NIAID will not move forward with the PAVE 100 HIV Vaccine Trial

Jul 17, 2008

After soliciting and considering broad input from the scientific and HIV advocacy communities, the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), has determined that it will not conduct the HIV vaccine study known as PAVE 100.

However, NIAID believes the vaccine developed by its Vaccine Research Center (VRC) is scientifically intriguing and sufficiently different from previously tested HIV vaccines to consider testing it in a smaller, more focused clinical study. Therefore, NIAID will entertain a proposal for an alternative study with one specific goal: to determine if the vaccine regimen significantly lowers viral load—the amount of HIV in the blood of vaccinated individuals who may later become infected with HIV.

The original PAVE 100 study, as presented to NIAID's AIDS Research Advisory Committee in January 2007, proposed to test the VRC's HIV vaccine regimen in a trial initially designed to enroll 8,500 volunteers in the United States, South America, the Caribbean and Eastern and Southern Africa. The study was to begin U.S. recruitment in October 2007 but was postponed last fall following the decision to halt immunizations in the STEP HIV vaccine study. That decision was made after it was determined that the vaccine used in the STEP trial, an investigational product developed by Merck & Co. Inc., failed to prevent HIV infection or reduce viral load.

Subsequent analyses of the STEP trial found increased numbers of HIV infections among those volunteers who received the vaccine in comparison to those who received the placebo; the Merck vaccine itself did not cause HIV infection. The highest risk of HIV infection among vaccinees compared with placebo recipients appeared to be among males who were both uncircumcised and had pre-existing neutralizing antibodies to adenovirus type 5 (Ad5), the common cold virus used in the vaccine as a carrier for the HIV genes. Vaccination resulted in no apparent increased risk in men who were circumcised and who lacked pre-existing neutralizing antibodies to Ad5. The VRC vaccine regimen that was to be tested in the PAVE 100 study has two components, one of which includes an Ad5-based carrier, which is administered to boost immune responses that are first stimulated with a DNA vaccine.

Based on the analyses of the STEP study results, PAVE 100 was redesigned and reduced somewhat in its proposed scope, although it remained a scientifically and logistically complex study. The redesigned PAVE 100 study would have involved testing the VRC vaccine in 2,400 U.S.-based, circumcised men who have sex with men and who lack preexisting neutralizing antibodies to Ad5. The redesigned study would have tested the vaccine's effect on viral load, provided additional safety information about the product, and examined in detail immune responses to the vaccine and their impact on viral load.

Based on the available scientific information, NIAID has decided that the VRC vaccine regimen did not warrant a trial of this size and scope and that PAVE 100 will not proceed. However, NIAID will entertain a smaller, more focused clinical trial designed to answer one important question: Does the product have a significant effect on HIV viral load? If such an effect is noted, then additional studies or expansion of the study to carefully examine immunological correlates could be performed. NIAID will consider such an alternative study and will announce its decision at a later time.

Source: National Institute of Allergy and Infectious Diseases

Explore further: So much has changed since the first HIV test was approved 30 years ago

add to favorites email to friend print save as pdf

Related Stories

Why your laptop battery won't kill you

1 hour ago

News on Tuesday that major U.S. airlines are no longer going to ship powerful lithium-ion batteries might lead some to fret about the safety of their personal electronic devices.

Visa, MasterCard moving into mobile pay in Africa

1 hour ago

Americans may just be getting used to mobile pay, but consumers in many African countries have been paying with their phones for years. Now payment processors Visa and MasterCard want to get a slice of that market, and are ...

Lightning plus volcanic ash make glass

1 hour ago

In their open-access paper for Geology, Kimberly Genareau and colleagues propose, for the first time, a mechanism for the generation of glass spherules in geologic deposits through the occurrence of volcan ...

Recommended for you

Obese British man in court fight for surgery

Jul 11, 2011

A British man weighing 22 stone (139 kilograms, 306 pounds) launched a court appeal Monday against a decision to refuse him state-funded obesity surgery because he is not fat enough.

2008 crisis spurred rise in suicides in Europe

Jul 08, 2011

The financial crisis that began to hit Europe in mid-2008 reversed a steady, years-long fall in suicides among people of working age, according to a letter published on Friday by The Lancet.

New food labels dished up to keep Europe healthy

Jul 06, 2011

A groundbreaking deal on compulsory new food labels Wednesday is set to give Europeans clear information on the nutritional and energy content of products, as well as country of origin.

Overweight men have poorer sperm count

Jul 04, 2011

Overweight or obese men, like their female counterparts, have a lower chance of becoming a parent, according to a comparison of sperm quality presented at a European fertility meeting Monday.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.