In January 2008, the US Food and Drug Administration (FDA) approved a new oral antiretroviral for the treatment of HIV. Etravirine, sold under the brand name Intelence™, is approved for treatment in combination with other anti-HIV medications in adults who have a history of resistance to multiple classes of drugs.
Manufactured by Tibotec Therapeutics, a division of Ortho Biotech, etravirine is a non-nucleoside reverse transcriptase inhibitor (NNRTI). NNRTIs help prevent T cells, a type of white blood cell that protects the body from infection, from becoming infected with HIV.
For HIV to infect a cell, it has to copy its genetic code into the cell’s DNA. This programs the cell to create new copies of HIV. Since HIV’s genetic material is in the form of RNA, its RNA must first be converted into DNA to copy the genetic code. HIV’s reverse transcriptase enzyme is needed to perform this process.
NNRTIs attach themselves to reverse transcriptase and prevent the enzyme from converting RNA to DNA. This keeps HIV’s genetic material from being incorporated into the healthy genetic material of the cell, preventing the cell from mass-producing the new virus. Etravirine is the first NNRTI to show antiviral activity in treatment-experienced adult patients with HIV resistant to an NNRTI and other antiretroviral agents.
“This is another significant new product for the many HIV-infected patients who are NNRTI-resistant and whose infections are not responding to currently available medications,” says Debra B. Birnkrant, MD, director of the FDA’s Division of Antiviral Products. In the past, resistance to one NNRTI meant resistance to all in the class of drugs.
The FDA’s approval of etravirine is based primarily on data from 599 adults who received the drug in two randomized, double-blind, placebo-controlled trials. After 24 weeks of treatment, more of the patients who received etravirine along with a new regimen that included another newer antiretroviral medication experienced reductions in the level of HIV in their blood than did those who received a placebo and the new regimen.
The most common side effects reported were rash, nausea, diarrhea and abdominal pain. These can be avoided by taking the drug with food. When speaking with a doctor about obtaining the drug, the FDA recommends disclosure of all current medications. This, along with complying with the interaction information included in the packaging, can help prevent potentially dangerous drug interactions.