High hopes for new TB vaccine trials
1 August 2009, 16:17
By Kanina Foss
IF HIV is the killer, then TB is its henchman. And a new TB vaccine - soon to be tested in Johannesburg - could be the thing to foil their collusion.
TB is the leading cause of death among people living with HIV in Africa. Seventy-three percent of South Africans infected with TB are also HIV-positive.
A new vaccine (AERAS-402/Crucell Ad35) could significantly advance the fight against TB in both HIV-positive and HIV-negative patients.
Health systems management organisation The Aurum Institute will conduct a trial in Johannesburg to determine the safety of the vaccine in HIV-positive adults. The trial will also provide the first indications of whether the vaccine is effective.
"If we find a vaccine, it will be a major contribution to helping reduce the risk to TB-infected, HIV-infected individuals, and for controlling TB in high HIV prevalence settings such as South Africa," said The Aurum Institute's CEO, Dr Gavin Churchyard.
If the vaccine was effective in HIV-positive people, it was likely that it would be even more effective in HIV-negative people, said Churchyard. They hope to start vaccinating next month.
The advantage of a vaccine over treatment is that it's easier to roll out on a large scale.
There's also no need to worry about adherence to chronic medication, or adverse drug interactions.
"We believe that an effective TB vaccine is the best hope for the achievement of the millennium goals for TB reduction and the eventual elimination of this scourge from our planet," said Churchyard.
The current vaccine, BCG, was developed more than 85 years ago.
It reduces the risk of severe forms of TB in early childhood, but is not very effective in preventing pulmonary TB in adolescents and adults - the populations with the highest rates of TB.
Preliminary clinical trial data has shown that the vaccine being tested by The Aurum Institute produces the highest levels of CD8 immune cells, a leading strategy in the pursuit of an effective TB vaccine.
AERAS-402/Crucell Ad35 was developed by Crucell, a biopharmaceutical company in the Netherlands, and is being funded by a non-profit organisation called the Aeras Global TB Vaccine Foundation.
It has previously been tested for safety on healthy adults in the US and South Africa, and on adults exposed to TB in South Africa and Kenya, but this is the first trial that will test safety in HIV-infected adults.
One of the reasons why the results of the trial will be important is because vaccinations are generally administered en masse.
"You don't want to have to worry about someone's HIV status," said Churchyard. Additionally, in low resource settings, many people do not know their HIV status. "We want to be sure that the vaccine doesn't cause HIV to progress more rapidly."
Volunteers in the trial will have already been infected with HIV and will be at high risk of acquiring TB.
"We hope that we will show it's safe, and that we will see the first glimpse of whether it may be effective," said Churchyard.
IF HIV is the killer, then TB is its henchman. And a new TB vaccine - soon to be tested in Johannesburg - could be the thing to foil their collusion.
TB is the leading cause of death among people living with HIV in Africa. Seventy-three percent of South Africans infected with TB are also HIV-positive.
A new vaccine (AERAS-402/Crucell Ad35) could significantly advance the fight against TB in both HIV-positive and HIV-negative patients.
Health systems management organisation The Aurum Institute will conduct a trial in Johannesburg to determine the safety of the vaccine in HIV-positive adults. The trial will also provide the first indications of whether the vaccine is effective.
"If we find a vaccine, it will be a major contribution to helping reduce the risk to TB-infected, HIV-infected individuals, and for controlling TB in high HIV prevalence settings such as South Africa," said The Aurum Institute's CEO, Dr Gavin Churchyard.
If the vaccine was effective in HIV-positive people, it was likely that it would be even more effective in HIV-negative people, said Churchyard. They hope to start vaccinating next month.
The advantage of a vaccine over treatment is that it's easier to roll out on a large scale.
There's also no need to worry about adherence to chronic medication, or adverse drug interactions.
"We believe that an effective TB vaccine is the best hope for the achievement of the millennium goals for TB reduction and the eventual elimination of this scourge from our planet," said Churchyard.
The current vaccine, BCG, was developed more than 85 years ago.
It reduces the risk of severe forms of TB in early childhood, but is not very effective in preventing pulmonary TB in adolescents and adults - the populations with the highest rates of TB.
Preliminary clinical trial data has shown that the vaccine being tested by The Aurum Institute produces the highest levels of CD8 immune cells, a leading strategy in the pursuit of an effective TB vaccine.
AERAS-402/Crucell Ad35 was developed by Crucell, a biopharmaceutical company in the Netherlands, and is being funded by a non-profit organisation called the Aeras Global TB Vaccine Foundation.
It has previously been tested for safety on healthy adults in the US and South Africa, and on adults exposed to TB in South Africa and Kenya, but this is the first trial that will test safety in HIV-infected adults.
One of the reasons why the results of the trial will be important is because vaccinations are generally administered en masse.
"You don't want to have to worry about someone's HIV status," said Churchyard. Additionally, in low resource settings, many people do not know their HIV status. "We want to be sure that the vaccine doesn't cause HIV to progress more rapidly."
Volunteers in the trial will have already been infected with HIV and will be at high risk of acquiring TB.
"We hope that we will show it's safe, and that we will see the first glimpse of whether it may be effective," said Churchyard.
- This article was originally published on page 7 of The Pretoria News on August 01, 2009
Johannesburg
