A team from the Delhi-based National Institute of Immunology is working on developing an immuno-contraceptive vaccine designed to curtail the stray dog population.
Stray dog menace is a major concern in every urban centre of the country, including Bangalore. India also reportedly has the highest incidence of rabies in the world. The injectable contraceptive vaccines will generate antibodies that make female dogs infertile.
The research on the vaccine began with the intention of using it on humans. However, two limitations led researchers to shift from the original target species.
“We saw a big logistic problem in introducing the vaccine for human use. There was no 100 per cent efficacy; no vaccine can provide that. So, if there was even one failure, it would have caused a big problem,” said Dr Satish Gupta, deputy director, National Institute of Immunology.
Gupta was in Bangalore recently for the first Dr T C Anand Kumar Memorial Symposium. The antibodies’ response to the vaccine varied from woman to woman. To ensure that the vaccine is effective, a continuous monitoring system has to be set up and that is a costly proposition.
Hence, the group thought of using the vaccine on animals as it could be administered at the community level. Even if there were a few failures, there would be a decrease in the animal population in the course of time. However, he cautioned that the vaccine was not for domestic dogs, as that dealt at an individual level.
Since there were 2.5 lakh stray dogs in Delhi which needed to be sterilised, the team decided to conduct the vaccine trial on them. “The current surgical method of sterilisation is expensive. The vaccine will be considerably cheaper. Since it is a non-surgical method, it will also address the concerns of animal lovers,” Dr Gupta reasoned.
Working with Indian Immunologicals Ltd, a pharmaceutical public sector undertaking, for the last three years, the Institute produced successful results in its clinical studies.
However, the hurdle came in the form of the Review Committee of Genetic Manipulation (RCGM), the regulatory body under the Department of Bio-technology. “The regulatory body asked us to further purify the protein, so that there are no adverse effects. However, no adverse effects were reported when we carried out the study. Now we are reworking on the composition of the vaccine and we should be ready for another control trial within this year. We will then submit the results to RCGM,” he said.
Herbal remedy against HIV
The National Institute of Immunology is also developing anti-HIV activity microbicides. Microbicides are compounds that can be applied inside the vagina or rectum to prevent sexually transmitted infections.
Dr Gupta revealed that 30 medicinal plants had been screened in collaboration with the National Botanical Research Institute, Lucknow. “We found at least four plants have properties to act as agents to prevent HIV transmission,” he said.
He added that in phase II, active principles in the plant extracts would be detected and formulations made to produce microbicides in the form of gel, tablet, foam, etc.
The Institute has filed for patent for one of the four plants. Currently, about 30 clinical trials are going on in this field.
(Published in Deccan Herald on 15th February, 2011)