1. K.H. Buchheit, A. Daas, C.M. Nübling, J.M. Spieser 3 July 2003
SoGAT XVI
Collaborative Study for Establishment of a Ph. Eur. BRP for B19 Virus DNA Testing of Plasma Pools by NAT
K.H. Buchheit, A. Daas, C.M. Nübling, J.M. Spieser
3 July 2003

2. Candidate BRP B19 positive plasma (ca 109 IU/ml), from window phase
Liquid bulk material (106 IU/ml)
Diluent: Human plasma negative for HCV, HBV, HIV1 (NAT & serology)
Lyophilisation:
ca 5400 vials, 0.5 ml
residual water: 0.98 ± 0.65%
K.H. Buchheit SoGAT 3/7/03

3. Collaborative study 16 labs (OMCLs, manuf., NAT test labs, kit manuf.)
Calibration vs 1st IS ( IU/vial)
B19 negative plasma as dilution matrix
Qualitative assay (13 labs)
4 independent tests
dilution series proposed
≥ 3 half-log dil. around dilutional end point
Quantitative assay (5 labs)
Measure in parallel, diff. conc., linear range
K.H. Buchheit SoGAT 3/7/03

4. Results (1) (Values as log10 IU/ml)
Qualitative assay (n = 12)
5.64 ± 0.17 (C.L.: %)
Quantitative assay (n = 5)
5.83 ± 0.05 (C.L.: %)
Combined
5.80 ± 0.05 (C.L.: %)
IU/ml
K.H. Buchheit SoGAT 3/7/03

5. Grey cells: qualitative assays Black cells: quantitative assays
Results (2)
Grey cells: qualitative assays Black cells: quantitative assays
K.H. Buchheit SoGAT 3/7/03

6. cBRP suitable for intended purpose
Assigned potency: IU/ml
Dilution for threshold control: 1/101.8 = 1/63
No. positive results/ no. assays for each dilution
K.H. Buchheit SoGAT 3/7/03

7. Next Steps OMCL guideline for B19 NAT validation (M. Nübling)
Validation panel
PTS studies for OMCLs & manufactures (if requested)
K.H. Buchheit SoGAT 3/7/03