July 17, 2012

HIV-prevention drug Truvada approved by FDA

US health regulators have for the first time approved a drug to prevent HIV infection.

People living with HIV take antiviral medications to control the HIV infection. Now, for the first time, Truvada can be used by adults who do not have HIV but are at high risk of infection and anyone who may engage in sexual activity with HIV-infected partners, said the Food and Drug Administration (FDA).

The FDA approved the new use of Truvada — to be taken once daily and used in combination with safer sex practices — to reduce the risk of sexually acquired HIV-1 infection in adults who do not have HIV but are at high risk of becoming infected. (HIV-1 is the most common form of HIV.)

Truvada is already used in combination with other drugs to treat HIV-positive patients. Produced by the California-based Gilead Sciences Inc., it is a combination of two antiretroviral medications — tenofovir disoproxil fumarate and emtricitabine - used to treat HIV.

When Truvada is used as a treatment for HIV rather than a preventive, the patient also takes a third drug. Which of the other approved HIV drugs is added depends on the needs of the patient, says Debra Birnkrant, M.D., director of the Division of Antiviral Products at FDA.

Before this medicine is prescribed, Birnkrant says there are several factors that a person and his or her health care professional must consider in weighing the risk versus the benefit:
  • The person must be tested to ensure that he or she is HIV negative.
  • Flu-like symptoms—such as fever or muscle aches—are a red flag because they could indicate the presence of early, acute HIV infection, even if test results are negative. There is a window of four to five weeks with some tests, and up to three months with others, in which the antibodies that indicate HIV infection do not appear in the blood.
  • Safety concerns tied to Truvada have to do with its effect on the bones and kidneys. While effects observed in clinical trials were mild and reversible with discontinuation of the medication, people with a history of bone or kidney ailments should be regularly monitored to ensure their continued health.
  • It is recommended that the person also be tested for hepatitis B because worsening of hepatitis B infections has been reported in those who have both HIV-1 and hepatitis B when treatment with Truvada was stopped.
Types of HIV drug treatment
  • Antiretroviral therapy - used to treat the infection, reduce the chance of onward transmission and prolong life
  • Post-exposure prophylaxis (PEP) - emergency treatment (within 72 hours of exposure) aimed at preventing infection shortly after exposure
  • Pre-exposure prophylaxis (PrEP) - medication taken to reduce or eliminate the chance of getting infected
Studies showed the drug reduced the risk of contracting HIV by up to 73%. However, some health workers and groups active in the HIV community have opposed its use as a preventive.

There have been concerns the circulation of such a drug could engender a false sense of security and mean people will take more risks. There have also been fears that a drug-resistant strain of HIV could develop.

In a statement, the FDA stressed that the drug should be used as part of a "comprehensive HIV prevention plan", including condom use and regular HIV testing.

In May, an advisory group of health experts recommended approval for the pill.

Studies from 2010 showed that Truvada reduced the risk of HIV in healthy gay men - and among HIV-negative heterosexual partners of HIV-positive people - by between 44% and 73%.

Michael Barton of UNAIDS, the Joint United Nations Programme on HIV/AIDS, said there was good trial evidence that the drug could significantly cut the risk of the infection being passed on, but only if the tablets are taken consistently.

Many of the men in the trials did not take the drug regularly enough to get the full protection.

He said that, in most circumstances, it would be better to treat the HIV-positive partner in the couple rather than focus on the HIV-negative one.

"We know that for HIV-positive people if they consistently take antiretroviral drugs and their viral load is suppressed for them it's almost impossible to transmit the virus."

Antiretroviral drugs will also prolong their life.

But he said the new drug might be useful in situations where, for example, a woman has a partner with HIV who is unwilling to take antiretrovirals or use condoms.

Truvada is approved in most other countries, including the UK, for the treatment of HIV, but not prevention.

  1. FDA's Consumer Updates: FDA Approves First Medication to Reduce HIV Risk. U.S Food and Drug Administration (FDA). 16th July, 2012. Available online at http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm311821.htm
  2. BBC News US & Canada (July 16, 2012). "HIV-prevention drug Truvada approved by US". BBC News. Available online: http://www.bbc.co.uk/news/world-us-canada-18863341

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