China NMPA Product Recall - Phenytoin assay dry slides (immunorate rate method)

Ausendo Medical Devices Trading (China) Co., Ltd., acting as the agent for manufacturer Ortho-Clinical Diagnostics, Inc., initiated a voluntary Class II recall for its Phenytoin Assay Dry Tablets (Immunometry). The National Medical Products Administration (NMPA) published this recall (Index No.: JGXX-2017-10714) on July 27, 2017, following a report submitted on July 3, 2017. The primary issue identified was a negative bias occurring when the assay was used to test citrate plasma samples. This inaccuracy was attributed to the dilution effect of the liquid anticoagulant present in citrate plasma tubes, potentially leading to understated phenytoin content results. Importantly, serum and heparinized plasma samples from the same patients did not exhibit this bias. The product is designed for quantitative determination of phenytoin in serum and plasma, with 11 boxes sold in China out of 21 imported. As a corrective action, customers worldwide have been instructed to immediately cease using citrate plasma samples with the Phenytoin Assay Dry Tablets. However, the product remains suitable for use with heparinized plasma or serum samples. Ortho-Clinical Diagnostics plans to issue a notice after revising the product's instructions for use, explicitly removing citrate plasma from the list of recommended sample types to ensure accurate diagnostic outcomes.