Atripla is made jointly by Bristol-Myers Squibb and Gilead Sciences, Inc.
Tenofovir (one of the components of Atripla) is currently the only medication in a class of HIV medications known as nucleotide reverse transcriptase inhibitors (NtRTIs). Emtricitabine belongs to a group of medications known as nucleoside reverse transcriptase inhibitors (NRTIs), and efavirenz belongs to a group of HIV medications known as non-nucleoside reverse transcriptase inhibitors (NNRTIs). Although these three medications come from different medication classes, they all work similarly. Atripla blocks a process that the HIV virus needs in order to multiply.
HIV (human immunodeficiency virus) is the virus that causes AIDS. Like other viruses, it must use a person's own cells to reproduce. However, HIV is a little different from many other viruses because it must first convert its genetic material from RNA to DNA. It is the DNA genes that allow HIV to multiply.
HIV converts its genetic material by using a special protein called the reverse transcriptase enzyme. To create DNA, this enzyme uses several different protein building-blocks.
Atripla works by tricking reverse transcriptase into thinking it is one of these protein building-blocks. However, it is just different enough that when used to create DNA, the medication actually stops the DNA from being made. Without DNA, HIV cannot multiply. Atripla is not a cure for HIV or AIDS, however. It can help stop HIV from infecting healthy cells in the body, but it does not help cells that have already been infected with the virus.