By David Gisselquist and Simon Collery
It has become popular to present HIV as if it is now manageable if we would just spend more money, usually more money on drugs. In addition to the new drugs that continue to be produced, the real changes involve how those drugs are used. Instead of being targeted at those most in need, the aim seems to be to sell as many of them as possible. At one time, those selling drugs (and 'solutions') seemed content just to increase the number of HIV positive people taking the drugs once they have reached what is considered to be an appropriate clinical stage. But, as we shall see below, there are now plans to keep pregnant women who are HIV positive and on mother to child transmission programs on antiretroviral treatment (ART) for life, to start treatment early for those who have not yet reached an appropriate clinical stage and even to put HIV negative people on a treatment program called pre-exposure prophylaxis (PrEP).
Donor aid for ART expanded from low levels before 2004 to save millions of Africans from dying of AIDS. As of December 2010, an estimated 5.06 million Africans were taking ART (this is the latest available estimate from WHO). Treatment is for life. As of 2012, donors pay for most ART in Africa, with the US putting up the lion’s share of aid through the President’s Emergency Program for AIDS Relief (PEPFAR).
A lot has been achieved. Even so, as of December 2010 only 49% of Africans who needed ART to stay healthy (whose CD4 cells fell below 350 per cubic centimeter [cc] of blood before starting on ART) were getting it. The untreated 51% have not been tested for HIV, have not tried to get ART, or have tried but failed.
Although donors have made a big contribution to ART for Africans, the donor-pay-for-ART model is not the long-term answer. Let’s play out some numbers to 2020.
Because an estimated 2 million Africans were newly infected with HIV each year during 2000-10, the number progressing to low CD4 cells and thereby needing ART to stay healthy will increase by an estimated by 2 million per year through 2020. Over 10 years from 2010 to 2020, that’s another 20 million needing treatment. If we suppose that 70% of these 20 million people will be alive and treated in 2020, that’s 14 million to be treated. In addition, if 4/5ths of those already receiving treatment in 2010 are alive in 2020, that’s another 4 million to be treated. The total receiving treatment (because they need it to stay healthy) would reach 18 million by 2020.
The WHO has also advised that all HIV-positive pregnant women take ART during pregnancy and for as long as they breastfeed. If HIV-positive women do so, and if they stop breastfeeding after 6 months, less than 5% of their babies would be infected vs. 35% with no treatment. With results like that, ART for pregnant and breastfeeding women is a priority. If all pregnant women take ART from their 14th week of pregnancy through 6 months of breastfeeding and then go off ART, that would add roughly 1 million women to the total needing treatment at any time over the next decade, for a total of 19 million on treatment in 2020.
Nineteen million Africans on ART in 2020 is almost 4 times the number treated in December 2010. A significant percentage of this 19 million people on ART will have passed from first to second and third line drugs, which are currently many times more expensive.
Will we get to 19 million Africans on ART in 2020? I see three options: (a) drug company revenues from ART in Africa go up at least 20% per year; (b) far less than 19 million people will be treated; or (c) prices for generics will drop, and more ART drugs will be available as generics. The first option is unrealistic. So the choice is between: option (b), which would represent a return to the late 1990s scenario with Africans dying of AIDS while Europeans and Americans live with treatment; or option (c), more and cheaper generics.
Considering mounting deaths with option (b), I suspect option (c) will be achieved. Africans will get access to more and cheaper generics than are available today, despite reprehensible efforts by US and European pharmaceutical companies and governments to prevent it.
What’s involved in option (c)? Much cheaper generic drugs for ART could become a reality if more companies in more countries produce and sell them through competitive international trade to private as well as public buyers in low and middle income countries. With competitive trade in ART drugs into Africa, a lot of drugs could go through private pharmacies for private doctors to prescribe and patients to buy, without going through government, donor programs, or NGOs.
With this option, treatment costs could be brought so low that a majority of people infected in even the poorest countries could pay out of pocket for drugs and treatment from private providers. That would leave only the poorest along with priority populations (especially pregnant women, to prevention mother to child transmission) to depend on ART and treatment provided by their own governments, NGOs, or donors.
In this scenario, donors could continue to contribute for AIDS care at the current rate, but they would be paying for ART for not more than 10%-20% of those who need it. African governments and patients would pay for most treatment. Donor aid and government budgets would go further, since they, too, could buy cheaper drugs from competing generic producers.
From the above estimates, it will take major changes in trade policies and health aid programs for ART to reach 19 million Africans in 2020 in order to keep HIV-positive people alive and healthy and to stop mother-to-child transmission. But instead of focusing on this challenge, many influential AIDS experts during 2012 diverted attention to proposals to extend ART to healthy Africans under the banner “ART as prevention.”
Advocates for ART as prevention propose several interventions:
1. The most conservative proposal for treatment as prevention is to continue women on ART after pregnancy and breastfeeding, no matter the level of their CD4 cells when they began ART. WHO designates this as the B+ strategy, where B is ART during pregnancy and breastfeeding, and B+ continues ART for healthy women after breastfeeding ends. This would add about 4 million women to ART during 2010-20. Treatment would reach 23 million people by 2020. The proposed benefit from this B+ program is protection for HIV-negative husbands. There is no evidence that women who start ART when they have more than 350 CD4 cells per cc of blood get any health benefit, and they may even be hurt.
2. A more ambitious proposal is to treat all adults who are HIV-positive no matter how many CD4 cells they have. It takes an average of about 7 years after infection for someone’s CD4 cells to fall below 350 per cc of blood. WHO estimated 22.9 million Africans living with HIV in 2010 of which 10.4 million needed treatment and 12.5 million had enough CD4 cells to stay healthy. If we assume that the annual number of new HIV infections in Africa continues steady at 2 million during 2010-20, the number of Africans infected but not yet needing treatment will tend to stay steady over 2010-20 at about 12.5 million. Suppose that ART as prevention reaches 56% (7 million) of the 12.5 million who do not need it to stay healthy (this includes women in the B+ program): treatment would reach 26 million by 2020.
3. The third proposal for ART as prevention is to put HIV-negative people considered to be at high risk to get HIV on daily treatment with a combination of two anti-retroviral drugs that goes by the brand name Truvada. In multiple trials in Africa, the Truvada has been inconsistently effective, reducing the rate people get new infections by nothing on one trial to as much as 83% in another. It comes with rare but serious side effects. Even if it were free, who should take it in Africa? Ignoring these concerns, suppose that approximately 10% of HIV-negative adults in the 9 countries with the worst HIV epidemics in southern African take ART as prevention, this would add another 10 million adults on ART. Treatment would reach 36 million by 2020.
How much would giving ART or Truvada to healthy people cut HIV transmission? Considering condom use as an alternate or additional protection, treating HIV-positive people would have only a minor effect on sexual transmission. Similarly, HIV-negative people who take Truvada to prevent HIV have the option to use condoms, with or without Truvada. If people taking ART or Truvada are less likely to use condoms, the added prevention is minor and may even be negative.
Another factor that must be considered is the impact of treatment as prevention on non-sexual HIV transmission – through skin-piercing procedures in health care and cosmetic services. Although not much is known about the risks and scale of blood-borne HIV transmission in Africa, evidence from other countries suggests efficient and rapid transmission through unsafe health. In hospitals and clinics with unsafe procedures, HIV has been observed to spread from one to more than a hundred patients in less than a year. Such rapid transmission through hospital-based outbreaks would not be found or stopped by treatment as prevention. Aside from outbreaks, people on ART with low viral loads would be less likely to transmit through bloody instruments. But a much more effective strategy to reduce blood-borne transmission is to educate and warn the general public about risks, trace unexpected infections to find and stop outbreaks, and strengthen infection control in health care and cosmetic settings. Once that’s done, how much blood-borne transmission will remain to be reduced by ART as prevention?
Overall, these various proposals for treatment as prevention would add 4-17 million people on ART (including Truvada) on top of the 19 million needing ART to live or to prevent mother to child transmission. None of these numbers are realistic without much cheaper generics for Africans. Once that’s solved, will healthy HIV-positive Africans buy and take drugs to protect others, despite the threat to their own health? Will discordant couples choose ART – with all its side effects – rather than condoms?
First things first – let’s figure out how 19 million Africans who will need ART to live and to prevent mother to child transmission by 2020 will be able to get it. Given limited donor and government funds, it’s hard to imagine that 19 million people will be treated without a large proportion of them buying low cost generic ART drugs and treatment from private providers at full cost with their own funds.
If donor and government funds fall far short of treating all those who need it – which seems likely – does it make sense for donors to subsidize treatment as prevention (ART and Truvada) for people who do not need it for their own health? If the cost of generics can be brought so low that people who need ART for their own health are able to afford it without aid, then it is reasonable to leave treatment as prevention to private trade and patient choice as well, and with their own funds. Even then, unless and until we get new information or better drugs, treatment as prevention is not something to recommend, except in rare situations for limited periods (such as a discordant couple wanting to conceive).
So there are plenty of alternatives to putting more and more people on high cost ART. For a start, the cost of drugs could be lowered substantially. Generics are cheaper than the branded versions, but they are not cheap enough yet. And many of the people who would be on ART under some of the above proposals will benefit more from measures such as reducing non-sexually transmitted HIV in healthcare facilities, increased condom use, and various other measures. Indeed, in many instances where risk of HIV infection is high and drugs are being presented as the only option, drugs are unlikely to have much impact; and in many instances where people's risk is low, again, drugs are unlikely to have much impact.
[For more about non-sexual HIV transmission and mass male circumcision, see the Don't Get Stuck With HIV site.]
Saturday, September 15, 2012
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