News / Africa

    US Scientists Expand Scope of HIV Vaccine Study

    Joe DeCapua

    The world’s largest ongoing HIV vaccine study has been expanded to consider multiple ways a vaccine might boost immune response to the AIDS virus. The U.S. Institute of Allergy and Infectious Diseases (NIAID) is testing the safety and efficacy of a dual vaccine candidate.

    It’s called the HVTN 505 study and has been underway since June 2009. HVTN stands for the HIV Vaccine Trials Network, which is funded by the National Institutes of Health.

    “The trial is being expanded both in terms of the number of participants, as well as what the trial is looking to answer,” said Mitchell Warren, head of AVAC, the AIDS Vaccine Advocacy Coalition, who’s following the study’s developments.

    Broader study

    Enrollment is increasing from about 1,300 to 2,200 participants.

    Originally, the study focused on whether the vaccine regimen could lower the amount of HIV in the blood if people were to become infected after being vaccinated. It did not focus on whether it could actually prevent infection. Now it does.

    The change stems in part from encouraging results in 2009 of the RV-144 vaccine trial in Thailand. The trial proved protection is possible, although the effectiveness was too low to go to market.

    Warren said, “Because of the Thai trial, what we saw in that vaccine actually preventing infection was, wow, we really need to then look differently at HVTN 505 and expand its ability to look at the question: could this vaccine actually also prevent infection, prevent acquisition of HIV?”

    Learning more, doing better

    In AIDS vaccine research in the 1980s and 90s, there really was little, if any, success in getting vaccine candidates to give a protective effect. So, the emphasis switched to whether vaccines could mitigate the infection.

    Warren says there are two basic immune system responses to infection.

    “We have the antibody response, or the humoral immunity, which conceptually is the part of the body that could help prevent infection. And then we have what’s called cell mediated immunity, which is the part of the immune system that will help modulate the disease if one were to be infected,” he said.

    The HVTN 505 study will now try to activate both of those systems.

    “It uses a prime boost combination of two different vaccines. One is a DNA vaccine that has snippets of HIV that can’t cause HIV at all, but is meant to kind of prime the immune system. And then it has an Adeno 5 vaccine boost,” said Warren.

    Adeno 5 is actually a common cold virus. It’s used as a vector or means of delivering the vaccine.

    Choose carefully

    All the participants in the study fall under the UNAIDS category of men who have sex with men, or MSM. The latest U.S. data show the group has a very high HIV infection rate, particularly young men of color.

    It’s important for medical studies to carefully choose a target group.

    “Every trial is unique and to the degree that a trial can ask a very specific question in a very specific population, the better we can answer the question. If we just created a vaccine trial or a treatment trial and said anybody can be in our trial, we just want bodies, at the end of the day we would look at the answer and say we don’t know what this means because these people were so different,” said Warren.

    The HVTN 505 study is being conducted in 12 U.S. cities. The executive director of the AIDS Vaccine Advocacy Coalition calls this the most exciting time in HIV vaccine research.

    The study is being led by Scott M. Hammer, M.D., the chief of NIAID’s Division of Infectious Diseases and the Harold C. Neu professor of medicine in the College of Physicians and Surgeons at Columbia University.

    You May Like

    Self-doubt, Cultural Barriers Hinder Cambodian Women in Tech

    Longtime Cambodian tech observer Sok Sikieng says that although more women have joined profession in recent years, there remain significant factors hindering women from reaching tech potential

    Trans-Adriatic Pipeline to Boost European Energy Security

    $4.5 billion-pipeline will become operational in 2020 and will deliver gas from Azerbaijan’s Shah Deniz II field to southern Italy

    Video California Celebration Showcases Local Wines, Balloons

    Annual festival showcases the region's harvested agriculture, fine wines and offers opportunities to experience the gentle breeze in a hot air balloon flight

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    By the Numbers

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Vietnamese-American Youth Optimistic About Obama's Visit to Vietnami
    X
    Elizabeth Lee
    May 22, 2016 6:04 AM
    U.S. President Barack Obama's visit to Vietnam later this month comes at a time when Vietnam is seeking stronger ties with the United States. Many Vietnamese Americans, especially the younger generation, are optimistic Obama’s trip will help further reconciliation between the two former foes. Elizabeth Lee has more from the community called "Little Saigon" located south of Los Angeles.
    Video

    Video Vietnamese-American Youth Optimistic About Obama's Visit to Vietnam

    U.S. President Barack Obama's visit to Vietnam later this month comes at a time when Vietnam is seeking stronger ties with the United States. Many Vietnamese Americans, especially the younger generation, are optimistic Obama’s trip will help further reconciliation between the two former foes. Elizabeth Lee has more from the community called "Little Saigon" located south of Los Angeles.
    Video

    Video First-generation, Afghan-American Student Sets Sights on Basketball Glory

    Their parents are immigrants to the United States. They are kids who live between two worlds -- their parents' homeland and the U.S. For many of them, they feel most "American" at school. It can be tricky balancing both worlds. In this report, produced by Beth Mendelson, Arash Arabasadi tells us about one Afghan-American student who seems to be coping -- one shot at a time.
    Video

    Video Newest US Citizens, Writing the Next Great Chapter

    While universities across the United States honor their newest graduates this Friday, many immigrants in downtown Manhattan are celebrating, too. One hundred of them, representing 31 countries across four continents, graduated as U.S. citizens, joining the ranks of 680,000 others every year in New York and cities around the country.
    Video

    Video Vietnam Sees Strong Economic Growth Despite Incomplete Reforms

    Vietnam has transformed its communist economy to become one of the world's fastest-growing nations. While the reforms are incomplete, multinational corporations see a profitable future in Vietnam and have made major investments -- as VOA's Jim Randle reports.
    Video

    Video Qatar Denies World Cup Corruption

    The head of Qatar’s organizing committee for the 2022 World Cup insists his country's bid to host the soccer tournament was completely clean, despite the corruption scandals that have rocked the sport’s governing body, FIFA. Hassan Al-Thawadi also said new laws would offer protection to migrants working on World Cup construction projects. VOA's Henry Ridgwell reports.
    Video

    Video Infrastructure Funding Puts Cambodia on Front Line of International Politics

    When leaders of the world’s seven most developed economies meet in Japan next week, demands for infrastructure investment world wide will be high on the agenda. Japanese Prime Minister Shinzo Abe’s push for “quality infrastructure investment” throughout Asia has been widely viewed as a counter to the rise of Chinese investment flooding into region.
    Video

    Video Democrats Fear Party Unity a Casualty in Clinton-Sanders Battle

    Democratic presidential front-runner Hillary Clinton claimed a narrow victory in Tuesday's Kentucky primary even as rival Bernie Sanders won in Oregon. Tensions between the two campaigns are rising, prompting fears that the party will have a difficult time unifying to face the presumptive Republican nominee, Donald Trump. VOA national correspondent Jim Malone has more from Washington.
    Video

    Video Portrait of a Transgender Marriage: Husband and Wife Navigate New Roles

    As controversy continues in North Carolina over the use of public bathrooms by transgender individuals, personal struggles with gender identity that were once secret are now coming to light. VOA’s Tina Trinh explored the ramifications for one couple as part of trans.formation, a series of stories on transgender issues.
    Video

    Video Amerikan Hero Flips Stereotype of Middle Eastern Character

    An Iranian American comedian is hoping to connect with American audiences through a film that inverts some of Hollywood's stereotypes about Middle Eastern characters. Sama Dizayee reports.
    Video

    Video Budding Young Inventors Tackle City's Problems with 3-D Printing

    Every city has problems, and local officials and politicians are often frustrated by their inability to solve them. But surprising solutions can come from unexpected places. Students in Baltimore. Maryland, took up the challenge to solve problems they identified in their city, and came up with projects and products to make a difference. VOA's June Soh has more on a digital fabrication competition primarily focused on 3-D design and printing. Carol Pearson narrates.

    Special Report

    Adrift The Invisible African Diaspora