Treatment Review, Spring 1998

The Network has reported regularly on clinical trial results of new anti-HIV treatments. These trials have shown that strong anti-HIV drug combinations can often lower the amount of virus in the blood (usually called the viral load), improve T4 cell counts, and reduce illness and disease progression in people with HIV.

Now that stronger anti-HIV drugs have been available by prescription for nearly two years, there have been many reports of the effects of these treatments in the real world, outside of clinical trials. Nationally in the USA, deaths from AIDS dropped by 44% in the first half of 1997 compared to the first half of 1996. In New York City during the same period, deaths fell by close to 50%. The state of California has reported an even more dramatic decline of nearly two thirds, from 2,788 in the first half of 1996 to 1,112 in the first half of 1997.

Several studies have also looked at the number of new opportunistic infections in people with AIDS since the approval of more powerful anti-HIV drugs. Johns Hopkins Clinic in Baltimore has reported that new cases of CMV (cytomegalovirus, an opportunistic infection that can cause blindness) fell by 81% in 1996. Mycobacterium avium complex (MAC) is another serious opportunistic infection that most commonly occurs in people with less than 100 T4 cells. A French study found that after the introduction of protease inhibitors in June 1996 only 7 new cases of MAC occurred in 700 people that they were collecting information on. Based on previous years, close to 100 cases of MAC would have been expected in this group of people.

A second French study of 59,256 people with HIV compared the number of opportunistic infections (OIs) diagnosed during the first half of 1996 to the number of OI cases diagnosed during the first half of 1997. There were fewer cases of every OI they looked at: cryptosporidiosis cases fell 82%, CMV 80%, MAC 73%, cryptococcal infection 70%, thrush 69%, PCP 68%, dementia 67%, Kaposi's sarcoma 65%, toxoplasmosis 64%, tuberculosis 50%, lymphoma 44%, bacterial pneumonia 41% and the rare brain infection PML by 28%. A similar American study from New Orleans found significant drops in the number of new cases of CMV, MAC, PCP pneumonia, wasting syndrome and Kaposi's sarcoma.

The overall message is that strong anti-HIV drug combinations can dramatically reduce serious illness and help people live longer. Drug side effects, inconvenience and actually remembering to take the drugs are all still a problem, but large reductions in the amount of HIV in the body are clearly linked to better health. Even when the viral load does not become "undetectable" (too low for the test to measure), reducing viral load can lead to improved health and survival.

It's important to realize this information does not mean that everyone that's HIV positive needs to start anti-HIV treatment immediately. Laboratory tests such as the T4 cell count and viral load are used to work out the risk of disease progression, to see if there's a need for treatment. The good news is that someone who is at risk for disease progression now has an excellent chance of preventing illness for a long time with anti-HIV treatment.

The good news described here is not just the result of lots of people having "undetectable" viral load. Many recent reports have found that even a short-term reduction in viral load can produce a long term improvement in health and increase in T4 cell count. Even studies of people for whom anti-HIV treatments seem to be failing (their viral load is increasing despite anti-HIV treatment) are not finding a lot of new illnesses and deaths. Researchers are not quite sure what this means, but there seem to be two theories. It may be that when HIV mutates to become resistant to combination anti-HIV treatment, it's less able to cause damage to the immune system. It's also possible that the immune system can benefit a great deal from even small and short-term reductions in levels of HIV. For example, having a 90% drop in viral load for three months may help the immune system control HIV better for another year or two after the HIV levels increase again. This is like rewinding the clock on the disease process, and some study results suggest that this can happen.