ATELLICA IM CA 19-9 (CA 19-9)

Additional Manufacturer Narrative

A CUSTOMER FROM OUTSIDE THE UNITED STATES REPORTED OBSERVATION OF A DEPRESSED ATELLICA IM CA 19 9 (CA 19 9) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING OF THE SAME SAMPLE FOLLOWING DILUTION. NO ISSUES WERE NOTED WITH RESPECT TO ASSAY CALIBRATION OR QUALITY CONTROL (QC) RESULTS. SIEMENS IS INVESTIGATING.

Description of Event or Problem

THE CUSTOMER REPORTS OBSERVATION OF A DEPRESSED ATELLICA IM CA 19 9 (CA 19 9) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING FOLLOWING DILUTION WHEN USING CA 19-9 KIT LOT 541. AN INITIAL RESULT FOR A 74-YEAR-OLD MALE PATIENT WAS CONSIDERED FALSELY DEPRESSED VS. A REPEAT TEST OF THE SAME SAMPLE FOLLOWING 10-FOLD DILUTION. THE SECOND TEST WAS PERFORMED USING THE SAME REAGENT PACK, WITH AN AUTOMATIC 10-FOLD DILUTION OF THE SAMPLE. THE PATIENT, WITH KNOWN CANCER, ALSO DEMONSTRATED INCREASING PARALLEL CURVES FOR AFP MEASUREMENTS. THE HIGHER CA 19-9 RESULT FROM THE DILUTED SAMPLE WAS CONSIDERED CORRECT, AS IT BETTER MATCHED THE PATIENT¿S CLINICAL DATA. THERE ARE NO ALLEGATIONS OF PATIENT HARM, CHANGES IN TREATMENT, OR DELAYS OF DIAGNOSIS IN ASSOCIATION WITH THE OBSERVED DISCORDANCE.

Additional Manufacturer Narrative

A CUSTOMER FROM OUTSIDE THE UNITED STATES REPORTED OBSERVATION OF A DEPRESSED ATELLICA IM CA 19 9 (CA 19 9) RESULT WHICH WAS DISCORDANT RELATIVE TO REPEAT TESTING FOLLOWING DILUTION. MDR 1219913-2024-00464 WAS INITIALLY SUBMITTED ON 11-NOV-2024. UPDATE, 24-JAN-2025: SIEMENS HAS CONCLUDED THE INVESTIGATION. SIEMENS INVESTIGATED CA 19-9 DILUTION-RECOVERY PERFORMANCE ACROSS MULTIPLE REAGENT LOTS, WHICH INCLUDED BOTH MANUAL AND AUTO 1:10 DILUTIONS WITH MEDICAL DECISION POOL (MDP) LEVEL 5, WHICH IS COMMUTABLE TO PATIENT SAMPLES, HIGH CALIBRATOR LOTS C941H, C943H AND C945H AND HIGH DOSE PATIENT SAMPLES. THE OBSERVED PERFORMANCE MET THE ATELLICA IM DESIGN VERIFICATION REQUIREMENTS, WHICH ALLOW A +/- 30% TOLERANCE FOR AUTO-DILUTION RECOVERY. FURTHER INVESTIGATION DEMONSTRATED THAT THE CA 19-9 ASSAY HAS MET ACCURACY SPECIFICATIONS FOR ALL INTERNAL CONTROL MATERIALS TESTED DURING LOT-QUALIFICATION TESTING OF LOTS RELEASED WITHIN THE PAST TWO YEARS. IT IS NOTED THAT DILUTION-RECOVERY PERFORMANCE IS NOT CONSISTENT ACROSS ALL SAMPLES, AND IT IS POSSIBLE THAT SOME PATIENT SAMPLES MAY EXHIBIT DILUTION OVER-RECOVERY WITH MUCIN/MUCIN-LIKE ASSAYS SUCH AS CA 19-9. THE PRODUCT¿S INSTRUCTIONS FOR USE (IFU) STATES ¿SAMPLE-DEPENDENT NONLINEAR DILUTIONS CAN BE OBSERVED.¿ [REFERENCE: WILD D, ED. THE IMMUNOASSAY HANDBOOK. 4TH ED. OXFORD, UK: ELSEVIER SCIENCE; 2013:842] ADDITIONALLY, IT IS IMPORTANT TO NOTE THAT THE ATELLICA IM CA19-9 IFU STATES THAT THE ASSAY IS USEFUL AS AN AID IN MONITORING THE STATUS OF PATIENTS HAVING CONFIRMED PANCREATIC CANCER WHO HAVE LEVELS OF SERUM AT SOME POINT EXCEEDING THE MEDIAN CONCENTRATION. THE ASSAY IS NOT INTENDED FOR SCREENING PURPOSES AND SHOULD ALWAYS BE USED IN CONJUNCTION WITH ALL OTHER CLINICAL AND LABORATORY DATA. THE ASSAY PROVIDES RESULTS FROM 1.20 ¿ 700 U/ML. ONLY SAMPLES WITH LEVELS >700 U/ML SHOULD BE DILUTED BEFORE RE-TESTING. BASED ON THE AVAILABLE INFORMATION, NO PRODUCT PROBLEM WAS IDENTIFIED, AND NO FURTHER INVESTIGATION IS REQUIRED. NOTE: IN SECTION H6, THE CODES FOR INVESTIGATION FINDINGS AND INVESTIGATION CONCLUSIONS HAVE BEEN UPDATED.