[ad_1]
AMSTERDAM – HIV vaccine candidates produced immune responses that lasted at least a year after the last shot, a researcher said here.
The Randomized Phase I / IIa Analysis According to Frank Tomaka, MD, of the Janssen Promoter, The Johnson & Johnson Affiliate
The Results Obtained Suggestion That A "Mosaic" Vaccine Could Offer a "robust humoral and cellular response even after one year". Tomaka told reporters at the International AIDS Conference, but it is unclear whether additional booster shots would be needed.
Investigators will follow participants in the trial for another 5 years to see how the immune response changes
But Tomaka warned that it was still early for the vaccine: its effectiveness is not good. has not yet been demonstrated, although the durability is comparable to that seen in nonhuman primates where a Phase IIb study, dubbed Imbokodo (HVTN 705), is currently underway in Africa to test the effectiveness of the vaccine, using the most immunogenic candidates studied in APPROACH, he said. The results are expected in 2021.
Sustainability data, says Tomaka, were "key pieces of information" that were needed before the Imbokodo trial could be started.
In many diseases, the immune system is able to expel the pathogen, but there is no documented case of a person who has contracted HIV and who has it. cleared, setting the bar high for vaccine research.
The first partial success dates back nearly a decade. for a candidate vaccine, but with a very wide confidence interval (1.1% -52.1%). The RV144 test showed a positive signal, but especially the immune response of the vaccine candidate decreased relatively rapidly.
A follow-up trial, called HVTN 702, is underway in Africa after the vaccine candidate has been modified to enable it to target
But to counteract the diminishing immune responses seen in Thailand, investigators have added a additional dose of the test regimen, commented Linda-Gail Bekker, MBChB, Ph.D., of the Desmond Tutu HIV Center in Cape Town. Town, South Africa, which is one of the leaders in the study.
Ideally, she stated MedPage Today that a vaccine would protect against HIV without requiring many booster visits for booster shots. But the "first prize" is to get an effective vaccine, she said, and that must wait on the results of clinical trials.
Bekker, who is president of the International AIDS Society, who sponsors the biennial conference, moderated a
The main difference between vaccine candidates is that one that is tested by Bekker and his colleagues targets only the main vaccine variety circulating in southern Africa. If successful, it will need to be reconfigured for use in other parts of the world.
THE APPROACH / IMBOKODO, by contrast, is a "mosaic" – it contains antigens of all circulating strains, or clades, of HIV. "Our goal is to create a global vaccine," said Tomaka
in the study, 393 healthy seronegative volunteers were randomly badigned to two strokes of an adenovirus vector (Ad26 ) carrying the mosaic antigens. Three groups received two booster injections of the same construct and three groups received booster vaccines modified Ankara carrying mosaic antigens. One group received only the first two shots and one eighth group received a placebo
Several groups also got a final shot – a synthetic version of the HIV gp140 clade C protein – either in high or low in low doses. ] The best answers, said Tomaka, were obtained with two AD26 builds, followed by two boosters of the same substance, and a high dose of clade C protein. But all groups, the exception of those who received the placebo, showed durable responses
There were no serious adverse events related to the vaccine and none of them was grade 3 or 4.
The study is supported by Janssen. Tomaka says that he is an employee of Janssen, a Johnson & Johnson pharmaceutical company, and that he owns shares in Johnson & Johnson.
Bekker made no statement.
1969-12-31T19: 00: 00-0500
Last updated
Source link
