COBAS® HIV-1/HIV-2 QUALITATIVE (192T)

Additional Manufacturer Narrative

THE COBAS 8800 SERIAL NUMBER WAS (B)(6). THE INVESTIGATION IS ONGOING.

Description of Event or Problem

THERE WAS AN ALLEGATION OF FALSE NEGATIVE QUESTIONABLE COBAS® HIV-1/HIV-2 QUALITATIVE (192T) RESULTS FOR TWO PATIENTS FROM THE COBAS 8800 ANALYZER COMPARED TO AN ABBOTT ARCHITECT AND BIORAD GEENIUS HIV 1/2 SUPPLEMENTAL ASSAY. PATIENT 1 ON (B)(6) 2023: THE ABBOTT ARCHITECT RESULT WAS 2.51 S/CO. THE SAMPLE WAS RETESTED IN DUPLICATE ON THE ABBOTT ARCHITECT AND THE RESULTS WERE 2.57 S/CO AND 2.69 S/CO. THE SAMPLE WAS TESTED ON BIORAD GEENIUS AND THE RESULT WAS NON-REACTIVE. THE SAMPLE WAS TESTED ON THE COBAS 8800 USING REAGENT LOT J09842 AND THE RESULT WAS NON-REACTIVE. PATIENT 2 ON (B)(6) 2023: THE ABBOTT ARCHITECT RESULT WAS 1.27 S/CO. THE SAMPLE WAS RETESTED IN DUPLICATE ON THE ABBOTT ARCHITECT AND THE RESULTS WERE 1.13 S/CO AND 1.35 S/CO. THE SAMPLE WAS TESTED ON BIORAD GEENIUS AND THE RESULT WAS NON-REACTIVE. THE SAMPLE WAS TESTED ON THE COBAS 8800 USING REAGENT LOT J21457 AND THE RESULT WAS NON-REACTIVE. ON (B)(6) 2024 (NEW SAMPLE) THE ABBOTT ARCHITECT RESULT WAS 0.86 S/CO. THE SAMPLE WAS TESTED ON THE COBAS 8800 USING REAGENT LOT K08915 AND THE RESULT WAS NON-REACTIVE. ON (B)(6) 2024 (NEW SAMPLE) THE ABBOTT ARCHITECT RESULT WAS 0.87 S/CO. THE SAMPLE WAS TESTED ON THE COBAS 8800 USING REAGENT LOT K08915 AND THE RESULT WAS NON-REACTIVE.

Additional Manufacturer Narrative

THE INVESTIGATION DID NOT IDENTIFY A PRODUCT PROBLEM. ALL OF THE ALLEGED RESULTS WERE VALID AND THERE WAS NO INDICATION OF AN ERRONEOUS RESULT. THE EVENT WAS CONSISTENT WITH LOW POSITIVE SAMPLES NEAR THE LEVEL OF DETECTION (LOD). AT THE LOD, IT IS THE EXPECTED BEHAVIOR FOR SAMPLES TO WAIVER FROM POSITIVE TO NEGATIVE. THIS BEHAVIOR WAS ALSO SEEN IN THE RESULTS FROM THE COMPETITOR TESTS FOR THE SAME ALLEGED SAMPLES.