Activated coagulation factor Ⅺ(FⅪa)activity in intravenous immunoglobulin preparations from China: An analysis test / 中国输血杂志

ABSTRACT

【Objective】 To investigate the activity level of coagulation factor Ⅺ(FⅪ) in IVIG products, which would provide support for improving the safety and quality control of IVIG products in China. 【Methods】 A total of 71 batches of IVIG products(half of which were closed to expiry date) from 23 domestic manufacturers (brands) were submitted for inspection and assayed for procoagulant activity including FⅪa, FⅪ and NAPTT activity with a chromogenic assay, coagulation proenzymes levels using one stage clotting assays and non-activated partial thromboplastin time (NAPTT). 【Results】 FⅪa(mIU/mL) 32 lots of IVIGs from 15 manufacturers(brands) possessed activities below 0.1 or the detection limit of the assays, 24 IVIG lots from 12 manufacturers were between 0.1~1(0.39±0.20), the remaining 15 IVIG lots from 6 manufacturers had FⅪa activity greater than 1 up to 47(13.27±15.61). FⅪ(mIU/mL) there were no detectable activities of FⅪ in 58 lots from 21 manufacturers, the other 13 lots from 6 manufacturers had IVIGs between 13~309(69.0±98.1), which included in 15 lots of IVIG whose FⅪa activity were greater than 1mIU/mL. NAPTT(s) The coagulation times for aforementioned 15 IVIG lots were all above 150s in the NAPTT test. The NAPTT ratios varied between 0.67 and 0.94(0.83±0.07), and 7 of 15 IVIGs had NAPTT ratios below or equal to 0.8. 【Conclusion】 There are substantial differences in the FⅪ and FⅪa activities in the IVIG preparations from 23 different manufacturers. Most of them had a lower activities; certain lots from specific manufacturers had relatively higher FⅪa activities. Manufactures should evaluate the manufacturing processes and monitor IVIG preparations for the presence of factor Ⅺ-like activity in case of thrombotic risks.