Health Encyclopedia


Health Encyclopedia Home

New Clues to How Long-Term Drug Therapy Keeps HIV at Bay

New Clues to How Long-Term Drug Therapy Keeps HIV at Bay

TUESDAY, Nov. 26, 2013 (HealthDay News) -- A new study suggests that the replication of HIV may slow or stop altogether in patients who are on long-term treatment, although remnants can still lurk in the body.

And the researchers now suspect that the virus is especially weak in those people who started treatment immediately after becoming infected.

The study is very small, involving just eight patients. However, the findings add more evidence to the debate over how soon patients should begin drug treatment after they're diagnosed as being infected with HIV. One of the study authors is ready to say that treatment must begin immediately.

"Patients should be started on therapy as soon as they are diagnosed to prevent the virus from hiding in large numbers of cells," said the researcher, Sarah Palmer, deputy director of the Center for Virus Research at Westmead Millennium Institute for Medical Research, in Australia. "Diagnosing HIV infection early and initiating therapy immediately is crucial for limiting the number of cells containing HIV."

While doctors can use drugs to kill the AIDS virus in the body, it's impossible to eliminate it completely. That means there's no cure for HIV infection or AIDS, the potentially deadly condition that the virus causes.

But what does the virus do when a patient is on medication -- does it keep replicating [making copies of itself] or does it hide? The authors of the new study sought to find an answer by analyzing immune-system cells taken from eight HIV-infected patients. All had been taking anti-HIV drug treatment for years.

This combined drug treatment is known as antiretroviral therapy (ART).

The researchers analyzed the cells and found that drug treatment appeared to stop the virus from replicating -- an important finding that suggests a possible weakness. However, HIV didn't vanish but instead hid in certain types of immune-system cells known as "resting memory T cells." These cells "remember" how to fight a particular body invader, such as a germ or virus and sit around waiting for it to return.

"These cells can remain dormant for many years even though they are carrying HIV," Palmer said. "When these cells start to replicate or are stimulated to replicate as part of our normal immune response, they also produce HIV, keeping the virus viable. Essentially, these cells are a ticking time bomb in patients, and once they are ignited they explosively produce HIV."

This finding confirms previous research showing that the lurking virus is "very stable for years," said David Schaffer, director of the Berkeley Stem Cell Center at the University of California, Berkeley. "It means that treatments must be developed to directly eliminate this long-lived pool, which is challenging," said Schaffer, who is familiar with the study's findings.

However, there's some good news. The numbers of these cells were smaller in patients who had started treatment soon after being diagnosed instead of waiting until they began to show symptoms.

"Diagnosing HIV infection early and initiating therapy immediately is crucial for limiting the number of cells containing HIV," Palmer said. "The scientific community must develop better strategies to flush HIV from its hiding place in patients without causing new infections."

Schaffer agreed. A treatment can't just halt the virus from growing in the body and wait for the infected cells -- the "latent pool" -- to die out, he said. "Finding a cure for HIV means that therapies must be developed to directly eliminate the latent pool of virus."

The study will appear online in this week's issue of the Proceedings of the National Academy of Sciences.

More information

For more about HIV/AIDS, try the U.S. National Library of Medicine.

SOURCES: Sarah Palmer, Ph.D., associate professor and deputy director, Center for Virus Research, Westmead Millennium Institute for Medical Research, New South Wales, Australia; David Schaffer, Ph.D., professor, chemical and biomolecular engineering, and bioengineering, Helen Wills Neuroscience Institute, and director, Berkeley Stem Cell Center, University of California, Berkeley; Nov. 25-29, 2013, Proceedings of the National Academy of Sciences

Related Items
Wellness Library
  What You Need to Know About AIDS
  HIV Prevention Is Still Important
Content Type 134
  HIV/AIDS and Skin Conditions
  Dealing with Discrimination When You Have HIV
  When You’re HIV-Positive: What to Say
  Disorders of the Immune System
  AIDS-Related Malignancies
  Preventing Opportunistic Infections in HIV/AIDS
Drug Reference
  Somatrem, Recombinant, rh-GH
  Emtricitabine; Tenofovir
  Abacavir; Lamivudine, 3TC
  Efavirenz; Emtricitabine; Tenofovir
  HIV/AIDS and Seniors Quiz
Daily News Feed
  Researchers Describe 1st 'Functional Cure' of HIV in Baby
  Survival Picture No Better for Patients With HIV-Related Lymphoma: Study
  Rapid Test Detects HIV-1 and HIV-2 Antibodies and HIV-1 Antigen
  New Drug Approved to Treat HIV-1
  HIV Patients Get a Mental Lift From Exercise, Study Finds
  Early Course of HIV Therapy May Give Infants a Break From Drugs
  U.S. Circumcision Rates Drop by 10 Percent: CDC
  For Uninfected Partner, Antiretroviral Drugs May Shield Against HIV
  'Intensified' Global Effort Needed to Further Cut Child Deaths: Report
  Nail Fungus Drug Might Help Against HIV, Study Suggests
  AIDS Virus in Cats Might Help Human Vaccine Effort, Study Hints
  Meds That Prevent HIV Infection Don't Spur Risky Behavior: Study
  Immune Protein Found to Block HIV Spread in Some People
  Scientists Uncover Breast Milk's Potential Secret Weapon Against HIV
  Counseling With HIV Testing May Not Help Prevent Future STDs
  Some 'High-Risk' Kidneys May Be Safe for Organ Transplant: Study
  Big Strides in Battle Against Pediatric AIDS
  Mother-Daughter Team Preaches the Gospel of HIV Prevention
  Child 'Cured' of HIV Remains Free of Virus, Doctors Report
  Early HIV Treatment a Win-Win, Researchers Report
  HIV Resistance Mapped by Gene Researchers
  Bisexual Men Aren't at Greater HIV Risk: Review
  Talking Openly With Partner Linked to HIV Testing in Teens
  Multivitamins May Help Fight HIV Progression, Study Suggests
  Unprotected Sex On the Rise Among U.S. Gay Men, CDC Says
  New HIV Strain May Move to AIDS More Quickly: Study
  Taking Drug to Prevent HIV Doesn't Seem to Encourage Risk-Taking
  Abused Women Vulnerable to Unsafe Sex Practices
  Many Young Americans With HIV Delay Treatment: Study
  Only 1 in 3 HIV-Infected Black Americans Gets Effective Treatment: Study
  Higher HIV Infection Rates Seen in Mental Health Patients: Study
  Kids' Checkups Should Include Cholesterol, Depression Tests, Doctors Say
  Kids Born With HIV May Face Heart Risks Later, Study Suggests
  Long-Acting HIV Drug May Offer Better Protection Against Infection
  Gene Therapy for Controlling HIV Shows Early Promise
  Doctors Cautiously Optimistic About 'Cure' for HIV-Infected Babies
  Vaginal Gel Might Prevent HIV Hours After Exposure
  HIV Transmission Between Women Rare, But Possible: CDC
  Hepatitis C Patients With HIV May Face Higher Risk of Liver Disease
  Study Adds to Signs Linking HIV to Heart Trouble
  HIV-Positive Inmates Benefit From Drug Treatment, Study Says
  Driving Ability May Falter With Age in HIV-Positive Adults
  Scientists Map DNA of Deadly Fungus
  Slightly Higher Risk of Birth Defects Seen in Pregnant Women on HIV Drugs
  CDC Urges Anti-HIV Pill for People at High Risk of Infection
  Kids More Likely Than Adults To Be Resistant to HIV Meds: Study
  Many Unaware of Their HIV Status Until It's Advanced
  Study: Common HIV Drug May Boost Suicide Risk
  HIV Prevention Drug Truvada Might Lower Genital Herpes Risk, Too
  HIV Patients Less Likely to Get Cancer Treatment: Study
  Mississippi Girl Thought Cured of HIV Shows Signs of Infection
  AIDS Epidemic May Be Subsiding: Report
  Those With HIV Living Longer, International Study Finds
  Many Sexually Active U.S. Teens Not Tested for HIV: CDC
  HIV Diagnoses Down in U.S., Except for Young Gay Males: CDC
  Animal Experiments Shed Light on HIV's Ability to Hide
  Scientists Snipped HIV Out of Human DNA
Adult Diseases and Conditions
  HIV and AIDS
Pediatric Diseases and Conditions
  Acquired Immune Deficiency Syndrome (AIDS)/Human Immunodeficiency Virus (HIV)
  AIDS/HIV in Children