Comparison of the Abbott RealTime Human Immunodeficiency Virus Type 1 (HIV-1) Assay to the Cobas AmpliPrep/Cobas TaqMan HIV-1 Test: Workflow, Reliability, and Direct Costs

Abstract

The Abbott RealTime human immunodeficiency virus type 1 (HIV-1) assay (ART) and the Cobas AmpliPrep/ Cobas TaqMan HIV-1 test (CTM) are commercially available assays for quantification of HIV-1 RNA in plasma. We evaluated performance characteristics, workflow, throughput, reliability, and direct costs of these assays. Both assays yielded good correlation of quantitative results (r ‫؍‬ 0.95) among clinical specimens, with a mean difference of ؊0.34 log 10 copies/ml. Testing of healthy donor plasma specimens yielded "target not detected" results by ART, with "HIV-1 RNA detected, <40 copies/ml" results for 3.3% (3 of 90 samples) of these specimens by CTM. Both the m2000sp/m2000rt (ART) and docked CAP/CTM96 (CTM) instrument systems were capable of operating with continuous, uninterrupted workflow. When daily maintenance and cleaning were included, ART and CTM run durations (5 h 52 min and 6 h 4 min, respectively) and hands-on times (53 min and 46 min, respectively) were similar for a run batch size of 24. While ART was more flexible in terms of run batch size, CTM required fewer user interventions and consistently produced higher specimen throughput rates at 8, 16, and 24 h. Assay run failure rates were 6.3% (1 of 16 runs) and 4.2% (1 of 24 runs) for ART and CTM, respectively (P ‫؍‬ 1.000), with invalid specimen result rates of 1.0% (5 of 495 specimens) and 2.8% (11 of 399 specimens), respectively (P ‫؍‬ 0.073). Direct reagent and consumable costs for each assay were comparable (difference of <10%). In selecting an assay for implementation, laboratories should consider how various assay and instrument features might impact laboratory operation and patient care.

Comparative Performances of HIV-1 RNA Load Assays at Low Viral Load Levels: Results of an International Collaboration

“…However, both TaqMan assays have higher rates of detectability than the Amplicor and RealTime assays. There are a number of factors that may contribute to assay discordance, including viral blips, sample handling, contamination, or differences in the assay primers used (14,31,(37)(38)(39)(40)(41)(42). Furthermore, the assays themselves have inherently lower precision, reproducibility, and sensitivity at the lower ends of their dynamic ranges, which likely contributes to interassay disagreement at low viral loads.…”

Time-Motion Analysis of Four Automated Systems for the Detection of Chlamydia trachomatis and Neisseria gonorrhoeae by Nucleic Acid Amplification Testing

“…There are few timemotion studies reported in the literature that have evaluated the characteristics of these new platforms, particularly for CT/NG testing. [3][4][5][6][7] Head-to-head evaluations that assess multiple systems using a standardized approach provide critical information to laboratories considering adoption of a new platform. In this study, four automated systems routinely used for the detection of CT/NG were assessed for total run time, hands-on and available walk-away time associated with a run, and ease of instrument set up, operation, and maintenance.…”

Impact of the New Abbott m PLUS Feature on Clinical Laboratory Efficiencies of Abbott RealTi m e Assays for Detection of HIV-1, Hepatitis C Virus, Hepatitis B Virus, Chlamydia trachomatis, and Neisseria gonorrhoeae

“…Daily maintenance of instruments is another area of interest to laboratories attempting to reduce hands-on time in order to improve staff and laboratory efficiency. A workflow study by Sloma et al, which included daily maintenance, concluded that the daily maintenance procedures for the Abbott m2000 system required 8 min to complete, while a substantial portion of the hands-on time required to perform the initial Roche COBAS AmpliPrep/COBAS TaqMan run (30 of 46 min) was spent performing daily maintenance procedures (6). These data are supported by the Abbott and Roche instrument manuals, which state that daily maintenance requires 12 to 16 min and 52 to 65 min, respectively (7)(8)(9).…”

“…The two common platforms for HIV-1, hepatitis C virus (HCV), and hepatitis B virus (HBV) load testing are the Abbott m2000 and Roche COBAS AmpliPrep/COBAS TaqMan systems. Several comparative workflow analyses have been performed for these platforms (4)(5)(6). Those studies highlight platform daily maintenance, sample throughput, laboratory tube flexibility, the number of controls per batch, and the time to results.…”