A trial of a new human monoclonal antibody treatment against rabies has been successful, shaping up as a potential alternative to expensive alternatives derived from horse serum or human blood.
The new cost-effective rabies therapy developed by MassBiologics at the University of Massachusetts and the Serum Institute of India has the potential to save tens of thousands of lives each year, its developers say.
The recently completed trial in India showed that the new monoclonal antibody (RAB-1) therapy resulted in protective antibody levels in the serum of treated subjects equal to the current standard of treatment, which is often not available in the areas of the world hit hardest by rabies.
Details of the study were reported at the American Society for Microbiology's 50th annual Interscience Conference on Antimicrobial Agents and Chemotherapy meeting in Boston.
"We are very encouraged by the results from this trial," said Dr Donna Ambrosino, executive director of MassBiologics and a professor of pediatrics at the university's medical school.
The World Health Organisation estimates more than 10 million people are exposed to rabid animals each year, resulting in more than 55,000 deaths. About 95 per cent of human deaths from rabies occur in Asia and Africa.
Untreated, the virus causes acute brain swelling that is fatal once symptoms appear. However, the infection is preventable by prompt treatment after exposure, involving administration of a rabies vaccine and rabies immune globulin (RIG) soon after exposure.
While the vaccine is often available, the preferred human rabies immune globulin (HRIG), which is derived from human blood, is expensive material and typically not available in developing countries.
As an alternative to HRIG, equine immune globulin derived from horse serum is used in many parts of the world, but it is also scarce, expensive and can carry significant side effects.
Too frequently, however, there is neither HRIG nor equine product available to treat all those in the developing world who are bitten by rabid animals.