HIV can't be killed. But today there are treatments that are very effective, and actually allow HIV positive persons to live as long and healthy life as those not living with HIV. So how did we get to this position? Of course when the epidemic was first detected, there was no treatment at all. By the late 1980s, one drug was being used, called AZT or zidovudine. The idea behind that an old drugs than a now is to stop the virus replicating and spreading in the body. So that the immune system recovers and actually positive patient does not become immune suppressed. But studies soon found out that that drug was not very effective and patients are suffering serious side effects. There was a proliferation of drugs being tried and given to patients. In fact, the whole regulatory process for these drugs changed in the US to allow for the rapid transition going from evidence in new drugs being helpful, to them being given to patients. But still no drug by itself has proven very effective. It seemed that the virus was able to evolve to evade the action of each drug. Then trials began combining drugs, giving two and then three drugs to the same patient. Each drug carefully selected so that it blocked a different function to the virus. So the effect evades one drug, there was something else to stop it. That did work. These first trials were in the mid 1990s, and it became called combination antiretroviral therapy or just a ART. Very rapidly, patients came to benefit from this new combination therapy in London, the US, and elsewhere. You're here at Clinical Colleagues discussing this in more detail at our round table discussion. At first, there was a substantial pill burden, lots of different pills to take and there were side effects. But over time, these will be reduced and largely overcome. Today the first-line correlation therapy is a single pill a day, which is well-tolerated. There are lots of other combinations available if you, your government or your insurer can afford it. But in the mid 1990s, all AIDS tests were starting to fall in high-income countries, deaths were still increasing in the hardest hit low-income countries. In the face of this, there was a tremendous advocacy led by the communities of HIV positive persons themselves largely, for a scale-up of treatment. The treatment at the time was expensive and difficult to administer in fragile and heavily burden health systems. But the argument was one, and after around the year 2000, there began a rapid scale-up of treatment in low-income countries. This was largely funded initially through direct financial assistance. The Global Fund to Fight AIDS, TB, and malaria, were set up as a way to raise money in order to support the scalar for treatment. PEPFAR, which is the President's Emergency Plan for AIDS relief became the biggest bilateral aid program and set ambitious targets for itself to provide treatment to millions of people. Almost two decades later, we can see the enormous progress that was made. Now, in Eastern and Southern Africa, about two-thirds of people living with HIV are on treatment. Of course we'd like it to be even higher. Today it looks like one of the biggest barriers to even create a coverage of treatment, is people not even knowing they're HIV positive. Remember that for most of the time the person is feeling healthy. That's why a lot of attention at the moment in increasing HIV testing rates. So treatment is a really wonderful life-saving medical innovation. But this story actually gets even better. With successful treatment, the virus cannot reproduce itself, and so the concentration of the virus in the blood reduces. With a lower concentration of virus in the blood, the HIV positive person is not only going to have an immune system recovers, but it's also going to be a lower chance of transmission. Mothers on treatment are much less likely to pass on HIV to their babies. But we did not know at first about same effect would be for reducing transmission to sexual partners. Then there was a landmark trial called HPTN 052, and that confirmed it. They randomized sexually active couples, and which one partner was HIV positive and the other was not, to either receive ART earlier than normally would or not. They found a more than 90 percent lower rate of transmission for the couples where the HIV positive partner was already on ART. When that news hit it made a real splash, people thought it could be the end of AIDS. After all, treatment that was already being successfully rolled out could contribute to reducing HIV incidence. But, it's a bit more complicated than that unfortunately. We'll get to that in the next lecture.
