»Rabies Immune Globulin conforms to the regulations of the FDAconcerning biologics (see Biologics á1041ñ).It is a sterile,nonpyrogenic,slightly opalescent solution consisting of globulins derived from blood plasma or serum that has been tested for the absence of hepatitis Bsurface antigen,derived from selected adult human donors who have been immunized with rabies vaccine and have developed high titers of rabies antibody.It has a potency such that when labeled as 150International Units (IU)per mL,it has a geometric mean lower limit (95%confidence)potency value of not less than 110IUper mL,and proportionate lower limit potency values for other labeled potencies,based on the U.S.Standard Rabies Immune Globulin and using the CVS Virus challenge,by neutralization test in mice or tissue culture.It contains not less than 10g and not more than 18g of protein per 100mL,of which not less than 80percent is monomeric immunoglobulin G,having a sedimentation coefficient in the range of 6.0to 7.5S,with no fragments having a sedimentation coefficient less than 6Sand no aggregates having a sedimentation coefficient greater than 12S.It contains 0.3Mglycine as a stabilizing agent,and it contains a suitable preservative.It has a pHbetween 6.4and 7.2,measured in a solution diluted to contain 1percent of protein with 0.15Msodium chloride.It meets the requirements of the test for heat stability.