The Search for a Cure

HIV is so difficult to cure because the virus persists inside stable reservoirs that cannot be detected by the immune system.

This animation, created in collaboration with TED Ed, provides an introduction on HIV and AIDS and antiretroviral therapy, and provides a brief explanation of why HIV has been so difficult to cure.

Antiretroviral Therapy

Management of HIV/AIDS is achieved using combinations of antiretroviral drugs. There are numerous classes of drugs that target different aspects of the HIV life cycle, and therapy always involves taking two or more classes of drugs in combination.

The most commonly prescribed drugs include those that prevent the viral genome from being copied and incorporated into the cell’s DNA. Other drugs prevent the virus from maturing, or block viral fusion, causing HIV to be unable to infect new cells in the body.

Antiretroviral therapy is highly effective at managing the levels of HIV. Continued use has been shown to keep HIV-infected individuals from ever progressing to AIDS, and can lower the viral count to nearly undetectable levels. With antiretroviral therapy, most people can expect to live long and healthy lives.

Unfortunately, antiretroviral therapy is not a cure for HIV. This is due to HIV’s ability to hide its instructions inside of cells where drugs cannot reach it.

During the HIV life cycle, HIV incorporates itself into its host cell’s DNA. Antiretroviral therapies can stop new viruses that might be produced from infecting new cells, but can’t eliminate the viral DNA from the host cell’s genome.

Most host cells will be killed by infection or will eventually die of old age, but a very small number of cells appear to live for a very long time in the body. Every so often, the viral DNA can get turned on, and the cell starts to produce new virus. This is why medication adherence is critical. Stopping medication, even for a short time, might result in new cells being infected with HIV.

Researchers are working hard to find a true cure for HIV that could completely eradicate the virus from an infected person.  Current directions include finding a means to activate cells that are harboring viral DNA, forcing them “out into the open” where they can then be targeted by antiretroviral drugs.  Researchers are also looking into ways of using genetic tools to delete viral DNA from the cell’s DNA.