HyperRab (Rabies Immune Globulin-Human) (SD Viral Inactivated) Mechanism of Action

Pharmacology: The usefulness of prophylactic rabies antibody in preventing rabies in humans when administered immediately after exposure was dramatically demonstrated in a group of persons bitten by a rabid wolf in Iran. Similarly, beneficial results were later reported from the USSR. Studies coordinated by WHO helped determine the optimal conditions under which antirabies serum of equine origin and rabies vaccine can be used in man. These studies showed that serum can interfere to a variable extent with the active immunity induced by the vaccine, but could be minimized by booster doses of vaccine after the end of the usual dosage series.
Preparation of rabies immune globulin of human origin with adequate potency was reported by Cabasso et al. In carefully controlled clinical studies, this globulin was used in conjunction with rabies vaccine of duck embryo origin (DEV). These studies determined that a human globulin dose of 20 iu/kg of rabies antibody, given simultaneously with the first DEV dose, resulted in amply detectable levels of passive rabies antibody 24 hrs after injection in all recipients. The injections produced minimal, if any, interference with the subject's endogenous antibody response to DEV.
More recently, human diploid cell rabies vaccines (HDCV) prepared from tissue culture fluids containing rabies virus have received substantial clinical evaluation in Europe and the United States. In a study in adult volunteers, the administration of rabies immune globulin (human) did not interfere with antibody formation induced by HDCV when given in a dose of 20 iu/kg body weight simultaneously with the 1st dose of vaccine.
In a clinical study in 8 healthy human adults receiving a 20-iu/kg IM dose of HyperRab (Rabies Immune Globulin-Human) (SD Viral Inactivated), detectable passive rabies antibody titers were observed in the serum of all subjects by 24 hrs post-injection and persisted through the 21-day study period. These results are consistent with prior studies with non-solvent/detergent-treated product.