The animal study results of the first DNA rabies vaccine developed jointly by the Indian Institute of Science (IISc), Bangalore and the Indian Immunologicals, Hyderabad, would be submitted to the Drug Controller General of India (DCGI) soon. The animal trials, which was completed animal trails in December 2002, has been with the Department of Biotechnology (DBT) as the project is sponsored by the same. The vaccine, which has completed the phase 2 studies, would be taken to human trials most likely in a couple months.
Prof. P N Rangarajan, associate professor, Biochemistry Department, IISc, told pharmabiz.com that no technical information on the trial results could be given until the clearance comes from DCGI. The vaccine, which perhaps the world's first combination vaccine containing DNA vaccine and a low dose of cell culture vaccine, is however expected to be put on human trails in a couple of months if the DCGI clearance is through.
Once the vaccine reaches market successfully, it is expected to be much more cheaper than the existing vaccines. Prof. Rangarajan, who has been working on combination rabies vaccine (CRV) for the past five years, informed that DBT is funding the current tests under Jai Vignan Vaccine Mission.
The latest rabies vaccine for animals and humans are cell cultured and expensive to produce and needs to be stored in a refrigerated condition.
Government hospitals in India continue to use the nerve tissue vaccine used for rabies which is been recently banned by the World Health Organisation, said Prof. Rangarajan.
The research in DNA rabies vaccine (DRV) was done by taking a gene from the rabies virus and introducing it into a bacteria that multiplies. This method proved only 50 – 70 percent success although the cost of production was less than that of the cell culture vaccine. Working further on its potency, the IISc team of scientists found that addition of small quantity of the modern cell culture vaccine enhances the potency of DRV and this unique combination vaccine gave 100 per cent result at a lesser price. The principle works best on both human and veterinary vaccine and has shown positive results on mice and cattle.
At present there are three-cell culture rabies vaccine for humans that cost Rs. 200 to Rs. 300 per inoculation. A patient needs to have four to five injections after contraction rabies. People who usually get bitten by and dogs are like rag pickers and urchins who cannot afford the vaccine and this is where CRV comes in as a benefit.
The IISc team has already filed an international patent under the PCT (Patent Cooperative Treaty) and its International Search Report has confirmed it as a unique vaccine, informed Prof. Rangarajan. “We now have to file for patents in all PCT countries and that could take another year.”
Indian Immunologicals set up by the National Diary Development Board which is headed by Dr. V A Srinivasan, has been selected for the production of the vaccine as the company has two culture rabies vaccines including Abhayrab presently in the market.