV prevalence in the Western world, it would be an even bigger threat to the country's public health systems if widespread resistance to Truvada were to develop. As well as resistance developing in an individual taking the drug, resistant strains of HIV can also be transmitted to others.

Also of concern is that, up until now, HIV drugs have been used by HIV positive people. The use of the same drugs by people who are HIV negative should be raising questions in people's minds about how far public health should go with what is effectively medical treatment for perfectly healthy people.

They may even ask how far it is possible for public health to go; the number of healthy people should, hopefully, far outnumber the number of sick people; it's undoubtedly a great market. But some level of drug resistance is inevitable. So are companies like Gilead stealthily creating new markets for even more costly second line drugs by vastly increasing the number of healthy people taking Truvada?