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The B12 Flex® reagent cartridge is an in vitro diagnostic test for the quantitative measurement of Vitamin B12 in human serum and plasma on the Dimension Vista® system. Measurements obtained by this device are used in the diagnosis and treatment of gastrointestinal malabsorption.

The FOL Flex® reagent cartridge is an in vitro diagnostic test for the quantitative measurement of folate in human serum and plasma on the Dimension Vista® system. Measurements obtained by this device are used in the diagnosis and treatment of megaloblastic anemia.

The LOCI 4 Calibrator is an in vitro diagnostic product for the calibration of Ferritin (FERR), Vitamin B12 (B12), and Folate (FOL) methods on the Dimension Vista® system.

B12: The Dimension Vista® Vitamin B12 method is a homogeneous, competitive chemiluminescent immunoassay based on LOCTM technology. LOCT™ reagents include two synthetic bead reagents and biotinylated intrinsic factor (IF). The first bead reagent (Chemibeads) is coated with a B12 derivative and contains a chemiluminescent dye. The second bead reagent (Sensibeads) is coated with streptavidin and contains photosensitive dye. The patient sample is pretreated with NaOH to release the serum B12 from its carrier proteins. Potassium cyanide (KCN) is added to convert all the forms of B12 into a single, cyanocobalamin form, and dicyanocobinamide is added to keep the B12 from rebinding with the carrier proteins. After the sample pretreatment, the biotinylated IF and Chemibead reagents are added sequentially to the reaction vessel. Vitamin B12 from the sample competes with the B12-Chemibead for a limited amount of biotinylated IF. Sensibeads are then added and bind to the biotin to form bead pair immunocomplexes. Illumination of the complex at 680 nm generates singlet oxygen from the Sensibeads which diffuses to the Chemibeads triggering a chemiluminescent reaction. The resulting signal is measured at 612 nm and is an inverse function of the concentration of vitamin B12 in the sample.

FOL: The Dimension Vista® Folate method is a homogenous, competitive chemiluminescent immunoassay based on LOCT™ technology. LOCT™ reagents include two synthetic bead reagents and labeled folate binding protein (FBP). The first bead reagent (Chemibeads) is coated with a folic acid derivative and contains a chemiluminescent dye. The second bead reagent (Sensibeads) is coated with streptavidin and contains photosensitive dye. Before the immunological portion of the reaction is initiated, the patient sample is pretreated with NaOH and DTT to release serum folate from endogenous folate binding protein and to maintain 5-methyl tetrahydrofolate in its reduced form. After the sample pretreatment, Chemibeads and labeled folate binding reagent are added sequentially to the reaction vessel. Folate from the patient sample competes with the folate-Chemibead for a limited amount of labeled FBP. Sensibeads are then added and bind to the biotinylated portion of the labeled FBP to form bead pair immunocomplexes. Illumination of the complex by light at 680 nm generates singlet oxygen from the Sensibeads which diffuses to the Chemibeads triggering a chemiluminescent reaction. The resulting signal is measured at 612 nm and is an inverse function of the concentration of folate in the sample.

Calibrator: The Dimension Vista® LOCI 4 Calibrator is a five level, liquid calibrator. It is packaged as a kit of 10 vials, two vials each of five levels. The product matrix is 6% bovine serum albumin with buffer, stabilizer and preservatives. Level A is zero. Levels B through E contain Ferritin, Vitamin B12, and Folate at the following target concentrations: Level A: Ferritin 0 ng/mL, B12 0 pg/mL, Folate 0.0 ng/mL; Level B: Ferritin 26 ng/mL, B12 200 pg/mL, Folate 2.5 ng/mL; Level C: Ferritin 210 ng/mL, B12 500 pg/mL, Folate 5.0 ng/mL; Level D: Ferritin 1050 ng/mL, B12 1000 pg/mL, Folate 10.0 ng/mL; Level E: Ferritin 2000 ng/mL, B12 2100 pg/mL, Folate 21.0 ng/mL. Values are assigned to new lots from a masterpool that is referenced to the WHO standard for FERR, 3 14 IS 94/572 and United States Pharmacopoeia materials for B12 and Folate.

This document describes the regulatory submission for three in-vitro diagnostic products: Dimension Vista® Vitamin B12 Flex® reagent cartridge (B12), Dimension Vista® Folate Flex® reagent cartridge (FOL), and Dimension Vista® LOCI 4 Calibrator. The submission aims to demonstrate substantial equivalence to previously cleared predicate devices.

1. Table of Acceptance Criteria and Reported Device Performance

For the Dimension Vista® B12 and FOL Flex® reagent cartridge assays, the acceptance criteria are implicitly based on demonstrating comparable performance (correlation, slope, and intercept) to their respective predicate devices. The reported performance is based on a split-sample comparison study.

2. Sample Size Used for the Test Set and Data Provenance

The test set consisted of clinical patient samples.

• B12: 124 clinical patient samples
• FOL: 110 clinical patient samples

The data provenance is not explicitly stated in terms of country of origin but is referred to as "clinical patient samples," implying retrospective. The study type is a "split sample comparison" study, which means portions of the same patient sample were tested on both the new device and the predicate device.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

This information is not provided in the document. For in-vitro diagnostic comparative studies like this, the "ground truth" for individual patient samples is usually established by the predicate device's measurement, which is considered the established method. There is no mention of independent expert review of results or a separate ground truth determination method by experts.

4. Adjudication Method for the Test Set

This information is not applicable/provided as the study design is a direct comparison to a predicate device, not a classification task requiring adjudication of expert opinions.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done, If So, What was the Effect Size of How Much Human Readers Improve with AI vs without AI Assistance

This information is not applicable. The device is an in-vitro diagnostic assay for measuring biomarkers (Vitamin B12 and Folate) and a calibrator. It is not an imaging or diagnostic aid that would involve human "readers" or AI assistance in interpretation.

6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done

The performance data presented is for the standalone performance of the Dimension Vista® B12 and FOL Flex® reagent cartridge assays, as they are fully automated in-vitro diagnostic tests. There is no human interpretation component in the measurement itself, only in the clinical application of the results.

7. The Type of Ground Truth Used

The ground truth for the performance study (comparison to predicate) was established by the measurements obtained from the legally marketed predicate devices (VB12 and FOL assays on the ADVIA Centaur® System). This is a common approach for demonstrating substantial equivalence for in-vitro diagnostic devices.

8. The Sample Size for the Training Set

This information is not provided. As an in-vitro diagnostic reagent and calibrator kit, these devices do not typically have an "algorithm" in the sense of machine learning that requires a separate training set. Their development involves R&D and validation steps, but not a distinct "training set" like an AI product would.

9. How the Ground Truth for the Training Set Was Established

This information is not provided and is generally not applicable in the context of these types of IVD reagent kits and calibrators. The development and manufacturing of these products involve rigorous quality control and calibration processes, often referenced to international standards, but not a "ground truth for a training set" in the common AI/machine learning sense.

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