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NADiA® ProsVue™ is an in-vitro diagnostic assay for determining rate of change of serum total prostate specific antigen over a period of time (slope, pg/mL per month). The NADiA® ProsVue™ assay is performed for patients having less than 0.1 ng/mL serum total PSA values (determined by standard-of-care assays that are FDA approved/cleared) in the first sample collected more than 6 weeks after radical prostatectomy. ProsVue™ slope is indicated for use as a prognostic marker in conjunction with clinical evaluation as an aid in identifying those patients at reduced risk for recurrence of prostate cancer for the eight year period following prostatectomy.

The NADiA® ProsVue™ assav is not intended for the diagnosis or for the monitoring of prostate cancer.

ProsVue™ is a two-site immunoassay utilizing an assay specific synthetic DNA sequence as a label with a PCR detection method. Calibrators, controls and samples react with a reagent containing a monoclonal PSA-specific antibody labeled with an assay-specific double-stranded DNA sequence. Then a reagent of paramagnetic microparticles coupled to a monoclonal antibody specific for another site on PSA is added and allowed to react to form a specific sandwich complex with PSA. After washing the particles to remove reactants, a reagent containing a heat-stable polymerase, specific primers, nucleotides, and a fluorescent dye is added to the washed microparticles. An Applied Biosystems® (AB) 7500 Fast Dx Real-Time PCR instrument is utilized to detect the presence of the monoclonal PSA-specific antibody labeled with an assay specific DNA sequence indicating the levels of PSA in the samples. PSA values of controls and samples are calculated in pg/mL from a calibrator dose-response plot. ProsVue slope is calculated using ProsVue Software from the calculated PSA concentrations of three patient samples collected between six weeks and 20 months post radical prostatectomy.

The assay is made up of Reporter Antibody Reagent, Target Capture Reagent. PCR Reagent, Calibrators, Directions for Use (DFU) and ProsVue Software. Wash Reagent, Sample Diluent, and a three-level assayed control set are provided separately. ProsVue users initially receive the DFU and ProsVue software, which provide instructions and quality control support for the process of sample scheduling, collection and storage. When samples are ready for testing, the user contacts Iris Molecular Diagnostics (IMD), and IMD ships the required reagents.

Here's a breakdown of the acceptance criteria and study details for the NADiA® ProsVue™ device, based on the provided text:

Acceptance Criteria and Device Performance

The document describes pre-specified performance characteristics and then presents the results of the studies conducted. It does not explicitly state "acceptance criteria" as a separate, quantitative table for clinical performance. Instead, it describes performance with results that demonstrate the device's capability. For analytical performance, the limits are established, and the device is shown to meet them.

Table of Performance Metrics and Reported Values

Study Details

1. Sample sizes used for the test set and the data provenance:

   • Clinical Test Set Sample Size: 304 patients (64 "Recurrence" and 240 "Stable").
   • Data Provenance: Patients were acquired from four clinical sites. The age range was 41 to 79 years. Racial demographics: Caucasian (88.8%), African-American (8.2%), Asian (2.0%), unknown (1.0%). Samples were collected between six weeks and 20 months post radical prostatectomy, and patients were followed for up to 17.6 years post-prostatectomy. Implied prospective follow-up of retrospectively collected samples, as patients' "clinical status ('Stable' or 'Recurrence') was documented" from existing records. The text refers to "case-cohort study design," suggesting an observational, potentially retrospective cohort where some cases of recurrence are oversampled or all cases are included from a larger cohort. No specific country of origin is explicitly stated, but the submission is to the FDA (USA), suggesting data may be from the US or internationally accepted clinical sites.

2. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

   • The document implies that ground truth for "Recurrence" or "Stable" status was established based on documented clinical status, including "positive imaging, positive biopsy, or death due to prostate cancer." It does not explicitly mention "experts" or their qualifications for establishing this ground truth. It's likely that the clinical records from the four sites, managed by medical professionals, served as the ground truth, rather than a separate panel of experts specifically adjudicating each case for the study.

3. Adjudication method for the test set:

   • No explicit adjudication method (e.g., 2+1, 3+1) is mentioned for establishing the "Recurrence" or "Stable" clinical status. The status was "documented" based on clinical outcomes.

4. 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:

   • No MRMC comparative effectiveness study was done. This device is an in-vitro diagnostic assay and software for calculating a prognostic molecular marker (PSA slope), not an imaging device typically evaluated with human readers. The clinical study evaluates the standalone performance of the assay in predicting recurrence.

5. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

   • Yes, a standalone clinical performance study was conducted. The "ProsVue linear slope was a significant predictor of reduced risk for prostate cancer recurrence in this analysis," as indicated by the univariate and multivariate Cox proportional hazards regression analyses (HR of 18.3 and 9.8 respectively). This represents the performance of the algorithm (ProsVue slope calculation) in predicting patient outcomes.

6. The type of ground truth used (expert consensus, pathology, outcomes data, etc):

   • Clinical Outcomes Data: The ground truth for the clinical study was based on documented patient clinical status: "Recurrence" (defined by positive imaging, positive biopsy, or death due to prostate cancer) or "Stable" for 8 years of follow-up.

7. The sample size for the training set:

   • The document does not explicitly state a sample size for a "training set" for the ProsVue assay or its associated software. The discussion on "Assay Performance" (measuring interval, sensitivity, linearity, precision, interfering substances, stability) describes validation studies for the analytical aspects of the assay, not a patient-level training set for a prognostic model in the machine learning sense. The clinical performance section describes the evaluation of the pre-defined ProsVue slope, not the training of a model to determine that slope or its predictive power.

8. How the ground truth for the training set was established:

   • Since no explicit training set for a prognostic model is described, there's no information on how its ground truth was established for this specific application. The analytical validation studies (e.g., for linearity, precision) used controlled laboratory samples (serum pools, spiked samples with known concentrations) to establish performance characteristics.

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