The HIV vaccine under development at AIIMS is one of three vaccines being worked on by Indian researchers. But progress, unsurprisingly, has been slow. After all, the world has been working on an AIDS vaccine for two decades, but has little to show for it.
India already has two vaccines approved for Phase I human trials: the Adeno-Associated Virus vaccine and Modified Vaccinia Ankara (MVA) vaccine.
But no vaccine offers complete protection. "At best, AIDS vaccine offers only 50 per cent protection against the transmission of the HIV virus but mathematical models indicate that even half protection will reduce both transmission and viral load drastically," says Dr N. K. Ganguly, Director General, Indian Council of Medical Research (ICMR).
These vaccines target the HIV-I subtype C strain, which causes infection in over 90 per cent of the people living with HIV/AIDS in India. "Phase I trials for our first vaccine, which have been developed by the ICMR in tandem with the Ministry of Health and the International AIDS Vaccine Initiative (IAVI), will begin at the National AIDS Research Institute in Pune at the end of this year," said minister of health Dr Anbumani Ramadoss. Human trials of the MVA vaccine will begin in the middle of 2005.
"The ICMR is simultaneously developing two preventive vaccines and we will get to know whether they work or not in the next three years once they enter extended Phase II trials, where their efficacy (effectiveness) is tested on patients," says Dr Ganguly.
The first phase will involve 40 healthy adults and will go on for a year. If the immune responses to the vaccine are satisfactory, the trial will progress to the second and third phases. In these phases, the effectiveness of the vaccine is tested on patients who have developed AIDS. A highly effective AIDS vaccine should elicit a combination of immune responses: first, broadly neutralising antibodies to block HIV from entering cells; second, inducing cell-mediated immune responses to destroy the cells that HIV manages to enter.
"Vaccine-development is a long process and I don't see an AIDS vaccine hitting the market in the next eight to 10 years," says Dr C. M. Gulati, editor, Monthy Index of Medical Specialties, who is also a watchdog for human trials of drugs and vaccines in India.
Another prototype of the Candidate Vaccine for AIDS is being developed at the National Jai Vigyan Science & Technology Mission of the Department of Biotechnology.