(399 days)
No
The summary describes a standard immunoassay technology (ECLIA) for measuring a specific biomarker (NT-proBNP). There is no mention of AI, ML, image processing, or any other technology typically associated with AI/ML applications in medical devices. The performance studies focus on analytical validation of the immunoassay itself.
No
Explanation: The device is an immunoassay system designed for in vitro quantitative determination of a biomarker (NT-proBNP), used as an aid in diagnosis and risk stratification. It is a diagnostic tool, not a device that provides or applies therapy.
Yes
Explanation: The "Intended Use / Indications for Use" section explicitly states that this assay is used "as an aid in the diagnosis of individuals suspected of having heart failure." This directly indicates its role in diagnosis.
No
The device is an immunoassay kit intended for use on specific hardware analyzers (cobas e immunoassay analyzers). The description details the assay's chemical principles and performance characteristics, which are tied to the physical reagents and the analyzer's operation, not solely software functionality.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The "Intended Use / Indications for Use" section explicitly states "Immunoassay for the in vitro quantitative determination of N terminal pro Brain natriuretic peptide in human serum and plasma." The phrase "in vitro" is a key indicator of an IVD.
- Sample Type: The assay is performed on human serum and plasma, which are biological samples taken from the body but tested outside of it.
- Purpose: The assay is used as an aid in the diagnosis, risk stratification, and assessment of cardiovascular events, all of which are diagnostic purposes.
- Device Description: The description details an "electrochemiluminescence immunoassay 'ECLIA'" which is a laboratory-based test method.
- Performance Studies: The document describes various analytical performance studies (precision, sensitivity, linearity, interference, etc.) which are typical evaluations for IVD devices.
Therefore, based on the provided information, the device clearly fits the definition of an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
Immunoassay for the in vitro quantitative determination of N terminal pro Brain natriuretic peptide in human serum and plasma. This assay is used as an aid in the diagnosis of individuals suspected of having heart failure. The test is further indicated for the risk stratification of patients with acute coronary syndrome and heart failure. The test may also serve as an aid in the assessment of increased risk of cardiovascular events and mortality in patients at risk for heart failure who have stable coronary artery disease.
The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.
Product codes (comma separated list FDA assigned to the subject device)
NBC
Device Description
Elecsys proBNP II (updated assay) is a second-generation assay by Roche Diagnostics for the in vitro quantitative determination of N-terminal pro-Brain natriuretic peptide (NT-proBNP) in human serum and plasma with increased biotin tolerance. The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.
The cobas e family of analyzers employs the electrochemiluminescence immunoassay "ECLIA" technology. The assays are an 18-minute (Elecsys proBNP II) and 9 minute (Elecsys proBNP II STAT) application following a sandwich principle using two monoclonal antibodies which are specifically directed against NT-proBNP.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Prescription Use
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Precision/Reproducibility:
- Repeatability and Intermediate Precision
- Methods: The precision of the Elecsys proBNP II assay was evaluated on the cobas e 411 and proBNP II STAT assay was evaluated on one cobas e 601 analyzer at one internal site with three reagent lots over 21 days. The protocol consisted of testing eight serum samples and two controls in single determinations in four separate aliquots (divided into two runs per day) for 21 operating days (n=84). Repeatability and Intermediate Precision were calculated according to EP05-A3.
- Inter-Instrument Variability (CLSI EP5-A3)
- Methods: This was done using the Elecsys proBNP II (updated assay) on three cobas e 411 analyzers and using the Elecsys proBNP II STAT (updated assay) on three cobas e 601 analyzers according to the precision model described in CLSI EP5-A3 guideline. One reagent lot of the updated assay was measured on 5 days in three laboratory sites. A precision experiment according to the CLSI EP05-A3 setup (5-day model, 25 determinations total per sample pool, reagent lot, and site) was conducted at all 3 laboratories, for each of the assays. The sample panel was identical for both and consisted of 8 native human serum sample pools, and 2 concentration levels made of quality control material (PreciControl Cardiac II Level 1 and 2). The samples were not spiked.
Analytical Sensitivity:
- Limit of Blank (LoB) (CLSI EP17-A2)
- Methods: LoB of the Elecsys proBNP II (updated assay) on the cobas e 411 analyzer and of Elecsys proBNP II STAT (updated assay) on the cobas e 601 was determined according to CLSI EP17-A2. In total 60 determinations of an analyte-free sample were obtained on one instrument over ≥ three days in 6 runs with 10-fold determination per run. Three lots of reagent were used.
- Conclusion: All lots met the predetermined acceptance criterion of ≤ 8 pg/mL.
- Limit of Detection (LoD) (CLSI EP17-A2)
- Methods: LoD of the Elecsys proBNP II (updated assay) on the cobas e 411 analyzer and of Elecsys proBNP II STAT (updated assay) on the cobas e 601 analyzer was determined according to CLSI EP17-A2. Five low-level human serum samples were measured on one instrument over ≥ three days in 6 runs with a two-fold determination per run. In total sixty determinations per reagent lot. The experiment was conducted using three reagent lots.
- Conclusion: All lots met the predetermined acceptance criterion of ≤ 10 pg/mL. The LoD claim in the labeling will be set to ≤ 10 pg/mL.
- Limit of Quantitation (CLSI EP17-A2)
- Methods: The LoQ of the Elecsys proBNP II (updated assay) on the cobas e 411 analyzer and of the Elecsys proBNP II STAT (updated assay) on the cobas e 601 analyzer was determined according to CLSI Guideline EP17-A2. A low level sample set 9 native, unaltered serum samples using the Elecsys proBNP II on the cobas e 411 analyzer and 10 native, unaltered serum samples using the Elecsys proBNP II STAT on the cobas e 601 analyzer of known measurand concentration was tested in 5 replicates (aliquots) on one instrument in singleton per day, over 5 days with 1 run per day. Three lots of reagent were used. A total of n=25 measured values were obtained for each sample.
Linearity/Assay Reportable Range (CLSI EP06-Ed2):
- Methods: One high analyte human, native serum sample above measuring range was diluted with analyte free serum. 11 concentrations were prepared throughout the entire measuring range. Samples were assayed in 3-fold determination within a single run.
Endogenous Interference Studies:
- Method for Bilirubin, Hemoglobin and Lipemia:
- Methods: The effect on quantitation of analyte in the presence of endogenous interfering substances using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601. Three different analyte concentration levels (low about 130 pg/mL, medium about 900 pg/mL, high about 20000 pg/mL) in human native serum samples were tested.
- Results/Conclusion: No interference up to: Conjugated Bilirubin 25.0 mg/dL, Unconjugated Bilirubin 25.0 mg/dL, Hemoglobin 1000 mg/dL, Lipemia 1500 mg/dL.
- Method for Biotin:
- Methods: The effect on quantitation of analyte in the presence of Biotin using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601. Three different analyte concentration levels (low about 125 pg/mL, medium about 800 pg/mL, high about 18000 pg/mL) in human native serum samples were tested.
- Conclusion: No interference was seen up to 5000 ng/mL biotin. All predetermined acceptance criteria were met. The claimed Biotin concentration at which no interference is observed is 3500 ng/mL.
- Method for Rheumatoid Factor:
- Methods: The effect on quantitation of analyte in the presence of Rheumatoid Factors using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601. Three different analyte concentration levels (low about 130 pg/mL, medium about 900 pg/mL, high about 20000 pg/mL) in human native serum samples were tested.
- Conclusion: The claimed Rheumatoid factors concentration is 1500 IU/mL.
- Method for Albumin:
- Methods: The effect on quantitation of analyte in the presence of Albumin using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601. Three different analyte concentration levels (low about 140 pg/mL, medium about 1000 pg/mL, high about 23000 pg/mL) in human native serum samples were tested.
- Conclusion: The claimed Albumin concentration is 7 g/dL.
Cross-Reactivity:
- Methods: Two human native serum samples with low (about 150 pg/mL) and high (about 2500 pg/mL) analyte levels were aliquoted and spiked with potential cross-reactants. One aliquot was left unspiked to serve as a reference. Samples were measured on the cobas e 411 analyzer for Elecsys proBNP II and on the cobas e 601 analyzer for Elecsys proBNP II STAT.
Exogenous Interference - Drugs:
- Methods: Two human native serum samples with approximately 125 pg/mL and 2000 pg/mL were analyzed using the cobas e 411 and cobas e 601 analyzer. These samples were divided into an appropriate number of aliquots. One aliquot of each serum sample was spiked with the respective amount (volume) of the drug (= interference sample) and another aliquot was spiked (if applicable) with the same volume of the solvent of the respective drug (= reference sample). The recovery of the interference sample was calculated as percent recovery compared to the reference sample. In total, 18 common and 33 special pharmaceutic compounds were analyzed and measured.
- Conclusion: No interference was seen with the drugs tested.
Matrix Comparisons:
- Methods: The effect on quantitation of analyte in the presence of anticoagulants with the Elecsys proBNP II (updated assay) was determined on the cobas e 411 and with the Elecsys proBNP II STAT (updated assay) was determined on the cobas e 601 by comparing values obtained from native samples (single donors) drawn into Serum, Li-Heparin and K2-EDTA plasma.
- Sample Matrix Comparison for Elecsys proBNP II:
- Li Heparin: Slope 0.990, Intercept 0.898 pg/mL, Correlation coefficient Pearson's r 0.998, Absolute Bias at 125 pg/mL -0.391, % Bias at 125 pg/mL -0.3.
- K2-EDTA: Slope 1.01, Intercept -0.985 pg/mL, Correlation coefficient Pearson's r 0.999, Absolute Bias at 125 pg/mL -0.189, % Bias at 125 pg/mL -0.2.
- Sample Matrix Comparison for Elecsys proBNP II:
Method comparison:
- Elecsys proBNP II STAT:
- Sample Size: 1928 subjects.
- Comparison: Biotin-remediated Elecsys proBNP II STAT assay (09315276160, y) against Elecsys proBNP II STAT assay (05390109160, x).
- Passing-Bablok Regression Fit: Intercept -1.60, Slope 1.01.
- Correlation: Kendall's tau 0.99, Pearson's r 1.00.
- Predicted Relative Bias (%): -0.8% at 125 pg/mL, -0.0% at 300 pg/mL, 0.2% at 450 pg/mL, 0.3% at 900 pg/mL, 0.4% at 1800 pg/mL.
- Elecsys proBNP II:
- Sample Size: 1940 subjects.
- Comparison: Biotin-remediated Elecsys proBNP II assay (09315268160, y) against Elecsys proBNP II assay (04842464160, x).
- Passing-Bablok Regression Fit: Intercept -2.88, Slope 0.98.
- Correlation: Kendall's tau 0.99, Pearson's r 1.00.
- Predicted Relative Bias (%): -4.2% at 125 pg/mL, -2.8% at 300 pg/mL, -2.5% at 450 pg/mL, -2.2% at 900 pg/mL, -2.0% at 1800 pg/mL.
- Conclusion: Testing demonstrated that the Elecsys proBNP II and Elecsys proBNP II STAT assays are safe and effective and are substantially equivalent to the assays cleared in K072437 and K092649. Biotin tolerance has been improved for patient safety.
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
Not Found
Predicate Device(s)
Reference Device(s)
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information
Not Found
§ 862.1117 B-type natriuretic peptide test system.
(a)
Identification. The B-type natriuretic peptide (BNP) test system is an in vitro diagnostic device intended to measure BNP in whole blood and plasma. Measurements of BNP are used as an aid in the diagnosis of patients with congestive heart failure.(b)
Classification. Class II (special controls). The special control is “Class II Special Control Guidance Document for B-Type Natriuretic Peptide Premarket Notifications; Final Guidance for Industry and FDA Reviewers.”
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Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: a symbol on the left and the FDA name on the right. The symbol on the left is a stylized image of a human figure, while the FDA name on the right is written in blue letters. The words "U.S. FOOD & DRUG ADMINISTRATION" are written in a clear, sans-serif font.
March 31, 2022
Roche Diagnostics Jane Phillips Sr. Regulatory Program Manager 9115 Hague Road Indianapolis, Indiana 46250
Re: K210546
Trade/Device Name: Elecsys proBNP II, Elecsys proBNP II STAT Regulation Number: 21 CFR 862.1117 Regulation Name: B-Type Natriuretic Peptide Test System Regulatory Class: Class II Product Code: NBC Dated: December 8, 2021 Received: December 8, 2021
Dear Jane Phillips:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
1
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely.
Marianela Perez-Torres, Ph.D. Deputy Director Division of Chemistry and Toxicology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
2
Indications for Use
510(k) Number (if known) K210546
Device Name Elecsys proBNP II
Indications for Use (Describe)
Immunoassay for the in vitro quantitative determination of N terminal pro Brain natriuretic peptide in human serum and plasma. This assay is used as an aid in the diagnosis of individuals suspected of having heart failure. The test is further indicated for the risk stratification of patients with acute coronary syndrome and heart failure. The test may also serve as an aid in the assessment of increased risk of cardiovascular events and mortality in patients at risk for heart failure who have stable coronary artery disease.
The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.
| Type of Use (Select one or both, as applicable) | |
|---|---|
| X Prescription Use (Part 21 CFR 801 Subpart D) | Over-The-Counter Use (21 CFR 801 Subpart C) |
CONTINUE ON A SEPARATE PAGE IF NEEDED.
This section applies only to requirements of the Paperwork Reduction Act of 1995.
DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff(@fda.hhs.gov
"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."
3
Indications for Use
510(k) Number (if known) K210546
Device Name Elecsys proBNP II STAT
Indications for Use (Describe)
Immunoassay for the in vitro quantitative determination of Nterminal proBrain natruretic peptide in human serum and plasma. This assay is used as an aid in the diagnosis of individuals suspected of having heart failure. The test is further indicated for the risk stratification of patients with acute coronary syndrome and heart failure. The test may also serve as an aid in the assessment of increased risk of cardiovascular events and mortality in patients at risk for heart failure who have stable coronary artery disease.
The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.
| Type of Use (Select one or both, as applicable) | |
|---|---|
| ☑ Prescription Use (Part 21 CFR 801 Subpart D) | ☐ Over-The-Counter Use (21 CFR 801 Subpart C) |
CONTINUE ON A SEPARATE PAGE IF NEEDED.
This section applies only to requirements of the Paperwork Reduction Act of 1995.
DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff(@fda.hhs.gov
"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."
4
510(k) Summary
March 28th, 2022
U.S. Food and Drug Administration Center for Devices and Radiological Heath Document Mail Center - WO66 Room 0609 10903 New Hampshire Avenue Silver Spring, MD 20993-0002
- Purpose In accordance with 21 CFR 807.87, Roche Diagnostics Corporation hereby submits official notification as required by Section 510(k) of the Federal Food, Drug and Cosmetics Act of our intention to market the device described in this Premarket Notification [510(k)].
510(k) Summary K210546
| Device Name | Proprietary name: | Elecsys proBNP II and Elecsys proBNP II STAT |
|---|---|---|
| Common name: | proBNP II and proBNP II STAT |
5
| Owner | Roche Diagnostics
9115 Hague Road
Indianapolis, IN 46250
Phone: 317-521-2000
Fax: 317-521-1413 |
|---------|------------------------------------------------------------------------------------------------------------|
| Contact | Jane Phillips, PhD |
| Date | March 28th, 2022 |
| Panel | Product
Code | Classification Name | Regulation
n Citation |
|--------------------|-----------------|-------------------------------------------|--------------------------|
| Clinical Chemistry | NBC | B-Type Natriuretic
Peptide Test System | 862.1117 |
6
Substantial The Elecsys proBNP II (updated assay) is substantially Equivalence equivalent to the Elecsys proBNP II (old assay, K072437) The Elecsys proBNP II (updated assay) STAT is substantially equivalent to the Elecsys proBNP II STAT (old assav, K092649) Intended
Use
Elecsys proBNP II STAT
Immunoassay for the in vitro quantitative determination of N-terminal proBrain natriuretic peptide in human serum and plasma. This assay is used as an aid in the diagnosis of individuals suspected of having heart failure. The test is further indicated for the risk stratification of patients with acute coronary syndrome and heart failure. The test may also serve as an aid in the assessment of increased risk of cardiovascular events and mortality in patients at risk for heart failure who have stable coronary artery disease. The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.
Elecsvs proBNP II
Immunoassay for the in vitro quantitative determination of N-terminal pro-Brain natriuretic peptide in human serum and plasma. This assay is used as an aid in the diagnosis of individuals suspected of having heart failure. The test is further indicated for the risk stratification of patients with acute coronary syndrome and heart failure. The test may also serve as an aid in the assessment of increased risk of cardiovascular events and mortality in patients at risk for heart failure who have stable coronary artery disease. The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.
7
| ltem | Elecsys proBNP II
(old assay design) | Elecsys proBNP II
(updated assay design) | Change description |
|------------------|------------------------------------------------------|------------------------------------------------------|----------------------------------------------------|
| Proprietary name | Elecsys proBNP II | Elecsys proBNP II | None |
| Technology | ECLIA | ECLIA | None |
| Test format | Sandwich | Sandwich | None |
| Test type | Quantitative | Quantitative | None |
| Assay protocol | R1 + R2 + sample, incubation, +
beads, incubation | R1 + R2 + sample, incubation, +
beads, incubation | None |
| Measuring Range | 5-35000 pg/ml | 36-35000 pg/ml | Changing the lower
end of MR from LoD to
LoQ |
| Biotin Tolerance | Up to 30 ng/mL | Up to 3500 ng/mL | Increase of biotin
tolerance |
Table 1: Similarities and Differences between the Elecsys proBNP II assays
Table 2: Similarities and Differences between the Elecsys proBNP STAT assays
| Item | Elecsys proBNP II
(old assay design) | Elecsys proBNP II
(updated assay design) | Change description |
|------------------|-----------------------------------------|---------------------------------------------|----------------------------------------------------|
| Proprietary name | Elecsys proBNP II STAT | Elecsys proBNP II STAT | None |
| Technology | ECLIA | ECLIA | None |
| Test format | Sandwich | Sandwich | None |
| Test type | Quantitative | Quantitative | None |
| Assay protocol | R1 + R2 + sample+ beads,
incubation | R1 + R2 + sample+ beads,
incubation | None |
| Measuring Range | 5-35000 pg/ml | 36-35000 pg/ml | Changing the lower
end of MR from LoD to
LoQ |
| Biotin Tolerance | Up to 30 ng/mL | Up to 3500 ng/mL | Increase of biotin
tolerance |
Device Description
Elecsys proBNP II (updated assay) is a second-generation assay by Roche Diagnostics for the in vitro quantitative determination of N-terminal pro-Brain natriuretic peptide (NT-proBNP) in human serum and plasma with increased biotin tolerance. The electrochemiluminescence immunoassay "ECLIA" is intended for use on cobas e immunoassay analyzers.
8
The cobas e family of analyzers employs the electrochemiluminescence immunoassay "ECLIA" technology. The assays are an 18-minute (Elecsys proBNP II) and 9 minute (Elecsys proBNP II STAT) application following a sandwich principle using two monoclonal antibodies which are specifically directed against NT-proBNP.
Changes to Reagent Composition
For the neutralization of free biotin in serum and plasma, Roche developed an antibody, which binds to free biotin. The antibodies are specific for free biotin and do not bind to or interact with the biotin-linker conjugates.
Analytical Performance
Precision/Reproducibility
Repeatability and Intermediate Precision
Precision measurements were conducted to evaluate repeatability (within-run precision) and the intermediate precision (within-laboratory precision) according to the CLSI guideline EP5-A3.
Methods:
The precision of the Elecsys proBNP II assay was evaluated on the cobas e 411 and proBNP II STAT assay was evaluated on one cobas e 601 analyzer at one internal site with three reagent lots over 21 days.
The protocol consisted of testing the eight serum samples and two controls in single determinations in four separate aliquots (divided into two runs per day) for 21 operating days (n=84). Repeatability and Intermediate Precision were calculated according to EP05-A3.
Results:
| cobas e 411 analyzer | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Repeatability | Intermediate precision | ||||||||
| Sample | |||||||||
| (Serum) | Mean | ||||||||
| pg/mL | SD | ||||||||
| pg/mL | SD 95% | ||||||||
| UCL | |||||||||
| pg/mL | CV | ||||||||
| % | CV 95% | ||||||||
| UCL | |||||||||
| % | SD | ||||||||
| pg/mL | SD | ||||||||
| 95% | |||||||||
| UCL | |||||||||
| pg/mL | CV | ||||||||
| % | CV 95% | ||||||||
| UCL | |||||||||
| % | |||||||||
| Human serum 1 | 55.9 | 2.62 | 3.20 | 4.7 | 5.7 | 4.35 | 5.35 | 7.8 | 9.6 |
| Human serum 2 | 129 | 3.07 | 3.76 | 2.4 | 2.9 | 7.40 | 9.61 | 5.7 | 7.5 |
| Human serum 3 | 423 | 8.91 | 10.9 | 2.1 | 2.6 | 18.0 | 22.3 | 4.3 | 5.3 |
| Human serum 4 | 925 | 23.0 | 28.1 | 2.5 | 3.0 | 44.3 | 55.6 | 4.8 | 6.0 |
Lot 391671: Elecsys proBNP II
9
| cobas e 411 analyzer | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Repeatability | Intermediate precision | ||||||||
| Sample | |||||||||
| (Serum) | Mean | ||||||||
| pg/mL | SD | ||||||||
| pg/mL | SD 95% | ||||||||
| UCL | |||||||||
| pg/mL | CV | ||||||||
| % | CV 95% | ||||||||
| UCL | |||||||||
| % | SD | ||||||||
| pg/mL | SD | ||||||||
| 95% | |||||||||
| UCL | |||||||||
| pg/mL | CV | ||||||||
| % | CV 95% | ||||||||
| UCL | |||||||||
| % | |||||||||
| Human serum 5 | 1924 | 43.8 | 53.5 | 2.3 | 2.8 | 88.8 | 110 | 4.6 | 5.7 |
| Human serum 6 | 15620 | 248 | 303 | 1.6 | 1.9 | 662 | 844 | 4.2 | 5.4 |
| Human serum 7 | 33526 | 778 | 950 | 2.3 | 2.8 | 1591 | 2010 | 4.7 | 6.0 |
| Human serum 8 | 337 | 5.11 | 6.24 | 1.5 | 1.8 | 11.4 | 14.4 | 3.4 | 4.3 |
| PreciControl | |||||||||
| Cardiac II 1 | 132 | 3.29 | 4.02 | 2.5 | 3.1 | 5.97 | 7.38 | 4.5 | 5.6 |
| PreciControl | |||||||||
| Cardiac II 2 | 4477 | 135 | 165 | 3.0 | 3.7 | 216 | 267 | 4.8 | 6.0 |
Lot 391674: Elecsys proBNP II STAT
| cobas e 601 analyzer | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Repeatability | Intermediate precision | ||||||||
| Sample | |||||||||
| (Serum) | Mean | ||||||||
| pg/mL | SD | ||||||||
| pg/mL | SD 95% | ||||||||
| UCL | CV | ||||||||
| % | CV 95% | ||||||||
| UCL | SD | ||||||||
| pg/mL | SD | ||||||||
| 95% | |||||||||
| UCL | CV | ||||||||
| % | CV 95% | ||||||||
| UCL | |||||||||
| Human serum 1 | 63.9 | 2.42 | 2.96 | 3.8 | 4.6 | 4.39 | 5.25 | 6.9 | 8.2 |
| Human serum 2 | 144 | 3.36 | 4.10 | 2.3 | 2.8 | 5.87 | 7.08 | 4.1 | 4.9 |
| Human serum 3 | 482 | 12.7 | 15.5 | 2.6 | 3.2 | 18.5 | 22.4 | 3.8 | 4.6 |
| Human serum 4 | 1060 | 24.6 | 30.1 | 2.3 | 2.8 | 34.4 | 40.9 | 3.2 | 3.9 |
| Human serum 5 | 2219 | 51.4 | 62.8 | 2.3 | 2.8 | 77.2 | 94.1 | 3.5 | 4.2 |
| Human serum 6 | 18371 | 405 | 494 | 2.2 | 2.7 | 654 | 801 | 3.6 | 4.4 |
| Human serum 7 | 33967 | 912 | 1114 | 2.7 | 3.3 | 1338 | 1608 | 3.9 | 4.7 |
| Human serum 8 | 331 | 5.01 | 6.12 | 1.5 | 1.8 | 12.7 | 16.1 | 3.8 | 4.9 |
| PreciControl | |||||||||
| Cardiac II 1 | 155 | 4.06 | 4.97 | 2.6 | 3.2 | 6.08 | 7.27 | 3.9 | 4.7 |
| PreciControl | |||||||||
| Cardiac II 2 | 5660 | 116 | 142 | 2.1 | 2.5 | 194 | 237 | 3.4 | 4.2 |
10
Inter-Instrument Variability (CLSI EP5-A3)
Methods (Inter-Instrument):
This was done using the Elecsys proBNP II (updated assay) on three cobas e 411 analyzers and using the Elecsys proBNP II STAT (updated assay) on three cobas e 601 analyzers according to the precision model described in CLSI EP5-A3 guideline. One reagent lot of the updated assay was measured on 5 days in three laboratory sites.
A precision experiment according to the CLSI EP05-A3 setup (5-day model, 25 determinations total per sample pool, reagent lot, and site) was conducted at all 3 laboratories, for each of the assays. The sample panel was identical for both and consisted of 8 native human serum sample pools, and 2 concentration levels made of quality control material (PreciControl Cardiac II Level 1 and 2). The samples were not spiked.
Results:
| Sample | N | Mean | SD | SD UCL | CV[%] | CV[%]
UCL |
|--------|----|--------|------|--------|-------|--------------|
| HS 1 | 75 | 55.2 | 1.02 | 2.06 | 1.8 | 3.7 |
| HS 2 | 75 | 131 | 3.46 | 5.84 | 2.6 | 4.5 |
| HS 3 | 75 | 332 | 5.50 | 10.3 | 1.7 | 3.1 |
| HS 4 | 75 | 471 | 10.3 | 18.0 | 2.2 | 3.8 |
| HS 5 | 75 | 963 | 13.2 | 27.1 | 1.4 | 2.8 |
| HS 6 | 75 | 1773 | 20.0 | 41.1 | 1.1 | 2.3 |
| HS 7 | 75 | 18,719 | 0.00 | N/A | 0.00 | N/A |
| HS 8 | 75 | 31,425 | 0.00 | N/A | 0.00 | N/A |
| PC 1 | 75 | 144 | 1.89 | 3.79 | 1.3 | 2.6 |
| PC 2 | 75 | 4799 | 0.00 | N/A | 0.00 | N/A |
Inter-Instrument Precision, proBNP II on the e411. Units = pg/mL
11
| Sample | N | Mean | SD | SD UCL | CV[%] | CV[%] UCL |
|---|---|---|---|---|---|---|
| HS 1 | 75 | 52.1 | 3.91 | 6.45 | 7.5 | 12.4 |
| HS 2 | 75 | 128 | 9.22 | 15.2 | 7.2 | 11.8 |
| HS 3 | 75 | 317 | 23.8 | 38.9 | 7.5 | 12.3 |
| HS 4 | 75 | 465 | 34.6 | 56.5 | 7.4 | 12.1 |
| HS 5 | 75 | 961 | 74.3 | 122.7 | 7.7 | 12.7 |
| HS 6 | 75 | 1845 | 134 | 220 | 7.3 | 11.9 |
| HS 7 | 75 | 18,477 | 1466 | 2396 | 7.9 | 13.0 |
| HS 8 | 75 | 30,089 | 2394 | 3914 | 8.0 | 13.0 |
| PC 1 | 75 | 145 | 10.9 | 17.9 | 7.5 | 12.3 |
| PC 2 | 75 | 5328 | 399 | 652 | 7.5 | 12.2 |
Inter-Instrument Precision, proBNP II STAT on the e601. Units = pg/mL
12
Analytical Sensitivity
The analytical studies to establish the limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ) were conducted according to the experimental design described in CLSI EP-17-A2
Limit of Blank (LoB) (CLSI EP17-A2)
LoB of the Elecsys proBNP II (updated assay) on the cobas e 411 analyzer and of Elecsys proBNP II STAT (updated assay) on the cobas e 601 was determined according to CLSI EP17-A2. Limit of Blank determines the highest observed measurement values for samples free of analyte. The Limit of Blank was determined as the 95th percentile of measurements of blank samples.
Methods:
In total 60 determinations of an analyte-free sample were obtained on one instrument over ≥ three days in 6 runs with 10-fold determination per run. Three lots of reagent were used in the experimental design.
As the analyzer does not report negative sample concentrations, the data set was truncated and the data were evaluated as the linear interpolation of the 57th ranked observation.
Conclusion:
All lots met the predetermined acceptance criterion of ≤ 8 pg/mL.
Limit of Detection (LoD) (CLSI EP17-A2)
LoD of the Elecsys proBNP II (updated assay) on the cobas e 411 analyzer and of Elecsys proBNP II STAT (updated assay) on the cobas e 601 analyzer was determined according to CLSI EP17-A2. The LoD determines the lower limit for samples with analyte. The LoD was determined as the lowest amount of analyte in a sample that can be detected with a 95% probability.
Methods:
Five low-level human serum samples were measured on one instrument over ≥ three days in 6 runs with a two-fold determination per run. In total sixty determinations per reagent lot. The experiment was conducted using three reagent lots.
13
A pooled estimate of the precision (SD total) for the 5 low level samples was calculated.
LoD was calculated according to EP17-A2, chapter 5.3.3.2 as:
LoD = LoB + 1.653 x SD total (of low analyte samples)
Conclusion:
All lots met the predetermined acceptance criterion of ≤ 10 pg/mL. The LoD claim in the labeling will be set to ≤ 10 pg/mL.
Limit of Quantitation (CLSI EP17-A2)
The LoQ of the Elecsys proBNP II (updated assay) on the cobas e 411 analyzer and of the Elecsys proBNP II STAT (updated assay) on the cobas e 601 analyzer was determined according to CLSI Guideline EP17-A2.
The LoQ was determined as the lowest concentration of analyte which can be reproducibly measured with an intermediate precision of 20% CV.
Methods:
A low level sample set 9 native, unaltered serum samples using the Elecsys proBNP II on the cobas e 411 analyzer and 10 native, unaltered serum samples using the Elecsys proBNP II STAT on the cobas e 601 analyzer of known measurand concentration was tested in 5 replicates (aliquots) on one instrument in singleton per day, over 5 days with 1 run per day. Three lots of reagent were used in the LoQ experiment. A total of n=25 measured values were obtained for each sample. The mean value and the intermediate precision as coefficient of variation (CV) and standard deviation (SD) were calculated for each LoQ sample.
LoQ is defined as the mean value of that sample which is the first that fulfills the specification for the intermediate precision and for which no sample with higher concentration exists that exceeds this specification.
Data are summarized in the following tables, below.
| Reagent Lot | LoQ [pg/mL] |
|---|---|
| 1 391671 | 33.7 |
| 2 391672 | 32.7 |
| 3 391673 | 35.7 |
LoQ Results for Elecsys proBNP II
14
LoQ Results for proBNP II STAT
| Reagent Lot | LoQ [pg/mL] | |
|---|---|---|
| 1 | 391674 | 8.98 |
| 2 | 391675 | 13.6 |
| 3 | 391676 | 7.28 |
Linearity/Assav Reportable Range (CLSI EP06-Ed2)
The linearity study was conducted to demonstrate that measurements across the claimed measuring range for each parameter are linear. The study was performed according to CLSI guideline EP06-Ed2.
Methods:
One high analyte human, native serum sample above measuring rage was diluted with analyte free serum. 11 concentrations were prepared throughout the entire measuring range. Samples were assayed in 3-fold determination within a single run. The linearity data were analyzed as described below.
For each sample and its dilution levels a weighted least square regression by pooled variance is performed.
As one high analyte human, native serum sample above measuring range was diluted with analyte free serum (CLSI Design A1), a regression without intercept is chosen.
As variance increases with concentration, weighted linear regression is used.
As only 3 replicates are available at each dilution step, the weights are computed based on the pooled variance including also the replicates of the next higher as well as the next lower dilution step.
The result table is composed for each experiment, i.e. for the proBNP II (18min) on e411 and the proBNP II STAT on e601. The resulting linearity statistics and deviation results are given in the tables below (rounded data).
15
| Level | Rel Conc | Mean Conc | Expected
Conc. | Predicted Conc. | Deviation | Deviation (%) |
|-------|----------|-----------|-------------------|-----------------|-----------|---------------|
| 1 | 0 | 8.417 | 9.911 | 8.424 | -0.007 | -0.084 |
| 2 | 0.001 | 22.792 | 25.371 | 21.567 | 1.225 | 5.681 |
| 3 | 0.002 | 55.455 | 63.428 | 53.916 | 1.538 | 2.853 |
| 4 | 0.004 | 132.273 | 158.569 | 134.791 | -2.518 | -1.868 |
| 5 | 0.01 | 310.973 | 396.423 | 336.977 | -26.004 | -7.717 |
| 6 | 0.026 | 780.863 | 1014.843 | 862.660 | -81.798 | -9.482 |
| 7 | 0.064 | 1939.433 | 2537.108 | 2156.651 | -217.217 | -10.072 |
| 8 | 0.16 | 4823.735 | 6342.77 | 5391.626 | -567.891 | -10.533 |
| 9 | 0.4 | 13053.629 | 15856.925 | 13479.066 | -425.437 | -3.156 |
| 10 | 0.7 | 24009.672 | 27749.618 | 23588.365 | 421.307 | 1.786 |
| 11 | 1 | 39642.311 | 39642.311 | 33697.665 | 5944.647 | 17.641 |
Linearity for Elecsys proBNP II
Linearity for Elecsys proBNP II STAT
| Level | Rel Conc | Mean Conc | Expected
Conc. | Predicted Conc. | Deviation | Deviation (%) |
|-------|----------|-----------|-------------------|-----------------|-----------|---------------|
| 1 | 0 | 8.515 | 10.024 | 9.720 | -1.206 | -12.403 |
| 2 | 0.001 | 22.355 | 25.662 | 24.884 | -2.529 | -10.164 |
| 3 | 0.002 | 55.493 | 64.156 | 62.210 | -6.717 | -10.797 |
| 4 | 0.004 | 137.301 | 160.39 | 155.524 | -18.224 | -11.717 |
| 5 | 0.01 | 328.36 | 400.975 | 388.810 | -60.450 | -15.547 |
| 6 | 0.026 | 828.107 | 1026.495 | 995.354 | -167.248 | -16.803 |
| 7 | 0.064 | 2066.792 | 2566.238 | 2488.386 | -421.593 | -16.942 |
| 8 | 0.16 | 5351.93 | 6415.594 | 6220.964 | -869.034 | -13.969 |
| 9 | 0.4 | 14054.029 | 16038.985 | 15552.410 | -1498.381 | -9.634 |
| 10 | 0.7 | 25238.171 | 28068.223 | 27216.718 | -1978.547 | -7.270 |
| 11 | 1 | 40097.462 | 40097.462 | 38881.026 | 1216.436 | 3.129 |
16
Endogenous Interference Studies
The purpose of these studies was to evaluate endogenous substances for potential interference with the parameters measured on the cobas e 411 for Elecsys proBNP II (updated assay) and on the cobas e 601 for Elecsys proBNP II STAT (updated assay).
Method for Bilirubin, Hemoglobin and Lipemia:
The effect on quantitation of analyte in the presence of endogenous interfering substances using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601.
Endogenous interferences were determined by testing three different analyte concentration levels (low about 130 pg/mL, medium about 900 pg/mL, high about 20000 pg/mL) in human native serum samples. The high concentrations were spiked with recombinant human proBNP for the bilirubin and lipemia testing.
One aliquot of each serum sample was spiked with the interfering substance (= interference pool) and another aliquot was spiked (if applicable) with the same volume of the solvent of the interfering substance (= dilution pool). The interfering pool was then dilution pool in 10 % increments. The recovery for each sample was calculated by comparison to the reference (unspiked sample).
| Interfering substance | No interference up to |
|---|---|
| Conjugated Bilirubin | 25.0 mg/dL |
| Unconjugated Bilirubin | 25.0 mg/dL |
| Hemoglobin | 1000 mg/dL |
| Lipemia | 1500 mg/dL |
Results/Conclusion for both proBNP II and proBNP II STAT:
Method for Biotin:
The effect on quantitation of analyte in the presence of Biotin using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601.
Biotin interferences were determined by testing three different analyte concentration levels (low about 125 pg/mL, medium about 800 pg/mL, high about 18000 pg/mL) in human native serum samples.
One aliquot of each serum sample was spiked with 15000 ng/mL Biotin (= interference pool) and another aliquot was spiked (if applicable) with the same volume of the solvent of the interfering substance (= dilution pool). The interfering pool was then diluted into the dilution
17
pool in 11 steps. The recovery for each sample was calculated by comparison to the reference (unspiked sample).
Results:
| Volume (Relation) | | Measured
concentration
of analyte
pg/mL | Expected
concentration
of analyte
pg/mL | Concentration
of interferent
ng/mL | Recovery
% |
|-------------------|-----------|--------------------------------------------------|--------------------------------------------------|------------------------------------------|---------------|
| Sample 1a | Sample 1b | | | | |
| 100 | 0.0000 | 123 | 123 | 0.0000 | 100 |
| 96.7 | 3.33 | 124 | 123 | 500 | 101 |
| 93.3 | 6.67 | 127 | 123 | 1000 | 103 |
| 90.0 | 10.0 | 126 | 123 | 1500 | 102 |
| 86.7 | 13.3 | 126 | 123 | 2000 | 102 |
| 83.3 | 16.7 | 127 | 123 | 2500 | 103 |
| 80.0 | 20.0 | 127 | 123 | 3000 | 103 |
| 76.0 | 24.0 | 125 | 123 | 3600 | 102 |
| 66.7 | 33.3 | 116 | 123 | 5000 | 93.9 |
| 33.3 | 66.7 | 85.1 | 123 | 10000 | 69.1 |
| 0.0000 | 100 | 46.9 | 123 | 15000 | 38.1 |
Biotin: Elecsys proBNP II
Conclusion:
No interference was seen up to 5000 ng/mL biotin. All predetermined acceptance criteria were met. The claimed Biotin concentration at which no interference is observed is 3500 ng/mL.
Method for Rheumatoid Factor:
The effect on quantitation of analyte in the presence of Rheumatoid Factors using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601.
Rheumatoid Factors interferences were determined by testing three different analyte concentration levels (low about 130 pg/mL, medium about 900 pg/mL, high about 20000 pg/mL) in human native serum samples. The high sample was spiked with recombinant human NTproBNP.
One aliquot of each serum sample was spiked with 1500 IU/mL Rheumatoid Factors
(= interference pool) and another aliquot was spiked (if applicable) with the same volume of the solvent of the interfering substance (= dilution pool). The interfering pool was then diluted into the dilution pool in 10 % increments. The recovery for each sample was calculated by comparison to the reference (unspiked sample).
18
The claimed Rheumatoid factors concentration is 1500 IU/mL.
Method for Albumin:
The effect on quantitation of analyte in the presence of Albumin using the Elecsys proBNP II was determined on the cobas e 411 and the Elecsys proBNP II STAT was determined on the cobas e 601.
Albumin interferences were determined by testing three different analyte concentration levels (low about 140 pg/mL, medium about 1000 pg/mL, high about 23000 pg/mL) in human native serum samples. The high sample was spiked with human recombinant proBNP.
One aliquot of each serum sample was spiked with 7 g/dL Albumin (= interference pool) and another aliquot was spiked (if applicable) with the same volume of the solvent of the interfering substance (= dilution pool). The interfering pool was then dilution pool in 10 % increments. The recovery for each sample was calculated by comparison to the reference (unspiked sample).
The claimed Albumin concentration is 7 g/dL.
19
Cross-Reactivity
This study was conducted to evaluate the Elecsys proBNP II and proBNP II STAT assay on the cobas e 411 and 601, respectively, for potential cross-reactivity.
Methods
To determine the analytical specificity of the Elecsys proBNP II (updated assay) and Elecsys proBNP II STAT (updated assay), two human native serum samples with low (about 150 pg/mL) and high (about 2500 pg/mL) analyte levels were aliquoted and spiked with potential crossreactants. One aliquot was left unspiked to serve as a reference. Samples were measured on the cobas e 411 analyzer for Elecsys proBNP II and on the cobas e 601 analyzer for Elecsys proBNP II STAT and cross reactivity was calculated according to the formula:
x percent cross reaction =
100 x simulated analyte conc. conc. of cross-reactant spiked
| | Concentration
reactant | Low analyte level | | | High analyte level | | |
|---------------------|---------------------------|------------------------------------------------------------------------------|---------------------------------------------------------------------------|----------------------------------------|------------------------------------------------------------------------------|---------------------------------------------------------------------------|----------------------------------------|
| Cross-reactant | | Measured
analyte
concentration
without Cross
reactant
[pg/mL] | Measured
Analyte
concentration
with Cross
reactant
[pg/mL] | Recovery
with x-
reactant
[%] | Measured
analyte
concentration
without Cross
reactant
[pg/mL] | Measured
Analyte
concentration
with Cross
reactant
[pg/mL] | Recovery
with x-
reactant
[%] |
| Adrenomedullin | 1.0 ng/mL | 143 | 130 | 91 | 2655 | 2573 | 97 |
| Angiotensin I | 0.6 ng/mL | 145 | 144 | 99 | 2640 | 2615 | 99 |
| Angiotensin II | 0.6 ng/mL | 147 | 147 | 100 | 2657 | 2603 | 98 |
| Angiotensin III | 1.0 ng/mL | 147 | 147 | 100 | 2692 | 2617 | 97 |
| Arg-
Vasopressin | 1.0 ng/mL | 139 | 139 | 100 | 2659 | 2647 | 100 |
| Endothelin | 20 pg/mL | 148 | 148 | 100 | 2680 | 2593 | 97 |
| Aldosterone | 0.6 ng/mL | 151 | 146 | 97 | 2655 | 2541 | 96 |
| Renin | 50 ng/mL | 144 | 136 | 94 | 2671 | 2498 | 94 |
| BNP32 | 3.5 µg/mL | 140 | 140 | 100 | 2655 | 2646 | 100 |
| CNP22 | 2.2 µg/mL | 143 | 130 | 91 | 2579 | 2467 | 96 |
| Urodilatin | 3.5 µg/mL | 141 | 142 | 100 | 2682 | 2668 | 99 |
| ANP 1-28 | 3.1 µg/mL | 141 | 142 | 101 | 2668 | 2642 | 99 |
20
| | Concentration
reactant | Low analyte level | | | High analyte level | | |
|------------------------------------------------|---------------------------|------------------------------------------------------------------------------|---------------------------------------------------------------------------|----------------------------------------|------------------------------------------------------------------------------|---------------------------------------------------------------------------|----------------------------------------|
| Cross-reactant | | Measured
analyte
concentration
without Cross
reactant
[pg/mL] | Measured
Analyte
concentration
with Cross
reactant
[pg/mL] | Recovery
with x-
reactant
[%] | Measured
analyte
concentration
without Cross
reactant
[pg/mL] | Measured
Analyte
concentration
with Cross
reactant
[pg/mL] | Recovery
with x-
reactant
[%] |
| NT-proANP
(1-30)
[preproANP (26-
55)] | 3.5 µg/mL | 146 | 144 | 99 | 2677 | 2568 | 96 |
| NT-proANP (31-
67) [preproANP
56-92] | 1.0 ng/mL | 146 | 141 | 97 | 2694 | 2622 | 97 |
| NT-proANP (79-
98) [preproANP
104-123] | 1.0 ng/mL | 146 | 146 | 100 | 3077 | 3181 | 103 |
Exogenous Interference - Drugs
The purpose of this study was to evaluate drugs for potential interference with the parameters measured on the cobas e 411 analyzer for Elecsys proBNP II (updated assay) and on the cobas e 601 analyzer for Elecsys proBNP II STAT (updated assay).
Methods:
Two human native serum samples with approximately 125 pg/mL and 2000 pg/mL were analyzed using the cobas e 411 and cobas e 601 analyzer. These samples were divided into an appropriate number of aliquots. One aliquot of each serum sample was spiked with the respective amount (volume) of the drug (= interference sample) and another aliquot was spiked (if applicable) with the same volume of the solvent of the respective drug (= reference sample). The recovery of the interference sample was calculated as percent recovery compared to the reference sample.
In total. 18 common and 33 special pharmaceutic compounds were analyzed and measured.
Potentially Interfering Drugs and Test Concentrations
| Common therapeutic drugs | Drug concentration
[mg/L] |
|--------------------------|------------------------------|
| Acetylcystein | 150 |
| Ampicillin-Na | 1000 |
| Ascorbic acid | 300 |
| Cefoxitin | 2500 |
21
| Common therapeutic drugs | Drug concentration |
|---|---|
| [mg/L] | |
| Heparin | 5000 IU/L |
| Levodopa | 20 |
| Methyldopa | 20 |
| Metronidazole | 200 |
| Doxycycline | 50 |
| Acetylsalicylic Acid | 1000 |
| Rifampicin | 60 |
| Cyclosporine | 5 |
| Phenylbutazone | 400 |
| Acetaminophen | 200 |
| Ibuprofen | 500 |
| Theophylline | 100 |
| Intralipid | 10000 |
| Ca-Dobesilate | 200 |
| Special therapeutic drugs | Drug concentration
[mg/L] |
|---------------------------|------------------------------|
| Carvedilol | 150 |
| Clopidogrel | 75 |
| Digoxin | 0.5 |
| Epinephrine | 0.37 |
| Insulin | 0.84 |
| Lidocaine | 100 |
| Lisinopril | 40 |
| Methylprednisolone | 80 |
| Metoprolol | 15 |
| Nifedipine | 60 |
| Marcumar | 6 |
| Propafenone | 900 |
| Reteplase | 1.12 |
| Simvastin | 40 |
| Spirolactone | 400 |
| Tolbutamide | 3000 |
| Torasemide | 200 |
22
| Special therapeutic drugs | Drug concentration
[mg/L] |
|------------------------------|------------------------------|
| Verapamil | 120 |
| Propanolol | 0.32 |
| Enalapril | 40 |
| Captopril | 50 |
| Gentamycin | 500 |
| Lovostatin | 80 |
| Pravastatin | 40 |
| Bisoprolol | 10 |
| Glycerol nitrate | 192 |
| Molsidormin | 24 |
| Nicardipin | 90 |
| Streptokinase | 300 IE/mL |
| Urokinase | 600 IE/mL |
| Digitoxin | 0.3 |
| Sotalol | 320 |
| Low molecular weight heparin | 18 |
No interference was seen with the drugs tested.
23
Matrix Comparisons
Methods:
The effect on quantitation of analyte in the presence of anticoagulants with the Elecsys proBNP II (updated assay) was determined on the cobas e 411 and with the Elecsys proBNP II STAT (updated assay) was determined on the cobas e 601 by comparing values obtained from native samples (single donors) drawn into Serum, Li-Heparin and K2-EDTA plasma.
Results:
Sample Matrix Comparison for Elecsys proBNP II
| Elecsys proBNP II | Li Heparin | K2-EDTA |
|---|---|---|
| Slope | ||
| [95% LCL/UCL] | 0.990 | |
| [0.981/0.997] | 1.01 | |
| [0.994/1.01] | ||
| Intercept (pg/mL) | ||
| [95% LCL/UCL] | 0.898 | |
| [-0.981/3.45] | -0.985 | |
| [-4.23/2.21] | ||
| Correlation coefficient | ||
| Pearson's r | 0.998 | 0.999 |
| Absolute Bias at 125 pg/mL | -0.391 | -0.189 |
| % Bias at 125 pg/mL | ||
| [95% LCL/UCL] | -0.3 | |
| [-1.5/1.3] | -0.2 | |
| [-2.3/2.1] | ||
| Serum/plasma pairs | 98 | 111 |
24
Method comparison
We performed a method comparison study with 1928 subjects with the biotin remediated Elecsys proBNP II STAT assay, 09315276160 (y) and the Elecsys proBNP II STAT assay, 05390109160 (x).
Image /page/24/Figure/2 description: This image is a scatter plot that compares two proBNP II STAT measurements, labeled (09315276160) and (05390109160). The plot includes a Passing-Bablok regression fit with the equation -1.60 + 1.01 * x, where n=1928. An identity line is also plotted for reference. The Pearson's r correlation coefficient is 0.999, indicating a strong positive correlation between the two measurements.
Passing Bablok Regression Fit
| Correlation | Estimate |
|---|---|
| Kendall's | |
| tau | 0.99 |
| Pearson's r | 1.00 |
25
| Passing-Bablok Regression | Predicted Relative Bias (%) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Test | |||||||||
| Method | Compariso | ||||||||
| n Method | N | Intercept | |||||||
| (95% CI) | Slope (95% | ||||||||
| CI) | 125 pg/mL | ||||||||
| (95% CI) | 300 pg/mL | ||||||||
| (95% CI) | 450 pg/mL | ||||||||
| (95% CI) | 900 pg/mL | ||||||||
| (95% CI) | 1800 | ||||||||
| pg/mL | |||||||||
| (95% CI) | |||||||||
| Biotin- | |||||||||
| remediated | |||||||||
| Elecsys | |||||||||
| proBNP II | |||||||||
| STAT | |||||||||
| (093152761 |
- | Elecsys
proBNP II
STAT
(053901091 - | 1,928 | -1.60 (-
2.09,-1.16) | 1.01
(1.00,1.01) | -0.8 (-1.0,-
0.5) | -0.0 (-
0.2,0.2) | 0.2 (-
0.1,0.4) | 0.3
(0.1,0.6) | 0.4
(0.2,0.7) |
Regression results and relative bias at selected NT-proBNP concentration levels (all, STAT)
We performed a method comparison study with 1940 subjects with the biotin remediated Elecsys proBNP II assay, 09315268160 (y) and the Elecsys proBNP II assay, 04842464160 (x).
Image /page/25/Figure/3 description: This image is a scatter plot that compares two proBNP II measurements, labeled as (09315268160) on the y-axis and (04842464160) on the x-axis. The plot includes a Passing-Bablok regression fit, represented by the equation -2.88 + 0.98 * x, with n=1940 data points. An identity line is also plotted for reference. The Pearson's r correlation coefficient is 0.999, indicating a strong positive correlation between the two measurements.
Passing Bablok Regression Fit
26
| Correlation | Estimate |
|---|---|
| Kendall's | |
| tau | 0.99 |
| Pearson's r | 1.00 |
Regression results and relative bias at selected NT-proBNP concentration levels (all, 18min)
| Passing-Bablok Regression | Predicted Relative Bias (%) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Test | |||||||||
| Method | Comparis | ||||||||
| on | |||||||||
| Method | N | Intercept | |||||||
| (95% CI) | Slope (95% | ||||||||
| CI) | 125 pg/mL | ||||||||
| (95% CI) | 300 pg/mL | ||||||||
| (95% CI) | 450 pg/mL | ||||||||
| (95% CI) | 900 pg/mL | ||||||||
| (95% CI) | 1800 | ||||||||
| pg/mL | |||||||||
| (95% CI) | |||||||||
| Biotin- | |||||||||
| remediated | |||||||||
| Elecsys | |||||||||
| proBNP II | |||||||||
| (093152681 |
- | Elecsys
proBNP II
(04842464 - | 1,940 | -2.88 (-
3.20,-2.46) | 0.98
(0.98,0.98) | -4.2 (-4.4,-
3.9) | -2.8 (-3.0,-
2.7) | -2.5 (-2.6,-
2.4) | -2.2 (-2.3,-
2.1) | -2.0 (-2.2,-
1.9) |
Conclusion: Testing demonstrated that the Elecsys proBNP II and Elecsys proBNP II STAT assays are safe and effective and are substantially equivalent to the assays cleared in K072437 and K092649. Biotin tolerance has been improved for patient safety.