(137 days)
DRx® Qt. hCG is a rapid, single-use, point-of-care device for the quantitative measurement of human chorionic gonadotropin (total ßhCG) in capillary and venous whole blood samples. The device is for professional use as an aid in the assessment of pregnancy status.
The DRx® Ot. hCG device is a single-use, disposable four-channel reflectance photometer integrated with dry reagent chemistry strips and contained within a sealed plastic case. Each unit consists of:
. an optics subassembly that also supports the reagent strips
- a printed circuit board that includes a microprocessor, analog . electronics, battery clips, batteries, silicon diode photodetectors, and j light emitting diodes (LEDs)
- a plastic molded part ("spider") that supports the liquid crystal display ● (LCD), the sample pad and the auto start leads, and also provides optical shielding
- two reagent strips .
- whole blood separation chemistry pad ●
- a desiccant
- liquid crystal display (LCD)
Both test strips are lateral flow immunoassays for measuring hCG between zero and 10,000 mIU/mL. In both strips, a blue color is measured in discrete test zones. The test zones are the areas where the specific reactions occur and concentrations are measured.
The whole blood separation mechanism occurs when the whole blood ~ sample reaches the sample pad and immobilizes the red blood cells. As a result, the plasma freely migrates by capillary action onto the assay strips to complete the final reactions. The hCG reaction proceeds as follows: anti-hCG antibody, conjugated to blue microparticles, migrate across the strip upon the addition of whole blood sample. The amount of blue microparticles captured on the test zones is proportional to the amount of hCG in the sample.
The LEDs and silicon photodetectors compare the reflectances of the color intensities before and after the sample addition. Based on the calibration parameters stored in memory, the numerical concentrations of hCG is calculated. The final assay results are expressed in mIU/mL hCG.
The Metrika, Inc. DRx® Qt. hCG device is a rapid, single-use, point-of-care device for the quantitative measurement of human chorionic gonadotropin (total ßhCG) in capillary and venous whole blood samples, intended for professional use to assess pregnancy status.
Here's an analysis of its acceptance criteria and the study that proves the device meets those criteria:
1. Table of Acceptance Criteria and Reported Device Performance:
The document doesn't explicitly state "acceptance criteria" through numerical targets for the comparative study. Instead, it presents the results of a comparative study against a predicate device and demonstrates strong correlation, implying that the performance achieved is considered acceptable for substantial equivalence. For analytical performance, criteria are implied by the confirmed ranges and specificities.
| Performance Metric | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Analytical Sensitivity | Sensitive to low hCG levels | Sensitive to 5 mIU/mL hCG. |
| Analytical Specificity | Not affected by common interferents; specific for total beta hCG subunit | Not affected by the addition of potential interferents (biological compounds and therapeutic agents found routinely in blood). Not affected by potential cross-reactants (hLH, hFSH, hTSH). Specific for total beta hCG subunit present as intact hCG or free beta subunit. |
| Linearity | Wide dynamic range for hCG measurement | Confirmed dynamic ranges of 5 to 10,000 mIU/mL for hCG. |
| Accuracy (Venous Blood vs. Predicate) | High correlation with predicate device | Based on 96 samples, the linear regression equation was y = 0.92x + 20 with a Correlation Coefficient of 0.98. This indicates very high agreement with the predicate. |
| Accuracy (Fingerstick Blood vs. Predicate) | High correlation with predicate device | Based on 63 samples, the linear regression equation was y = 1.05x + 8 with a Correlation Coefficient of 0.96. This indicates high agreement with the predicate. |
| Accuracy (DRx® Venous vs. DRx® Fingerstick) | High correlation between sample types | Based on 63 samples, the linear regression equation was y = 1.06x - 6 with a Correlation Coefficient of 0.99. This demonstrates strong equivalence between venous and fingerstick whole blood samples when tested on the DRx® Qt. hCG device. |
| Precision | Acceptable coefficients of variation (CV%) | The coefficients of variation ranged from 8.3% to 15.1% across three sites when tested with a 3-level whole blood precision panel (low, middle, and high hCG levels) on a single day. The specific "acceptable" range is not given, but these values are presented as evidence of suitable precision for point-of-care devices in this context. |
2. Sample Sizes Used for the Test Set and Data Provenance:
- Accuracy (Venous Blood vs. Predicate): 96 venous whole blood samples.
- Accuracy (Fingerstick Blood vs. Predicate): 63 matched whole blood capillary (fingerstick) samples.
- Accuracy (DRx® Venous vs. DRx® Fingerstick): 63 matched venous and fingerstick samples (implicitly the same 63 used for the fingerstick vs. predicate comparison, as they were "matched").
- Precision: Not explicitly stated as a single number per level, but tested with a "3-level whole blood precision panel" (low, middle, and high hCG levels) by repeat testing on a single day.
- Data Provenance:
- For accuracy studies, samples were collected at "four 'POL' clinical sites and in-house" for venous samples, and at "clinical sites" for fingerstick samples. This indicates the data is prospective and collected from multiple real-world clinical settings.
- The country of origin is not explicitly stated, but given the submission is to the FDA in the US, it is reasonable to assume the clinical sites were located within the US.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:
The ground truth for the accuracy studies was established by comparison to a predicate device, the Stratus® ßhCG, not by expert consensus. Therefore, the concept of "number of experts" or their qualifications for establishing ground truth does not directly apply here. The predicate device's results serve as the reference.
4. Adjudication Method for the Test Set:
Not applicable, as the ground truth was established by a single, commercially available predicate device (Stratus® ßhCG) which served as the reference method. There was no expert adjudication process described for reconciling discrepancies.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done:
No, an MRMC comparative effectiveness study was not done. The study focused on the device's analytical performance (accuracy, precision, sensitivity, linearity, specificity) compared to a predicate device, and the equivalence of different sample types (venous vs. fingerstick), not on the improvement of human readers with AI assistance. The DRx® Qt. hCG is a standalone diagnostic device, not an AI-assisted interpretation tool for human readers.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done:
Yes, a standalone performance study was done. The DRx® Qt. hCG is described as "a rapid, single-use, point-of-care device for the quantitative measurement," indicating it provides a direct numerical result without human interpretation of images or complex data that would involve a "human-in-the-loop." The study evaluates the device's output (hCG concentration) directly against a predicate method.
7. The Type of Ground Truth Used:
The ground truth for the accuracy assessment was established using comparison to a legally marketed predicate device (Stratus® ßhCG). This is a common method for demonstrating substantial equivalence in medical device submissions where an established gold standard instrument exists.
8. The Sample Size for the Training Set:
The document does not specify a separate "training set" size. This type of submission (510(k) summary for a diagnostic device) typically focuses on the validation of the finalized device. The device's internal calibration parameters are mentioned ("Based on the calibration parameters stored in memory"), implying that some data was used for initial development and calibration, but the size and nature of this "training set" are not detailed in this summary.
9. How the Ground Truth for the Training Set was Established:
As the document does not explicitly mention a "training set" in the context of machine learning or AI, the concept of establishing ground truth for it as typically understood is not applicable. The device relies on "calibration parameters stored in memory" which would have been established through a manufacturing and calibration process, likely using known concentration standards, rather than expert-labeled data for training an algorithm.
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M = T R I K A
Metrika, Inc. 510 Oakmead Parkway Sunnyvale, CA 94086 main 408 524 2255 fax 408 524 2252
510(k) SUMMARY
This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.
The assigned 510(k) number is K991532.
| 807.92 (a)(1): Name: | Metrika, Inc. |
|---|---|
| Address: | 510 Oakmead Parkway |
| Sunnyvale, CA 94086 | |
| Phone: | (408) 524-2255 |
| FAX: | (408) 524-2252 |
| Contact: | Stephen J. Hardt |
807.92 (a)(2): Device name- trade name and common name, and classification
| Trade name (Device): | DRx® Qt. hCG |
|---|---|
| Common Name (Device): | whole blood hCG immunoassay system |
| Classification (Device): | 21 CFR 862.1155 |
| Trade name (Control): | DRx® Qt. hCG Control Set |
|---|---|
| Common Name (Control): | assayed hCG control |
Classification (Control): 21 CFR 862.1660
807.92 (a)(3): Identification of the legally marketed predicate device
(Device)
DRx® Qt. hCG is substantially equivalent to the commercially available predicate device, Stratus® ßhCG (Dade Behring Inc., Miami, FL). DRx Ot. hCG reports a single result without additional off-line dilutions or whole blood specimen manipulations. Stratus® requires dilutions of samples greater than 1000 mIU/mL and sample centrifugation (for plasma) prior to evaluations in order to report the final result.
(Control)
Dade® Immunoassay Controls Comprehensive Tri-Level Name: Manufacturer: Dade International, Inc.
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807.92 (a)(4): Device Description
(Device)
The DRx® Ot. hCG device is a single-use, disposable four-channel reflectance photometer integrated with dry reagent chemistry strips and contained within a sealed plastic case. Each unit consists of:
. an optics subassembly that also supports the reagent strips
- a printed circuit board that includes a microprocessor, analog . electronics, battery clips, batteries, silicon diode photodetectors, and j light emitting diodes (LEDs)
- a plastic molded part ("spider") that supports the liquid crystal display ● (LCD), the sample pad and the auto start leads, and also provides optical shielding
- two reagent strips .
- whole blood separation chemistry pad ●
- a desiccant
- liquid crystal display (LCD)
Both test strips are lateral flow immunoassays for measuring hCG between zero and 10,000 mIU/mL. In both strips, a blue color is measured in discrete test zones. The test zones are the areas where the specific reactions occur and concentrations are measured.
The whole blood separation mechanism occurs when the whole blood ~ sample reaches the sample pad and immobilizes the red blood cells. As a result, the plasma freely migrates by capillary action onto the assay strips to complete the final reactions. The hCG reaction proceeds as follows: anti-hCG antibody, conjugated to blue microparticles, migrate across the strip upon the addition of whole blood sample. The amount of blue microparticles captured on the test zones is proportional to the amount of hCG in the sample.
The LEDs and silicon photodetectors compare the reflectances of the color intensities before and after the sample addition. Based on the calibration parameters stored in memory, the numerical concentrations of hCG is calculated. The final assay results are expressed in mIU/mL hCG.
(Control)
The DRx® Qt. hCG Control Set is a bovine plasma-based, liquid, 2-level control set to be used in quality control procedures with the DRx® Qt. hCG test. The assayed control set is used for evaluating precision and systematic analytical deviations that may arise from device variations.
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807.92 (a)(5): Intended use
(Device)
The DRx® Ot. hCG is a rapid, single-use, point-of-care device for the quantitative measurement of human chorionic gonadotropin (total ßhCG) in capillary and venous whole blood. The device is for professional use as an aid in the assessment of pregnancy status.
(Control)
The DRx® Qt. hCG Control Set is a two level, assayed, liquid control containing human chorionic gonadotropin for the evaluation of precision and accuracy of the DRx® Qt. hCG device.
807.92 (a)(6): Technological Similarities and Differences to the Predicate
| CHARACTERISTIC | DRx® Qt. hCG | Stratus® βhCGK850570 |
|---|---|---|
| Intended Use | DRx® Qt. hCG is a rapid, single-use, point-of-care device for thequantitative measurement ofhuman chorionic gonadotropin(total βhCG) in capillary andvenous whole blood samples.The device is for professional useas an aid in the assessment ofpregnancy status. | The Stratus βhCG FluorometricEnzyme Immunoassay is forquantitative determination oftotal beta human chorionicgonadotropin (βhCG) levels inserum and plasma for thedetection of pregnancy. |
| Analyte(s) | hCG (mIU/mL)WHO 3rd IS 75/537 | hCG (mIU/mL)WHO 3rd IS 75/537 |
| Testing Matrix(Specimen Type) | Plasma(after integrated red blood cellseparation) | Serum and plasma |
| Testing Environment | professional use | professional use |
| Risk to Patient | not a sole discriminant; hCGresults are interpreted along withmedical histories and otherdiagnostic procedures. | not a sole discriminant; hCGresults are interpreted along withmedical histories and otherdiagnostic procedures. |
Similarities Between DRx® Ot. hCG and Stratus® BhCG
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807.92 (a)(6): Technological Similarities and Differences to the Predicate (continued)
| CHARACTERISTIC | DRx® Qt. hCG | Stratus® βhCG K850570 |
|---|---|---|
| Methodology/TestingPlatforms | DRx® Qt. hCG is a four channel, reflectance photometer (plus an internal reference channel) with integral dry chemistry strips. | Stratus® βhCG is a Fluorometric Enzyme Immunoassay. |
| Reportable Ranges | 5 to 10,000 mIU/mL | 2 to 1000 mIU/mL |
| Dilutions | Not required | Required for samples greater than 1000mIU/mL hCG |
| Specimen Processing | Not required(straight addition of whole blood specimen into device for testing) | Required(centrifugation of whole blood specimen to obtain serum or plasma before testing) |
Differences Between DRx® Qt. hCG and Stratus® ßhCG
:
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807.92 (a)(6): Technological Similarities and Differences to the Predicate (continued)
| and Dade® Immunoassay Controls Comprehensive Tri-Level | ||
|---|---|---|
| CHARACTERISTIC | DRx® Qt. hCG Control Set | Dade® ImmunoassayControls ComprehensiveTri-LevelK860906 |
| Intended Use | The DRx® Qt. hCG Control Set isa two level, assayed, liquid controlcontaining human chorionicgonadotropin for the evaluation ofprecision and accuracy of theDRx® Qt. hCG device. | Dade® Immunoassay ControlsComprehensive Tri-Level areintended to assist inmonitoring accuracy andprecision in clinical assays. |
| Testing Environment | professional use | professional use |
| Test Method | quantitative | quantitative |
Similarities Between DRx® Qt. hCG Control Set d Dade® Immunoassay Controls Comprehensive Tri-Level
Differences Between DRx® Qt. hCG Control Set
and Dade® Immunoassay Controls Comprehensive Tri-Level
| CHARACTERISTIC | DRx ® Qt. hCG Control Set | Dade® Immunoassay Controls ComprehensiveTri-LevelK860906 |
|---|---|---|
| Analyte(s) | hCG | (Various constituents), e.g.Acetaminophen LidocaineDigoxin TSHVitamin B12 hGHFSH PSAhCG hLH, etc. |
| Matrix | Liquid, bovine plasma-based matrix with spiked human-based analyte | Lyophilized, human source materials |
The differences in the two testing platforms for either devices or control materials do not raise new issues of safety and effectiveness.
ﮐﮯ ﻣ
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807.92 (b)(1): Brief Description of Nonclinical Data (Device)
Studies were conducted that evaluated hCG for analytical sensitivity. analytical specificity, and linearity.
Sensitivity studies demonstrated that the device is sensitive to 5 mIU/mL hCG.
DRx® Qt. hCG results were not affected by the addition of potential interferents such as biological compounds and therapeutic agents found routinely in blood. In addition, DRx® Qt. hCG results were not affected by potential cross/reactants similar to alpha hCG homology such as hLH, hFSH, and hTSH. The device is specific for total beta hCG subunit present as intact hCG or free beta subunit.
Linearity studies confirmed dynamic ranges of 5 to 10,000 mIU/mL for hCG.
807.92 (b)(2): Brief Description of Clinical Data (Device)
Accuracy was evaluated by comparative testing between DRx Ot. hCG and Stratus® BhCG as the predicate method. Ninety-six (96) venous whole blood samples were assayed by DRx® Ot. hCG among four "POL" clinical sites and in-house, and by the predicate method. In addition, 63 matched whole blood capillary (fingerstick) samples were collected at the These fingerstick samples were compared to venous clinical sites. samples tested in DRx® Qt. hCG assay to demonstrate equivalence of sample. The data are summarized below (predicate method = X-axis).
| n samples | Linear RegressionEquation | CorrelationCoefficient | |
|---|---|---|---|
| hCG(venous compared to predicate) | 96 | $y = 0.92x + 20$ | 0.98 |
| hCG(fingerstick compared to predicate) | 63 | $y = 1.05x + 8$ | 0.96 |
| hCG(DRx® venous vs. DRx® fingerstick) | 63 | $y = 1.06x - 6$ | 0.99 |
CLINICAL LINEAR REGRESSION DATA
Precision was evaluated at three sites by repeat testing of a 3-level whole blood precision panel (low, middle, and high hCG levels) on a single day. The coefficients of variation ranged from 8.3% to 15.1% across the three sites.
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807.92 (b)(3): Conclusions from Nonclinical and Clinical Testing (Device)
Studies demonstrated substantial equivalence between DRx® Qt. hCG and an existing product already being marketed in terms of accuracy and precision. Sensitivity and linearity studies confirmed the assay's reportable range, and interference substance studies confirmed the assay's specificity.
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Image /page/7/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the top half of the circle. Inside the circle is a stylized image of three human profiles facing to the right, resembling a bird-like shape.
SEP 1 7 1999
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
Mr. Ya-Chen Hsu Clinical Research Associate Metrika, Inc. 510 Oakmead Parkway Sunnyvale, California 94086
Re: K991532
Trade Name: DRx® Qt. hCG Regulatory Class: II Product code: DHA Regulatory Class: I reserved Product Code: JJX Dated: July 20, 1999 Received: July 21, 1999
Dear Mr. Hsu:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we 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). You may, therefore, market the device, subject to the general controls provisions of the Act. 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.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (OS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions, Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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Page 2
Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770) 488-7655.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
Steven Autman
Steven I. Gutman, M.D, M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number: K991532
Device Name: DRx® Qt. hCG
INDICATIONS FOR USE
DRx® Qt. hCG is a rapid, single-use, point-of-care device for the quantitative measurement of human chorionic gonadotropin (total ßhCG) in capillary and venous whole blood samples. The device is for professional use as an aid in the assessment of pregnancy status.
Device Name: DRx® Qt. hCG Control Set
INDICATIONS FOR USE
The DRx® Qt. hCG Control Set is a two level, assayed, liquid control containing human chorionic gonadotropin for the evaluation of precision and accuracy of the DRx Ot. hCG device.
Jean Cooper
(Division Sign-off)
Division of Clinical Laboratory Devi
510(k) Number K991532
(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use
(Per 21 CFR 801.109)
✓
OR
Over-The-Counter Use (Optional Format 1-2-96)
§ 862.1155 Human chorionic gonadotropin (HCG) test system.
(a)
Human chorionic gonadotropin (HCG) test system intended for the early detection of pregnancy —(1)Identification. A human chorionic gonadotropin (HCG) test system is a device intended for the early detection of pregnancy is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class II.(b)
Human chorionic gonadotropin (HCG) test system intended for any uses other than early detection of pregnancy —(1)Identification. A human chorionic goadotropin (HCG) test system is a device intended for any uses other than early detection of pregnancy (such as an aid in the diagnosis, prognosis, and management of treatment of persons with certain tumors or carcinomas) is intended to measure HCG, a placental hormone, in plasma or urine.(2)
Classification. Class III.(3)
Date PMA or notice of completion of a PDP is required. As of the enactment date of the amendments, May 28, 1976, an approval under section 515 of the act is required before the device described in paragraph (b)(1) may be commercially distributed. See § 862.3.