title: A multi-dose serological assay suitable to quantify the potency of inactivated rabies vaccines for veterinary use.
abstract: The mouse vaccination-challenge test, which is the most widely used method for determining the potency of inactivated rabies vaccines, is imprecise, time-consuming, and causes severe distress to the test animals. An alternative single-dose serological method has been implemented in the European Pharmacopoeia Monograph 0451 to replace the mouse challenge test for batch release. This single-dose limit method provides semi-quantitative results, but is not suitable for quantifying potency. We have now extended this serological method to a multi-dose format which allows a quantification of vaccine potency. In studies including all rabies vaccine strains relevant for Europe, we found dose-dependency for all vaccines and standard preparations. We have demonstrated that the multi-dose serological approach provides reliable quantitative potency results and is more precise than the mouse vaccination-challenge test. We have shown that adjuvanted vaccines can be calibrated against non-adjuvanted material, and that reference material can be calibrated against the International Standard. The method is therefore capable of assigning potency with the additional advantage of requiring fewer animals and reducing distress. Once the applicability of the method has been further verified in a collaborative study, it can complement the single-dose assay and eventually eliminate the need for the mouse challenge test.
authors.affiliation: Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Paul-Ehrlich-Strasse 51-59, 63225 Langen, Germany. Electronic address: beate.kraemer@pei.de.
authors.forename: Beate
authors.initials: B
authors.lastname: Krämer
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Kamphuis
authors.forename: Kay-Martin
authors.initials: KM
authors.lastname: Hanschmann
authors.forename: Catherine
authors.initials: C
authors.lastname: Milne
authors.forename: Arnold
authors.initials: A
authors.lastname: Daas
authors.forename: Karin
authors.initials: K
authors.lastname: Duchow
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D005260:Female; D051379:Mice; D008815:Mice, Inbred Strains; D011818:Rabies / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D011819:Rabies Vaccines / Q000008:administration & dosage / Q000276:immunology / Q000592:standards*; D011820:Rabies virus / Q000145:classification / Q000276:immunology; D012015:Reference Standards; D015203:Reproducibility of Results; D012698:Serologic Tests / Q000379:methods; D014611:Vaccination / Q000379:methods / Q000662:veterinary*; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology / Q000592:standards*; D014730:Veterinary Medicine / Q000379:methods
chemical_list: D000914:Antibodies, Viral; D011819:Rabies Vaccines; D015164:Vaccines, Inactivated
keywords: 3R alternative; BRP4; Batch potency test; EDQM; European Directorate for the Quality of Medicines & HealthCare; FCS; International WHO Standard for anti-rabies immunoglobulin (human); MDSA; NIH test; PBS; RAI; RFFIT; RVNA; Serological assay; Veterinary rabies vaccine; biological reference preparation batch 4; fetal calf serum; mRFFIT; modified rapid fluorescent focus inhibition test; mouse challenge test developed by the National Institutes of Health; multi-dose serological assay; phosphate buffered saline; rabies virus neutralizing antibodies