(187 days)
The Roche Elecsys Anti-HAV immunoassay is used for the in vitro qualitative detection of total antibodies (IgM and IgG) to hepatitis A virus in human serum and plasma (K2-EDTA). The assay is intended for use as an aid in the laboratory diagnosis of past or acute/recent hepatitis A infection.
Assay results, in conjunction with other laboratory results and clinical information, may be used to provide presumptive evidence of infection with hepatitis A virus in persons with signs or symptoms of hepatitis and in persons at risk for hepatitis A infection, or used as an aid to determine the presence of antibody response to HAV in vaccine recipients.
The electrochemiluminescence immunoassay "ECLIA" is intended for use on Elecsys and cobas e immunoassav analyzers.
Elecsys PreciControl Anti-HAV is used for the quality control of the Elecsys Anti-HAV immunoassay on the Elecsys and cobas e immunoassay analyzers.
The Elecsys anti-HAV test is a qualitative assay based on electrochemiluminescence immunoassay "ECLIA" technology. The Elecsys anti-HAV test utilizes a competitive immunoassay format in which sample anti-HAV antibody competes with biotinylated and ruthenvlated anti-HAV monoclonal antibodies for a limited amount of cell culture-derived HAV antigen. The sample antibody and the HAV antigen react in the first incubation. The biotinylated antibodies and ruthenium complex® -labeled antibodies specific for HAV antigen are added in the second incubation together with streptavidin-coated magnetic microparticles. The unbound HAV antigen reacts with the modified antibodies and the resulting immune complexes are bound to the solid phase through a biotinstreptavidin interaction. If all HAV antigens are complexed by sample anti-HAV antibody during the first incubation, no modified/labeled immune complexes are formed and captured during the second incubation.
Following the second incubation, the reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are removed by elution with ProCell. Application of a voltage to the electrode induces chemiluminescent emission from the captured immune complexes which is measured by a photomultiplier. The level of signal detected by the system decreases as the concentration of the anti-HAV antibody target present in a patient sample increases.
Results are determined via a calibration curve which is generated by 2-point calibration on the instrument and a master curve provided via the reagent barcode. The calibration process converts the output so that low levels of sample anti-HAV antibodies are expressed by low output and high levels of antibody are expressed by high output. These outputs are finally interpreted on a qualitative basis around the established cut-off output.
Here's a breakdown of the acceptance criteria and study information for the Elecsys® Anti-HAV Assay, based on the provided 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are generally implied by the performance metrics reported, as the submission concludes that the information "supports a substantial equivalence decision." This means the reported performance met the FDA's expectations for equivalence to the predicate device.
| Performance Metric | Acceptance Criteria (Implied/General) | Reported Device Performance |
|---|---|---|
| Analytical Performance | ||
| Precision | Acceptable %CV for repeatability and intermediate precision, typically within established guidelines (e.g., CLSI EP15-A2/EP5-A2). | Elecsys 2010: |
- PC Anti-HAV 1: Repeatability CV 1.8%, Int. Precision CV 3.1%
- PC Anti-HAV 2: Repeatability CV 3.2%, Int. Precision CV 4.5%
- HSP 1, 2, 3: Repeatability CVs 2.5-3.4%, Int. Precision CVs 3.0-4.6%
MODULAR ANALYTICS E170: - PC Anti-HAV 1: Repeatability CV 1.5%, Int. Precision CV 5.5%
- PC Anti-HAV 2: Repeatability CV 2.3%, Int. Precision CV 5.8%
- HSP 1, 2, 3: Repeatability CVs 1.1-3.5%, Int. Precision CVs 4.3-5.6%
Reproducibility (Overall within-site and between-site CVs also provided, e.g., Overall PPA/NPA > 90%) |
| Detection Limits (LoD) | Lowest amount of analyte detectable with 95% probability, set at 6.00 IU/L. | Elecsys 2010 / cobas e 411: LoD = 5.155 IU/L
MODULAR ANALYTICS E170 / cobas e 601: LoD = 2.994 IU/L
Reported in labeling: 6.00 IU/L for both types. |
| Analytical Specificity (Cross-reactivity) | Minimal false positives with common interfering conditions/diseases. | 177 samples from 15 subgroups tested: 174 non-reactive, 3 discordant with predicate. No HAMA effect found. |
| Analytical Specificity (Interference) | Recovery of positive samples within ± 20 % of initial value. | Unaffected by icterus (90-95%) with a legally marketed predicate device. | Overall PPA: 98.12% (96.46% to 99.14% CI) |
| Overall Negative Percent Agreement (NPA) with Predicate | High agreement (e.g., >90-95%) with a legally marketed predicate device. | Overall NPA: 97.37% (95.70% to 98.52% CI) |
| Seroconversion Sensitivity | Agreement with predicate and vendor data for seroconversion panels. | Elecsys Anti-HAV assay showed similar performance to comparator (Abbott AxSym HAV AB-2.0) based on post bleed day of earliest reactive/last positive result for 3 panels. |
| Method Comparison (between platforms) | High PPA and NPA (e.g., >95%) between the Elecsys 2010 and MODULAR ANALYTICS E170. | PPA: 96.8% (91.0% to 99.3% CI)
NPA: 98.0% (93.0% to 99.8% CI)
Pearson's regression correlation: 0.9951 (slope 1.024, intercept -0.555). |
2. Sample Sizes Used for the Test Set and Data Provenance
- Clinical Performance Study (Comparison with Predicate):
- Total Samples: 1050 samples (after excluding one concordantly equivocal sample).
- Cohort Breakdown:
- Subjects for whom routine hepatitis A testing had been ordered.
- Hospitalized patients.
- Subjects at increased risk for hepatitis.
- Subjects with signs and symptoms of hepatitis.
- Subjects characterized with acute hepatitis A.
- Subjects below the age of 21 years (pediatric/adolescents).
- Specific numbers per cohort are detailed in the tables (e.g., 197 for Routine HAV Testing, 219 for Hospitalized, etc., summing to the overall total).
- Data Provenance: Multi-center study conducted in the U.S. (across 3 sites: BW, WU, JH). Samples were a mix of prospective and retrospective collections. All samples stored frozen before shipment.
- Analytical Specificity (Cross-reactivity): 177 samples from 15 potentially cross-reactive subgroups.
- Analytical Specificity (Interference): Native human serum pools, and 18 commonly used pharmaceuticals and folic acid.
- Prevalence Study (Expected Values): 602 patients (300 from high prevalence region, Western U.S. (New Mexico); 302 from low prevalence region, Eastern U.S. (Indiana)). This was a prospective study.
- Seroconversion Sensitivity: 3 seroconversion panels.
- Method Comparison (between platforms): 202 samples (100 non-reactive from prevalence cohort, 53 reactive from clinical cohorts, 49 reactive from Roche R&D archive).
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not explicitly provided in the summary. The "ground truth" for clinical performance is established by comparing the Elecsys Anti-HAV assay results against an "FDA-cleared reference method" (the predicate device, Abbott AxSym HAVAB® 2.0). However, the summary does not specify if or how many human experts were involved in interpreting results from either the new device or the predicate to establish a "ground truth" in cases of discordance, or to confirm clinical status. The study relies on the predicate device's established performance and classification of samples.
4. Adjudication Method for the Test Set
The summary does not explicitly describe an adjudication method involving human experts for the test set. The clinical performance section states that the assay's performance was determined by agreement with the predicate device, which indicates a direct comparison rather than a human adjudication process to "resolve" discordant results. For "borderline" results from the Elecsys Anti-HAV assay (18.0
§ 866.3310 Hepatitis A virus (HAV) serological assays.
(a)
Identification. HAV serological assays are devices that consist of antigens and antisera for the detection of hepatitis A virus-specific IgM, IgG, or total antibodies (IgM and IgG), in human serum or plasma. These devices are used for testing specimens from individuals who have signs and symptoms consistent with acute hepatitis to determine if an individual has been previously infected with HAV, or as an aid to identify HAV-susceptible individuals. The detection of these antibodies aids in the clinical laboratory diagnosis of an acute or past infection by HAV in conjunction with other clinical laboratory findings. These devices are not intended for screening blood or solid or soft tissue donors.(b)
Classification. Class II (special controls). The special control is “Guidance for Industry and FDA Staff: Class II Special Controls Guidance Document: Hepatitis A Virus Serological Assays.” See § 866.1(e) for the availability of this guidance document.