At Ground Zero of India's war on AIDS

[Guest guest]

At Ground Zero of India's war on AIDS

Shobha Warrier in Chennai

August 09, 2006

Pune and Chennai are two of the places where trials are on to

actualise the world's dream of a vaccine to prevent the deadly

Acquired Immunodeficiency Disease Syndrome.

Till date there is no cure for AIDS.

Experts have found that the much-publicised 'ABC' of preventive

measures -- Abstinence, Being faithful to one's partner and Condoms -

- are not hundred per cent satisfactory.

A preventive vaccine -- like the ones already developed for small

pox and diphtheria -- seems the only answer to this global threat.

The enemy

Why is modern science yet to find a vaccine for a virus that has

only nine genes?

To put things in perspective, the tubercular bacillus has around

3,000 genes.

There are two reasons.

Reason one: The virus is in the process of mutation all the time.

Reason two: The mutation differs from region to region. The HIV

virus seen in Indians is different from what you see in the United

States or Africa. And because of the ever-changing nature of the

virus, the human body cannot produce an antibody to kill it.

Though economic, social and ethical problems have also contributed

to scientists not being able to produce a vaccine, the most

compelling of all these reasons is scientific.

" We cannot use the live virus, " says Dr V D Ramanathan, the man in

charge of the AIDS vaccine trial at the Tuberculosis Research Centre

in Chennai.

" We tried using a dead virus, but a dead virus does not behave in

the same way as a live virus. So, now, the scientific community is

trying different approaches. One is to take a part of the genes and

put it in a career called vector -- which is a harmless bigger

virus -- and inject it in humans. "

Why India

Global efforts to invent an AIDS vaccine have been on from the very

early 1990s. When it was found that the virus' mutation differs from

region to region, it was decided to conduct research in various

regions of the world.

Now, simultaneous trials are on in 40 different places.

In collaboration with the International AIDS Vaccine Initiative, the

Government of India represented by the National AIDS Control

Organisation and the Indian Council of Medical Research came to an

agreement to set up the two trials now being funded in India.

The National AIDS Research Institute, Pune, and the Tuberculosis

Research Centre, Chennai, are the two battlegrounds of India's war

against AIDS.

In Pune, three genes of the HIV virus are being used for the trial.

The vaccine has been tested in Belgium and Germany; now it is being

tested in India.

The vaccine under trial in Chennai is designed by an ICMR scientist,

Shekhar Chakraborty from Kolkata.

" He has isolated the virus from Indian patients. Another important

thing is, he has taken six genes out of the nine from the virus, and

put them in a vector called Modified Vaccinia Ancara, " says Dr

Ramanathan. " The MVA was used as a vector in the smallpox vaccine in

countries like Turkey, so, the safety of the vector has been

proved, " he adds.

Why humans

" Usually what we do is first test the vaccine in a test tube, then

tissue culture, and then on small animals, " says Dr Ramanathan.

" But the HIV vaccine cannot be tested like that because it doesn't

have any effect on animals. Primates like monkeys can get affected

but doing primates research is very difficult because many are

endangered species. Even if we test on primates, the question arises

how much of it can be applicable to human beings. So, it is wiser to

have human trials, " he adds.

" We have tested (the vaccine) on animals like rabbits and rats to

see whether the vaccine harms animals -- because no vaccine can be

given just like that to human beings, " Dr Ramanathan explains.

The Research Centre has obtained clearances from several

organisations like the Scientific Advisory Committee, the

Institutional and National Ethics Committee, the Genetic Engineering

Approval Committee, and also the health ministry, to conduct human

trials.

At an informal level, the Community Advisory Board has also been

consulted.

The approvals took a year to get.

The test trials are a joint effort by the Research Centre and a non-

governmental organisation called YRG Care, which provides volunteers

for the tests.

The trial

There are three phases in the HIV vaccine trial.

The first phase -- done on 30 to 50 healthy, HIV-negative people --

looks primarily at safety. The secondary objective of the test is to

see whether it induces an immune response.

In the second phase, it is tested on about 300 people. The primary

objective is to double-check the safety of the vaccine, but whether

the vaccine produces an immune response in human beings and how much

of the vaccine should be used (dose titration) are also tested.

" Those who are identified as high risk group -- like sex workers,

drug users, etc -- are not used as volunteers in the first two

phases, " explains Dr Ramanathan.

In the third phase -- conducted on a group of more than 3,000

people -- half of the volunteers are from the low risk groups, and

the rest from the high risk groups.

Dr Ramanathan stresses that the volunteers are told what is at

stake. They are told " that what we try is only a vaccine candidate

and not a vaccine. So, we tell our volunteers not to indulge in high

risk behaviour. "

Phase One, which started in January this year, will culminate in

February 2008. It will take six more months for the data to be

analysed.

Another four years are needed for the Phase Two and Phase Three will

take even longer.

So, the trials may take about 20 years.

The volunteers

During the 18 months of Phase One of the trials, the volunteers,

whose identity is kept secret, have to visit the Research Centre 17

times; blood is drawn from them 14 times.

For each visit, they are given Rs 500, which amounts to Rs 8,500

over one-and-a-half years.

" This is not a very good sum, " agrees Dr Ramanathan. " It is only a

compensation and not an incentive. But if any mishap occurs, they

will be taken care of by the sponsors. They will also be given a

medical insurance for the trial period, " he adds.

Initially, the Research Centre and YRG Care spoke about the vaccine

trials at various places like corporate offices, colleges, etc. But

few people were willing to volunteer.

The Research Centre decided to brief the media in detail.

" What turned the tide was the media workshop and the articles that

appeared in newspapers, " says Dr Ramanathan.

" More than 300 people came to our centre but after counselling and

discussing with their families, 68 came for health screening. As we

are testing in two doses, 16 are enrolled and another 16 are now

being recruited (for Phase One). "

The volunteers are willing soldiers in the war on AIDS.

" One person came and told us, 'I know Bill Gates is giving a lot of

money for the HIV/AIDS affected. I don't have money to give. That is

why I am volunteering myself,' " says Dr Ramanathan.

" Another person told us, 'I am a member of the Blue Cross society

and against animal experimentation. That is why I am volunteering

myself.' Another person from a lower middle class family refused to

accept the Rs 500 given as compensation, " he continues.

" The primary motivation appears to be doing something for society.

Many have seen people dying of AIDS, " Dr Ramanathan adds.

" And, above all, they have understood that by participating in the

trial, they are not going to be infected. "

http://in.rediff.com/news/2006/aug/09spec.htm