News / Africa

US Scientists Expand Scope of HIV Vaccine Study

TEXT SIZE - +
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

Multimedia Relatives of South Korean Ferry Victims Fire at Authorities

36 people are confirmed dead, but some 270 remain trapped on board More

War Legacy Haunts Vietnam, US Relations

$84 million project aims to clean up soil contaminated by Agent Orange More

Wikipedia Proves Useful for Tracking Flu

Technique gave better results than Center for Disease Control (CDC) and Google’s Flu Trends More

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

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Ukraine, Russia, United in Faith, Divided in Politicsi
X
Michael Eckels
April 19, 2014
There is a strong historical religious connection between Russia and Ukraine. But what role is religion playing in the current conflict? In the run-up to Easter, Michael Eckels in Moscow reports for VOA.
Video

Video Ukraine, Russia, United in Faith, Divided in Politics

There is a strong historical religious connection between Russia and Ukraine. But what role is religion playing in the current conflict? In the run-up to Easter, Michael Eckels in Moscow reports for VOA.
Video

Video Face of American Farmer is Changing

The average American farmer is now 58 years old, and farmers 65 and older are the fastest growing segment of the population. It’s a troubling trend signaling big changes ahead for American agriculture as aging farmers retire. Reporter Mike Osborne says a new report from the U.S. Census Bureau is suggesting what some of those changes might look like... and why they might not be so troubling.
Video

Video Donetsk Governor: Ukraine Military Assault 'Delicate But Necessary'

Around a dozen state buildings in eastern Ukraine remain in the hands of pro-Russian protesters who are demanding a referendum on self-rule. The governor of the whole Donetsk region is among those forced out by the protesters. He spoke to VOA's Henry Ridgwell from his temporary new office in Donetsk city.
Video

Video Drones May Soon Send Data From High Seas

Drones are usually associated with unmanned flying vehicles, but autonomous watercraft are also becoming useful tools for jobs ranging from scientific exploration to law enforcement to searching for a missing airliner in the Indian Ocean. VOA’s George Putic reports on sea-faring drones.
Video

Video New Earth-Size Planet Found

Not too big, not too small. Not too hot, not too cold. A newly discovered planet looks just right for life as we know it, according to an international group of astronomers. VOA’s Steve Baragona has more.
Video

Video Copts in Diaspora Worry About Future in Egypt

Around 10 percent of Egypt’s population belong to the Coptic faith, making them the largest Christian minority in the Middle East. But they have become targets of violence since the revolution three years ago. With elections scheduled for May and the struggle between the Egyptian military and Islamists continuing, many Copts abroad are deeply worried about the future of their ancient church. VOA religion correspondent Jerome Socolovsky visited a Coptic church outside Washington DC.
Video

Video Critics Say Venezuelan Protests Test Limits of Military's Support

During the two months of deadly anti-government protests that have rocked the oil-rich nation of Venezuela, President Nicolas Maduro has accused the opposition of trying to initiate a coup. Though a small number of military officers have been arrested for allegedly plotting against the government, VOA’s Brian Padden reports the leadership of the armed forces continues to support the president, at least for now.
Video

Video More Millenials Unplug to Embrace Board Games

A big new trend in the U.S. toy industry has more consumers switching off their high-tech gadgets to play with classic toys, like board games. This is especially true among the so-called millenial generation - those born in the 1980's and 90's. Elizabeth Lee has more from an unusual café in Los Angeles, where the new trend is popular and business is booming.
Video

Video Google Buys Drone Company

In its latest purchase of high-tech companies, Google has acquired a manufacturer of solar-powered drones that can stay in the air almost indefinitely, relaying broadband Internet connection to remote areas. It is seen as yet another step in the U.S. based Web giant’s bid to bring Internet to the whole world. VOA’s George Putic reports.
AppleAndroid