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.
To address the supply problems and side-effect issues, MassBiologics and the Serum of Institute of India launched an effort to develop a monoclonal antibody (MAB) that could be used in place of HRIG. Pre-clinical testing of RAB-1 showed that it neutralized all isolates available from a panel of rabies viruses. MassBiologics then partnered with the Serum Institute of India, which is one of the world's largest manufacturers of vaccines, including a major supplier of the rabies vaccine, to develop the capacity to produce monoclonal antibodies in India, and advance RAB-1 into clinical trials.
In the Phase 1 trial run at the KEM hospital, 74 healthy volunteers were randomized into several groups that either received escalating doses of RAB-1 or of HRIG combined with vaccine. The RAB-1 was well tolerated by all subjects, with no serious adverse side-effects caused by the MAB. Blood samples were then analyzed and showed the volunteers who received RAB-1 and vaccine at a dose of 0.150 mg/kg had levels of rabies antibodies equal to or higher than the levels from those volunteers who had received the standard does of HRIG and vaccine. The half life of RAB-1 was 18-19 days.
Blood samples were also analyzed by the Kansas State Veterinary Diagnostic Laboratory to determine if antibodies present in the volunteers' bloodstream could neu
|Contact: Michael Cohen|
University of Massachusetts Medical School