A new Ugandan study offers great hope for people with AIDS in rural areas in Africa needing antiretroviral treatment.
The trial tested a model in which lay-trained counsellors, not doctors or nurses, treated people at home – and they were as healthy as the patients being treated in clinics.
The cluster randomised trial took place in 44 areas in Jinja, Uganda.
The results, published in the Lancet journal online this week, suggested: “This home-based HIV-care strategy is as effective as is a clinic-based strategy.
“(This) could enable improved and equitable access to HIV treatment, especially in areas with poor infrastructure and access to clinic care.”
The researchers found after two and a half years that:
*Home-based ART by trained lay workers achieved equal health gains;
*Reduced mortality, hospital admission and viral supression were used to measure health gains;
*Patient costs were cut by half or more in the home-based care;
*Home-based care cost the health service slightly less.
Supporting the model, an editorial in Lancet stated: “This result provides compelling evidence for rolling out home-based ART to complement facility-based delivery and facilitate access.
“(This is true) especially in rural settings with weak health systems, shortage of clinical staff , and poor patients for whom transport cost and lost work-time provide obstacles to treatment initiation and adherence.”
The results are exciting but Uganda has one huge advantage over South Africa. Stigma around HIV/AID is far less prevalent and people are much more open about having the virus.
Six years ago there were no TB vaccines in trials and now there are 13 being tested in sites or clinics, Dr Jerald Sadoff, MD of the Aeras Global TB Vaccine Foundation, said this morning at AIDS Vaccine 2009 in Paris.
Now four AERAS-sponsored trials are currently taking place in Africa with two more in the pipeline for 2010.
UCT’s TB Vaccine Initiative (SATVI) with a human clinical trial site in Worcester and the Aurum Health Institute in Johannesburg are among its international partners currently engaged in trials.
Sadoff, who has been involved in the successful development of many vaccines, said that in Worcester: “On 15 July 2009 the first baby was vaccinated (with a new TB vaccine) in more than 80 years.”
He told the HIV vaccine researchers: “TB and HIV live together and they are an unholy marriage that is killing people. We do not like this and would like them to get a divorce.”
TB kills 1.77 million people per year and infects 9.27 million people around the world: nearly half a million those deaths and 1.5 million of these infections are among people with HIV, mostly in Southern Africa.
The death rate is much higher among people with drug-resistant forms of TB.
The existing TB vaccine, BCG, is among the most widely used vaccines in the world yet it is probably one of the most ineffective, Sadoff observed.
BCG, a routine vaccination for babies, is not safe for infants who are HIV positive.
Despite its limitations, Sadoff said, BCG still prevents about 70 000 deaths a year by playing a role in stopping the spread of TB among children.
US scientist Louis Picker announced encouraging results from a big monkey trial at AIDS Vaccine 2009 in Paris this morning.
The study found that 54% – 13 of the 24 rhesus macaques monkeys infected with SIV – showed complete control of infection after an initial viral “blip”.
And significantly for vaccine researchers, this research identified the type of immune cells with the capacity to completely suppress the monkey version of HIV (known as SIV).
The effector memory T-cells (CD8+ T-cells) seem to be powerful at blocking SIV at the early stage of infection as the virus enters the body.
This is a critical time for the body’s immune defence against HIV, as Dr Alan Bernstein, executive director of the HIV Global Vaccine Enterprise, explains: “It looks like the body has a narrow window of opportunity to stop HIV of hours up to a day or two.”
Picker said the cytomegalovirus (CMV) was known to be the best at triggering effector site-based T-cells. His team made three versions of a SIV vaccine using a modified form of CMV as the vector (vehicle to take virus particles into the body).
The form of CMV he used was replication competent vector (which means it can copy itself) and so far only non-replicating vectors have been used in human trials since they are safer.
Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said scientists did not know if a non-replicating vector could produce these results and this was the “big punch” in Louis’s results.
A smaller study of this last year found that his type of vaccine protected a third of the 12 monkeys on which it was tested.
The results announced today are more significant since it is a bigger trial and all three groups showed “robust” responses, confirming that effector memory T-cells are providing protection (are the correlates of protection).
Picker said: “The effector memory control was abrupt (immediate), seemingly stable and correlates to CD8+ T-cells.”
The way in which the immune responses protect the body is a major, and complex, question for HIV researchers.
Bernstein said: “This reseach is very important for two reasons: understanding the correlates of protection is critical and we should be looking to see if effector memory T-cells were activated in the Thailand and STEP trials.”
Scientists do not yet know how the RV144 vaccine tested in Thailand provided partial protection (31%). The standard assays (lab tests) they do to test immune strength were discouraging yet the vaccine had some positive results – so they must now discover why.
Picker said an effective vaccine could combine neutralising antibodies, plus a CMV vector, and prime-boost vaccine (to boost the effect).
He is director of the vaccine programme at the Oregon Health and Science University’s Vaccine and Gene Therapy Institute in the US.
The Phambili study recruited 801 volunteers before it was halted and most of them were under 25 years old. Men and women were roughly equal in number.
Most of the men and women reported having one sexual partner and about half reported having unprotected penetrative sex.
About half of the men and women did not live with their main partner (were apart regularly).
Nearly half of the men also reported having casual, anonymous partners (with women this was about 11%) and about 40% said they drank or had drugs with sex (with women this was about 11%).
The only significant predictor of time to HIV infection was among men who had reported sexually transmitted infections at screening for the trial.
Dr Glenda Gray, director of the Wits Perinatal HIV Research Unit, today presented an “interim efficacy” analysis of data collected in the South African Phambili HIV Vaccine study.
This human clinical trial was halted in September 2007 due to futility (not showing efficacy) found in its companion study known as the STEP study. Both these trials were set up to test the same vaccine, the Merck Adenovirus 5, in uninfected adults.
Concern was raised at the time that uncircumcised men, who had pre-existing immunity to the Adenovirus 5, could be at slightly raised risk. But subsequent analysis of the STEP and Phambili data and follow up presented today showed that this was not in fact associated with increased risk of being infected. In the Phambili trial less than 20% of the participants had no pre-existing immunity to Ad5.
The trial was run in five provinces in South Africa with sites in Gauteng, North West, KwaZulu-Natal and the Western Cape and patients were followed up after September 2007 (data was frozen in August 2009).
Among the major findings that Gray presented were:
*This vaccine did not protect against HIV and there were no difference in new infections between the vaccine and placebo groups by the time of the first vaccination;
*But good cross clade immune reactivity was demonstrated: the vaccine being tested was a sub-type B candidate in an area where sub-type C is most common, but this finding shows at four weeks after two injections most volunteers had developed an immune response to both clades B and C (for clade C the response rate was 77%);
*A reduction in HIV viral load among the women who received the vaccine: 0.57 log reduction in viral load at the set-point (measured at the start of the study);
*early differences in CD4 decline between the vaccine and placebo participants: CD4 counts indicate immune strength so a slower decline is advantageous and over 12 months the vaccine group experienced this benefit but it was not sustained over time;
*Risk reduction behaviour was sustained over time; and
*Good uptake of male circumcision post-enrolment of about 32%: medical male circumcision reduces the risk of a man acquiring HIV by about 60% many studies have proved.
The new HIV infection rate that Gray reported was roughly 4% – about 10 to 20 times higher than the infection rate in the Thailand trial which was conducted among a low-risk population.
The number of vaccinations received did not impact on the probability of acquiring HIV (no statistical difference was found). During the trial 60 volunteers were infected – 40 of them were women.
Two-thirds of the volunteers got two vaccinations and a quarter got only one shot before the trial was suspended.
The long-awaited full results of the Thailand RV144 vaccine trial, presented at AIDS Vaccine 2009 in Paris this morning, yielded nothing unexpected.
The data and report, published in The New England Medical Journal today, confirmed what is already known: the vaccine had a modestly protective effect (31% efficacy compared to the placebo), was safe and well tolerated.
The trial investigators stood by their announcement last month that the effect was statistically significant – which has been a topic of much controversy in the last few weeks. One of their main points was that the statistics should be measured against the design of the trial and they explained why.
Colonel Nelson Michael, director of the US Military HIV Research Program, who presented along with Supachai Rerks-Ngarm, from the Thai Ministry of Health, Thailand, said: “This is the first evidence that a prime-boost HIV vaccine regimen may prevent infection and represents a significant step forward for vaccine research.
“While it will not likely have any immediate public health benefit, we are hopeful that the findings will guide additional studies and accelerate research efforts toward a more effective vaccine.”
Scientists at the plenary commented that the cellular immune results, released today, were what they had anticipated, and that important antibody tests had not yet been done so they could not comment on the vaccine’s ability to boost the humoral immunity (antibody immunity).
In summary, researchers still have no immunological clues as to why this vaccine was partially successful and this is one of the major questions that they will investigate now.
On the other hand, much of the data Dr Glenda Gray, director of the Wits Perinatal HIV Research Unit, presented from the interim analysis of the Phamibili study in South Africa (which was suspended in September in 2007 for showing no effect) was made public for the first time.
The AIDS vaccine conference in Paris next week will attract worldwide attention after the release last month of the encouraging results of the Thai vaccine trial.
The full results of the trial – which found infection rates were nearly a third (31%) lower among volunteers who received the vaccine than those who received the placebo – will be scrutinised at AIDS Vaccine 2009.
Questions have been raised about the study’s confidence intervals and how two ineffective vaccines produced a significant result. These questions are sure to be answered, although the details about how the vaccine works will take longer.
Another exciting issue on the agenda is the role of antibodies and scientists, including South African delegates, will be presenting the latest research on new antibodies.
The first AIDS vaccine conference was held in Paris in 2000 and the organisers of this year’s conference – the French National Agency for Research on AIDS and Viral Hepatitis and the Global HIV Vaccine Enterprise – say on their site is is “more evident than ever that a strong emphasis on basic research, within a creative and interdisciplinary context, is essential to find an effective vaccine to protect against HIV”.
I’m flying to France tomorrow night to cover the conference and will provide updates on this blog.
Stories don’t always live up to their promise. But the inauguration of the Wits Ndlela Research and Clinical Trials Unit in Bushbuckridge (now the Bohlabelo district) in rural Limpopo yesterday exceeded expectations.
Ndlela truly is a first-class scientific site in the middle of nowhere or, to be more precise, on edge of the Kruger National Park and Mpumalanga.
After landing at the Kruger Mpumalanga International Airport early morning, we drove nearly two hours – though only 100km – past citrus, banana and timber plantations, a cellphone mast and a No Stress Barber shack.
The tar road turned into a corrugated mud road which becomes impassable in heavy rains. Villagers living there cannot access health care or any other services in a hurry, even in emergencies.
Despite this, top Wits scientists led by Dr Eftyhia Vardas with partners from Italy are committed to doing research here. Equally impressive, they have the machines and lab needed to conduct clinical trials – at the highest international standards – into HIV, TB and other infectious diseases.
They will focus on the impact of these diseases in the local communities as well as ways to prevent them, for example, vaccines.
They have already started a PIME (prevalence, incidence and molecular epidemiology of HIV) study in the community, who seem supportive of the project.
Ndlela will build on demographic surveillance data collected annually in Agincourt (a subdistrict of Bohlabelo) for the past 16 years by the Wits/Medical Research Council Rural Public Health and Transitions Research Unit.
Ndlela is a new unit, funded by grants, of the Wits Faculty of Health Sciences.
Stefano Butto, director of Italy’s National Aids Center (a partner of Ndlela) and Derek Hanekom, the deputy minister of Science and Technology, were among those excited to be at the inauguration.