HyperRho-D (Rho(D) Immune Globulin-Human) (SD Viral Inactivated) Mechanism of Action

Pharmacology: Bayrho-D (Rho(D) Immune Globulin-Human) (SD Viral Inactivated) full dose is used to prevent isoimmunization in the Rho(D)-negative individual exposed to Rho(D)-positive blood as a result of a fetomaternal hemorrhage occurring during a delivery of a Rho(D)-positive infant, abortion (either spontaneous or induced), or following amniocentesis or abdominal trauma. Similarly, immunization resulting in the production of anti-Rho(D) following transfusion of Rh-positive red cells to a Rho(D)-negative recipient may be prevented by administering Rho(D) immune globulin (human).
Rh hemolytic disease of the newborn is the result of the active immunization of a Rho(D)-negative mother by Rho(D)-positive red cells entering the maternal circulation during a previous delivery, abortion, amniocentesis, abdominal trauma, or as a result of red cell transfusion. Bayrho-D (Rho(D) Immune Globulin-Human) (SD Viral Inactivated) full dose acts by suppressing the immune response of Rho(D)-negative individuals to Rho(D)-positive red blood cells. The mechanism of action of Bayrho-D (Rho(D) Immune Globulin-Human) (SD Viral Inactivated) full dose is not fully understood.
The administration of Rho(D) immune globulin (human) within 72 hrs at a full-term delivery of a Rho(D)-positive infant by a Rho(D)-negative mother reduces the incidence of Rh isoimmunization from 12-18% to 19-29%.
The 1-2% treatment failures are probably due to isoimmunization occurring during the latter part of pregnancy or following delivery. Bowman and Pollock have reported that the incidence of isoimmunization can be further reduced from approximately 1.6% to less than 0.5% by administering Rho(D) immune globulin (human) in 2 doses, one antenatal at 28 weeks of gestation and another following delivery.
In a clinical study in 8 healthy human adults receiving another hyperimmune immune globulin product treated with solvent/detergent, rabies immune globulin (human) (BayRab), prepared by the same manufacturing process, detectable passive 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 suggest that passive immunization with immune globulin products is not affected by the solvent/detergent treatment.