H6: investigation: the complaint investigation for false negative result when using the bd max ct/gc/tv (ref.(b)(4)) lot 1340818 was performed by the review of the manufacturing records, customer¿s data analysis and verification of complaints history.Review of the manufacturing records of bd max ct/gc/tv indicated that the lot was manufactured according to specifications and met performance requirements.Customer reported one sample which initially tested negative (run 1019 a4) with strong amplification of the chlamydia trachomatis target but tested positive when repeated from the same sbt in run 1021 b4 with strong amplification and a ct sdpa value earlier than 15.Customer provided these two run files for investigation.Manual pcr curve adjudication of the sample revealed a strong positive result in run 1019 position a4.However, the result reported by the bdmax was negative due to the atypical curve behavior.Indeed, a ct sdpa value for that sample was earlier than the minimum cycle threshold required to be considered a valid amplification resulting in a negative result.Clinical study for the bd max¿ ct/gc/tv assay, performed on more than 2600 subjects, showed that positive clinical samples usually obtain ct sdpa values higher than 15.A true positive patient sample with a ct sdpa value this early is atypical.The ¿bd max ct gc tv 58¿ adf was developed to avoid false positive results that can be generated by early noise signal.It is a unique situation where a strong signal, that looks like a true amplification, resulted in a negative result.No reagent issue is suspected.There is no indication of an increase in complaints for false negative result for the bd max ct/gc/tv lot 1340818.The root cause for the false negative results was not identified.Bd cannot confirm the complaint based on the investigation that was executed since the assay results logic perform as expected.Bd did not initiate a corrective and preventive action (capa).Bd apologizes for the inconvenience that this may have caused.Bd quality will continue to monitor for trends.
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