(381 days)
The B.R.A.H.M.STM sFlt-1/PIGF KRYPTORTM Test System is comprised of the B . R . H . M S PIGF plus KRYPTOR assay and the B . A . H . M . S sFit-1 KRYPTOR assay.
The B R . A . H . M . S PIGF plus KRYPTOR is an automated immunofluorescent assay using Time-Resolved Amplified Cryptate Emission (TRACE™) technology for the quantitative determination of the concentration of Placental Growth Factor (PIGF) in human serum and plasma (K2 EDTA) on the B.R.A.H.M.S KRYPTOR analyzer.
The B · A · H · M · S s F t - 1 K R PTOR is an automated immunofluorescent assay using Time-Resolved Amplified Cryptate Emission (TRACE) technology for the quantitative determination of the concentration of soluble fms-like tyrosine kinase-1 (sFit-1), also known as VEGF receptor-1, in human serum and plasma (K2 EDTA) on the B.R.A.H:M:S KRYPTOR analyzer.
The B · A · H · M · S PIGF plus KRYPTOR is to be used in conjunction with the B · A · M · S sFlt-1 KRYPTOR along with other laboratory tests and clinical assessments to aid in the risk assessment of pregnant women (singleton pregnancies between gestational age 23+0 to 34+6/7weeks) hospitalized for hypertensive disorders of pregnancy (preeclampsia, chronic hypertension with or without superimposed preeclampsia, or gestational hypertension) for progression to preeclampsia with severe features (as defined by American College of Obstetricians and Gynecologists (ACOG) guidelines) within 2 weeks of presentation.
The B · A · H · M · S · F · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · PIGF plus KRYPTOR assay and the B.R.A.H.M.S sFlt-1 KRYPTOR assay.
B R . A H M . S PIGF plus KRYPTOR and B . R . H . M . STM sFit-1 KRYPTOR assays are supplied as two reagent kits that are run on the B-R-A-H-M-S KRYPTOR compact PLUS. Each kit is sufficient for 75 determinations, and is comprised of two bottled reagents:
PIGF
Cryptate conjugate: Lumi4®-Tb labeled, anti-human PlGF antibody, buffer, bovine albumin, rat immunoglobulins, bovine immunoglobulins, goat immunoglobulins, trehalose, mannitol.
XL conjugate: Cyanin 5.5 labeled, anti-human PlGF antibody, buffer, bovine albumin, rat immunoglobulins, bovine immunoglobulins, goat immunoglobulins.
sFlt-1
Cryptate conjugate: Lumi48-Tb labeled, anti-human sFlt-1 antibody, buffer, bovine albumin, bovine immunoglobulins, mouse immunoglobulins, dextran, preservative. XL conjugate: Cyanin 5.5 labeled, anti-human sFlt-1 antibody, buffer, bovine albumin, bovine immunoglobulins, mouse immunoglobulins, dextran, preservative.
The B · A · H · M · S KRYPTOR compact PLUS is an automated test platform. The analyzer consumables are:
B · R · A · H · M · S KRYPTOR compact Solution 1: ProClinTM 150 Solution
B · R · A · H · M · S KRYPTOR compact Solution 2: Potassium fluoride solution
B · R · A · H · M · S KRYPTOR compact Solution 3: Active chlorine and sodium hydroxide solution
B · R · A · H · M · S KRYPTOR compact Solution 4: Sodium hydroxide solution
B · R · A · H · M · S KRYPTOR BUFFER: Phosphate Buffer Saline
B · R · A · H · M · S KRYPTOR compact REACT: 60 plates
Also supplied and required are calibrators - single level B.R.A.H.M.S PIGF plus KRYPTOR CAL and two levels B. R. A. H. M.S sFlt-1 KRYPTOR CAL. The instrument is calibrated on a 15 day cycle, and re-calibrated with each new lot of reagents.
Also supplied and required are three levels of controls - B.R.A.H.M.S PIGF plus KRYPTOR OC Controls and B.R.A.H.M.S sFlt-1 KRYPTOR OC.
Here's a breakdown of the acceptance criteria and study details for the B.R.A.H.M.S sFlt-1/PIGF KRYPTOR Test System, based on the provided text:
Acceptance Criteria and Device Performance
The primary clinical performance acceptance criteria revolve around the device's ability to aid in the risk assessment of pregnant women for progression to preeclampsia with severe features. This is evaluated through its positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity.
Table of Acceptance Criteria and Reported Device Performance:
| Performance Metric | Acceptance Criteria (Implied by positive De Novo grant) | Reported Device Performance (95% CI) |
|---|---|---|
| Positive Predictive Value (PPV) | Sufficiently high to indicate a clinically useful risk assessment. | 65% (59.3, 70.6) |
| Negative Predictive Value (NPV) | Sufficiently high to indicate a clinically useful risk assessment. | 96% (92.9, 97.6) |
| Sensitivity | Sufficiently high to identify true positives. | 94% (89.1, 96.3) |
| Specificity | Sufficiently high to identify true negatives. | 75% (70.2, 79.0) |
| Positive Likelihood Ratio (PLR) | Implied to be clinically useful. | 3.72 (3.11, 4.46) |
| Negative Likelihood Ratio (NLR) | Implied to be clinically useful. | 0.09 (0.05, 0.15) |
Note: The document does not explicitly state numerical acceptance criteria prior to the study results. The granting of the De Novo request implies that the reported performance metrics were deemed acceptable by the FDA for the device's intended use.
Study Proving Device Meets Acceptance Criteria
The study described is the PRAECIS (Preeclampsia Risk Assessment: Evaluation of Cut-offs to Improve Stratification, Identification and Validation of a Cut-off for the Ratio of Soluble Fms-like Tyrosine Kinase-1 to Placental Growth Factor (sFlt-1/PlGF) to Stratify Risk in Pregnant Women with Hypertensive Disorders of Pregnancy) clinical study.
1. Sample Size Used for the Test Set and Data Provenance:
- Sample Size: 556 enrollments (from 520 patients, with some patients enrolled multiple times).
- Data Provenance: Prospective, multicenter, blinded, non-interventional study conducted across 18 sites in the US.
2. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:
- Number of Experts: A panel of 3 independent obstetricians.
- Qualifications: "Obstetricians" is the only qualification mentioned. No specific experience levels (e.g., years of experience) are provided.
3. Adjudication Method for the Test Set:
- Method: A central adjudication committee (panel of 3 independent obstetricians) was assembled to review data and arrive at consensus regarding each patient's diagnoses for the development of sPE following the 2013 ACOG clinical practice guidelines. This indicates a consensus-based adjudication.
4. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done:
- No, an MRMC comparative effectiveness study was not done. This study evaluates an in vitro diagnostic (IVD) test system (measurement of sFlt-1 and PlGF levels and their ratio) rather than an AI-assisted imaging diagnosis system where human readers would be involved in interpreting images. Therefore, the concept of "human readers improving with AI vs. without AI assistance" does not apply here.
5. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
- Yes, in essence, a standalone evaluation was performed for the device's output. The "algorithm" here is the immunofluorescent quantitative assay that measures sFlt-1 and PIGF concentrations and calculates their ratio. The clinical performance (PPV, NPV, sensitivity, specificity) is based on comparing the device's calculated ratio (using a defined cutoff of >40 for 'high risk' and
N/A