When a PrEP trial produces poor results, the reaction is often to point the finger at the patient: they didn't take the drugs regularly, 'adherence' was low, etc. The irony of this is that people thought of as good candidates for PrEP are often those who have not successfully modified their Sexual Behavior, or have shown themselves unwilling to do so. If they will not or can not modify their sexual behavior, why would they be more willing or able to modify their drug taking behavior?
Some drug trial reports parcel up the high achievers and exclude the low and medium achievers and call it a 'sub-study' or something similar. But the point of a randomized controlled trial is to make it clear what kind of result can be expected of people taking part, not what kind of result can be expected if everyone behaved as drug manufacturers would wish them to. Given that people don't behave in real life as they do during drug trials, the results for strategies such as PrEP so far have been somewhat encouraging, but not good enough to roll out the strategy.
Even with PrEP, people are encouraged to engage in safe sex, to limit their number of partners, to use condoms, etc. If they can't or won't do some or all of those things, PrEP will not be very effective; but it may not have any positive impact at all. Those behind the trials and those producing the drugs are anxious to portray the strategy as tested and proven, but it is most definitely not, not yet anyhow. One of the main exponents of the strategy tries to persuade us that PrEP is the way to go, but some of his readers are clearly not convinced. And the opposing case raises additional concerns about PrEP, referring to the strategy as 'grasping at straws'.
In countries where HIV prevalence is very high and transmission is highest among low (sexual) risk groups, those engaging in heterosexual sex with one HIV negative partner, PrEP is not going to be feasible. Those who face the lowest risk, but are paradoxically the highest risk group in Modes of Transmission Surveys, are unlikely to be targeted by a PrEP campaign.
And given that the majority of HIV positive people in need of treatment are still not receiving it due to cost, infrastructure, political and other reasons, it would be odd to offer the same drugs to people who are still HIV negative. It would seem far better to establish what exactly the risks are and address those risks before throwing yet more drugs at the problem. But PrEP is the way to go if you want to sell lots of drugs to healthy people; if that doesn't work, you'll then have lots of sick people to sell even more drugs to.Pre-exposure prophylaxis (PrEP) involves putting HIV negative people on antiretroviral drugs (ARV) with the aim of protecting them from HIV infection. read more..
Thursday, 9 August 2012
Randomized Controlled Trial-Drug Manufacturers-Sexual Behavior-Drug Trials
Saturday, 19 May 2012
Pre-Exposure Prophylaxis-African Countries-Hiv Negative-HIV
Apologies for the lack of posting this year but I have had enough work keeping my other blog going. The subject of PrEP and related issues do also crop up there, though.
Daily use of Truvada has been backed for pre-exposure prophylaxis use by a panel of 'experts', which generally refers to people who are so well paid to say the right thing that no one else will disagree with them. It's likely that this use of the drug will soon be approved by the FDA. I wasn't able to find a register of the 'experts'' interests but I'm sure it would make interesting reading.
If approved, the drug will be prescribed for HIV negative people who are thought to be at high risk of being infected sexually, which generally refers to men who have sex with men in Western countries. The drug is not being considered for use by intravenous drug users. It is also unlikely to be of much value for commercial sex workers in wealthy countries as they are rarely infected unless they are also intravenous drug users or face other serious risks.
This suggests that PrEP is unlikely to be effective in high HIV prevalence developing countries, where high risk groups are not easy to identify. In many African countries, the bulk of infections among adults occur in married people and those in long term relationships, who don't face very high sexual risks. In other words, the drug is of little use as PrEP where it is most needed. But I'm sure that won't stop Big Pharma from lobbying the right people so that the potential tens or hundreds of millions of Africans can be exploited.
The process of palming off useless but extremely expensive drugs with potentially dangerous side-effects on Africans has been eased by years of publicity for the dominant HIV transmission paradigm, which says that almost all HIV in African countries is transmitted through heterosexual behavior. The fact that the paradigm is seriously challenged by empirical data has done little to influence policy, which concentrates on the politician, religious leader and media friendly process of wagging fingers, pointing fingers and poking fingers into the many HIV fuding pies.
Opposition from groups who claim to represent the interests of HIV positive people has almost all been taken care of in the time honored fashion of paying off anyone who speaks out of turn (or rubbishing anyone who won't take payment). A rare voice of dissent comes from the Aids Healthcare Foundation, which has consistently opposed the current trend of rushing into practices which have little empirical backing, but which mysteriously receive full backing from 'experts'.
Pharmaceutical front group Aids Vaccine Advocacy Coalition (AVAC), predictably, blow the trumpet for PrEP; pharmaceutical products ostensibly produced to treat illness would never have become as profitable if they were only used by sick people. But the UK's Nick Partridge puts his finger on the problem, probably inadvertently: "But we need to know if people at highest risk of infection are prepared to take a pill every day and whether there would be an increase in risk-taking behaviour which could outweigh the prevention effectiveness of Truvada."
The truth is, we don't know who is at highest risk in high prevalence countries, we know that most will not take the pill every day and it's very likely there will be an increase in risk-taking behavior, especially where people opt for PrEP because they know (or even think) they are at risk.
[For more about non-sexual HIV transmission and male circumcision, see the Don't Get Stuck With HIV site.]Pre-exposure prophylaxis (PrEP) involves putting HIV negative people on antiretroviral drugs (ARV) with the aim of protecting them from HIV infection. read more..
Monday, 23 April 2012
Sexually Transmitted Infections-Hormonal Contraceptives-Hormonal Contraception-Population Control
The English Guardian may face something of a dilemma when covering the WHO's failure to give clear advice to African women who have been persuaded to use Depo Provera and similar injectable Hormonal Contraceptives, which appear to be associated with a doubling of HIV transmission from females to males and from males to females; Birth Control is close to the heart of he who would control Population, Bill Gates, whose Foundation sponsors the paper's Global Development section. Not that the article appears in the Gates sponsored section; perhaps there is no such dilemma.
But Sarah Boseley sticks pretty close to the WHO's press release and says that women who use injectables such as Depo Provera should also use Condoms. As with the 'advice' from WHO, Boseley notes the use of 'dual protection' against pregnancy, on the one hand, and infection with sexually transmitted infections on the other. For Boseley and WHO, this means using condoms along with Depo Provera. But what neither seem willing to point out is that condoms on their own provide such dual protection.
So why would anyone want to use these expensive and possibly dangerous hormonal injections if condoms on their own give dual protection? Well, according to WHO and other 'experts' in reproductive health (often just a useful term for 'birth control'), condoms are not 'female controlled'; many people don't use condoms if they can help it. So rather than recommending that people who wish to avoid both pregnancy and sexually transmitted infections should use condoms, they recommend that people use Depo Provera, despite knowing that many people who opt for injectable hormonal contraceptives (and various other methods) cease to use condoms?
The oral versions of Depo Provera and similar contraceptives are said to be unsuitable because women need to take them daily and they may forget, or their husbands may object, etc. Injectable versions are said to be women controlled and only need to be taken every three months. In reality, they are to a large extent controlled by those who supply them, often NGOs and other institutions who believe strongly in the population control paradigm of development. Whatever synonyms are used, the concept of control is always detectable.
Boseley claims that women 'choose' Depo Provera and similar products but these pharmaceuticals are aggressively marketed by some of the biggest NGOs working in population control. Use of injectables has increased considerably over recent years but it's difficult to work out whether that's a matter of availability or genuine choice. Given the political and financial clout that NGOs and institutions such as the Gates Foundation have over the lives of people in developing countries, it seems unlikely that birth control is as high on the agenda of people in African countries as it is for the various non-African parties on the bandwaggon. One might even wonder if anyone gives a damn what Africans think about such matters.
It's astonishing just how uncritical Boseley is, in fact. She parrots bits about the WHO's 'expert group', but it was not concluded that hormonal contraception is safe ("Current evidence is not strong enough to prove or disprove an increased risk of HIV from hormonal contraception"). Rather, it has clearly been decided that it is safe enough for Africans and other poor people; it is not much used by white, middle-class Westerners. These products have not been shown to be safe, far from it. But the most important consideration for the WHO is that their goal of population control is not compromised by worries about safety issues, which they have been aware of for decades.
The logical conclusion to be drawn from the WHO's findings is that, if people want to avoid unplanned pregnancy and sexually transmitted infections, they should use condoms. The WHO statement is not based on a logical conclusion; it is a political declaration designed to protect the interests of Big Pharma read more..
Sunday, 4 March 2012
Food And Drug Administration-Pre-Exposure Prophylaxis-Transmission Of Hiv-Favorable Findings
A few days ago, an article appeared on AidsMeds.com about the drug Tenofovir being associated with an increased risk of irreversible kidney disease, which does not reverse even when the drug is no longer taken. Tenofovir is one of the main ingredients in a vaginal gel developed to reduce the Transmission Of Hiv, although a recent trial was stopped early because the gel was found to be ineffective. Another trial of Tenofovir taken orally as pre-exposure prophylaxis was also stopped early as it was clear it would not be possible to demonstrate a difference in effect between the drug and a placebo.Despite these findings, Poz.com reports that the US Food And Drug Administration (FDA) has accepted an application from the makers of Tenofovir, Gilead Sciences, to give a priority review of the use of the drug, in combination with emtricitabine, to be marketed as Truvada. Despite some less favorable findings about Tenofovir, the more favorable findings led to immediate calls for application for use as PrEP to be fast-tracked.In addition to the above worries about Tenofovir, widespread use of PrEP is also likely to give rise to drops in use of condoms. This possibility is denied vigorously by defenders of PrEP, and some data has been produced to support that defence. But like male circumcision and the hormonal contraceptive Depo Provera, people tend not to think about dual protection against both HIV and unplanned pregnancy.Interestingly, while injectable versions of Depo Provera and similar methods are said to be 'female controlled' relative to the oral version, this objection doesn't appear to be used or alluded to by proponents of PrEP or vaginal gel.A paper has been published discussing these diverging trial results and the authors pay particular attention to adherence to the drug regime, which needs to be very high. The authors mention identifying "optimal populations for PrEP"; but they may find that these populations are least likely to need the drug. It's all beginning to sound like a product in search of a market; but where would Big Pharma be if it never took that approach?Pre-exposure prophylaxis (PrEP) involves putting HIV negative people on antiretroviral drugs (ARV) with the aim of protecting them from HIV infection. read more..