(165 days)
The Homocysteine Enzymatic Assay is an in vitro test for the quantitative determination of total L-homocysteine in human serum and plasma on Roche/Hitachi cobas c systems. The assay can assist in the diagnosis of patients suspected of having hyperhomocysteinemia or homocystinuria.
The Homocysteine Calibrator Kit is intended for use in the calibration of quantitative Roche methods on Roche clinical chemistry analyzers as specified in the value sheets.
The Homocysteine Control Kit is intended for use in quality control by monitoring accuracy and precision for the quantitative methods as specified in the value sheets.
Assay: The Homocysteine Enzymatic Assay is based on an enzyme cycling assay principle that assesses the co-substrate conversion product. In this assay, oxidized homocysteine (Hcy) is first reduced to free Hcy which then reacts with a co-substrate, S-adenosylmethionine, to form methionine and S-adenosylhomocysteine (SAH), catalyzed by a Hcy S-methyltransferase. SAH is assessed by coupled enzyme reactions where SAH is hydrolyzed into adenosine (Ado) and Hcy by SAH hydrolase, and Hcy is cycled into the Hcy conversion reaction to form a reaction cycle that amplifies the detection signal. The formed Ado is immediately hydrolyzed into inosine and ammonia which reacts with glutamate dehydrogenase with concomitant conversions of NADH to NAD*. The concentration of Hcy in the sample is indirectly proportional to the amount of NADH converted to NAD which is measured spectrophotometrically at 340 nm.
Calibrator: The Homocysteine Calibrator Kit is a liquid, ready-for-use calibrator based on human serum. It is a single level calibrator with lot specific values and diluted on board the analyzer to create a 5-point calibration curve.
Control: The Homocysteine Control Kit consists of two ready-for-use controls based on human serum. The adjusted concentrations of the control components are in the low range for Control 1 and in the elevated range for Control 2.
This response summarizes the provided 510(k) Summary for the Homocysteine Enzymatic Assay, Calibrator Kit, and Control Kit. The document primarily focuses on demonstrating substantial equivalence to predicate devices rather than detailing a specific study to prove the device meets acceptance criteria. Therefore, some requested information, particularly regarding ground truth establishment, expert qualifications, adjudication methods, and MRMC studies, is not present in the provided text.
Here's the breakdown of the available information:
1. Table of Acceptance Criteria and Reported Device Performance
The 510(k) Summary presents a comparison of the draft device's features, including performance characteristics, against a predicate device. This comparison implicitly serves as a form of acceptance criteria, where the new device's performance is deemed acceptable if it is substantially equivalent to the cleared predicate.
| Feature / Acceptance Criteria (Implicit from Predicate) | Reported Device Performance (Draft Device) |
|---|---|
| Intended Use | In vitro test for quantitative determination of L-homocysteine in human serum and plasma on Roche/Hitachi cobas c systems. Assists in diagnosis of hyperhomocysteinemia or homocystinuria. |
| Sample Types | Serum, Lithium Heparin, K2EDTA, and K3EDTA |
| Instrument Platform | cobas c 501 |
| Calibrator | Homocysteine Calibrator; single level, diluted to form a 5-point calibration |
| Calibration Frequency | Every 7 days, after reagent lot change, and as required following quality control procedures |
| Calibration Mode | RCM |
| Controls | Homocysteine Controls |
| Reagent Active Ingredients | R1: S-adenosylmethionine, TCEP, 2-oxoglutarate, NADH; R2: homocysteine S-methyltransferase, glutamate dehydrogenase, casein (bovine); R3: adenosine deaminase (bovine), S-adenosyl-homocysteine hydrolase, casein (bovine) |
| Reagent Stability (Unopened) | 2-8 °C until expiration date |
| Reagent Stability (On-board in use) | 4 weeks |
| Measuring Range | 3 – 50 µmol/L |
| Lower Limits of Measure | LoB = 3 µmol/L; LoD = 3 µmol/L |
| Precision (CV) | Hcy Control 1: Mean 12.2 µmol/L, CV Repeatability 1.5%, CV Intermediate Precision 2.1% Hcy Control 2: Mean 39.1 µmol/L, CV Repeatability 1.8%, CV Intermediate Precision 2.0% Human serum 1: Mean 8.26 µmol/L, CV Repeatability 2.0%, CV Intermediate Precision 2.3% Human serum 2: Mean 13.1 µmol/L, CV Repeatability 1.8%, CV Intermediate Precision 2.1% Human serum 3: Mean 30.0 µmol/L, CV Repeatability 1.4%, CV Intermediate Precision 1.8% Human serum 4: Mean 44.4 µmol/L, CV Repeatability 2.0%, CV Intermediate Precision 2.2% |
| Expected Values | US: 15 µmol/L cut-off for normal in adults. Europe: 12 µmol/L cut-off for normal in adults. |
| Interferences | Methotrexate, carbamazepine, phenytoin, nitrous oxide, anticonvulsants, or 6-azuridine triacetate may cause higher Hcy levels. S-Adenosylhomocysteine (SAH) causes positive interference but is at sub-nmol/L in normal plasma. No significant interference from Icterus, Hemolysis (up to H index 100), Lipemia (up to L index 250), Triglycerides (up to 1790 mg/dl). No interference from common drug panels, Glutathione (0.5 mmol/L), Cystathionine (100 µmol/L), and Pyruvate (0.5 mmol/L). 3-deazaadenosine inhibits key enzymes. Gammopathy (IgM) may cause unreliable results. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the sample size for a "test set" in the context of a clinical validation study. The precision data provided refers to "Hcy Control 1," "Hcy Control 2," and "Human serum 1, 2, 3, 4." The number of samples for each of these categories is not specified.
The data provenance (country of origin, retrospective/prospective) is not mentioned in the provided text.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not available in the provided 510(k) summary. The document focuses on analytical performance characteristics rather than clinical diagnostic accuracy requiring ground truth established by experts.
4. Adjudication Method for the Test Set
This information is not provided.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
An MRMC study is typically associated with imaging devices or diagnostic tests where human interpretation is a critical component. This device is an in vitro diagnostic (IVD) assay for quantitative determination of a biomarker. Therefore, an MRMC comparative effectiveness study involving human readers would not be applicable or expected for this type of device, and no such study is mentioned.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done
The provided data pertains to the analytical performance of the automated Homocysteine Enzymatic Assay on Roche/Hitachi cobas c systems. This inherently represents standalone (algorithm only/instrument only) performance, as it measures the assay's ability to precisely and accurately quantify Homocysteine in biological samples. The reported precision and interference studies demonstrate this standalone performance.
7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)
For the analytical performance studies (e.g., precision, measuring range, interference), the "ground truth" is established by:
- Known concentrations: For controls and calibrators, the concentrations are precisely manufactured and known.
- Reference methods or accepted analytical techniques: For validation of accuracy and linearity, comparison to established reference methods or highly accurate laboratory methods would typically be employed, although specific details are not provided in this summary.
- Spiked samples: Interference studies often involve spiking samples with known interferents to assess their effect.
There is no mention of expert consensus, pathology, or outcomes data as a ground truth for the performance claims presented in this analytical device summary.
8. The Sample Size for the Training Set
This information is not available in the provided 510(k) summary. The document describes an enzymatic assay, not an AI or machine learning algorithm that typically requires a distinct training set. The "training" in this context would likely refer to method development and optimization, for which specific sample sizes might not be explicitly documented in a 510(k) summary focused on substantial equivalence.
9. How the Ground Truth for the Training Set Was Established
As noted above, this information is not available as the context for a "training set" in an AI/ML sense is not relevant here. For the development and optimization of the enzymatic assay, the "ground truth" would be established through a combination of chemical principles, known substrate/product concentrations, and potentially comparison with established methods during the R&D phase.
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510(k) Summary
Introduction
According to the requirements of 21 CFR 807.92, the following provides sufficient detail to understand the basis for a determination of substantial equivalence.
Submitter, name, address, contact
Roche Diagnostics 9115 Hague Road PO Box 50416 Indianapolis, IN 46250 Phone: 317-521-3380 Fax: 317-521-2324
Contact person: Susan Hollandbeck Email: Susan.Hollandbeck@roche.com (317) 521-2324 Fax:
Date prepared: June 1, 2012 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Device name
Proprietary name: Homocysteine Enzymatic Assay Common name: Homocysteine test system Classification name: Urinary homocystine (nonquantitative) test system under 21 CFR 862.1377 Product code: LPS
Calibrator: Proprietary name: Homocysteine Calibrator Kit Common name: Calibrator Classification name: 21 CFR 862.1150 Product code: JIX
Control:
Assay:
Proprietary name: Homocysteine Control Kit Common name: Quality control material (assayed and unassayed) Classification name: 21 CFR 862.1660 Product code: JJX
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510(k) Summary, Continued
Device description
Assay:
The Homocysteine Enzymatic Assay is based on an enzyme cycling assay principle that assesses the co-substrate conversion product. In this assay, oxidized homocysteine (Hcy) is first reduced to free Hcy which then reacts with a co-substrate, S-adenosylmethionine, to form methionine and S-adenosylhomocysteine (SAH), catalyzed by a Hcy Smethyltransferase. SAH is assessed by coupled enzyme reactions where SAH is hydrolyzed into adenosine (Ado) and Hcy by SAH hydrolase, and Hcy is cycled into the Hcy conversion reaction to form a reaction cycle that amplifies the detection signal. The formed Ado is immediately hydrolyzed into inosine and ammonia which reacts with glutamate dehydrogenase with concomitant conversions of NADH to NAD*. The concentration of Hcy in the sample is indirectly proportional to the amount of NADH converted to NAD which is measured spectrophotometrically at 340 nm.
Calibrator:
The Homocysteine Calibrator Kit is a liquid, ready-for-use calibrator based on human serum. It is a single level calibrator with lot specific values and diluted on board the analyzer to create a 5-point calibration curve.
Control:
The Homocysteine Control Kit consists of two ready-for-use controls based on human serum. The adjusted concentrations of the control components are in the low range for Control 1 and in the elevated range for Control 2.
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510(k) Summary, Continued
Intended use
Assav:
The Homocysteine Enzymatic Assay is an in vitro test for the quantitative determination of total L-homocysteine in human serum and plasma on Roche/Hitachi cobas c systems. The assay can assist in the diagnosis of patients suspected of having hyperhomocysteinemia or homocystinuria.
Calibrator:
The Homocysteine Calibrator Kit is intended for use in the calibration of quantitative Roche methods on Roche clinical chemistry analyzers as specified in the value sheets.
Control:
The Homocysteine Control Kit is intended for use in quality control by monitoring accuracy and precision for the quantitative methods as specified in the value sheets.
Predicate devices
Roche claims substantial equivalence for the Homocysteine Enzymatic Reagent to the currently marketed Diazyme Homocysteine Enzymatic Assay cleared in K061296 and K042448.
Roche claims substantial equivalence for the Homocysteine Calibrator and Controls to the currently marketed Diazyme Homocysteine Calibrator and Controls cleared in K071971 and K042448, respectively.
Substantial equivalence -Reagent
The following table compares the features of the draft device with the predicate device for the reagent.
Continued on next page
Confidential
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510(k) Summary, Continued
Substantial equivalence - Reagent (continued)
| Feature | Predicate Device:Diazyme HomocysteineEnzymatic Assay (K061296) | Draft Device:HomocysteineEnzymatic Assay |
|---|---|---|
| Intended Use | Assay is intended for the in vitroquantitative determination oftotal L-homocysteine in humanserum or plasma.The reagents can assist in thediagnosis and treatment ofpatients suspected of havinghyperhomocysteinemia andhomocystinuria. | In vitro test for the quantitativedetermination of L-homocysteine in human serumand plasma on Roche/Hitachicobas c systems.The assay can assist in thediagnosis of patients suspectedof havinghyperhomocysteinemia orhomocystinuria. |
| Sample Types | Serum, Lithium Heparin, andEDTA | Serum, Lithium Heparin,K2EDTA, and K3EDTA |
| InstrumentPlatform | COBAS INTEGRA 400 | cobas c 501 |
| Calibrator | Homocysteine Calibrator;single level, diluted to forma 5-point calibration | same |
| CalibrationFrequency | Each lot + interval (168 hours) | Every 7 days,after reagent lot change,and as required following qualitycontrol procedures |
| Calibration Mode | Logit/log5 | RCM |
| Controls | Homocysteine Controls | same |
Continued on next page
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510(k) Summary, Continued
Substantial equivalence - Reagent (continued)
| Feature | Predicate Device:Diazyme HomocysteineEnzymatic Assay (K061296) | Draft Device:HomocysteineEnzymatic Assay |
|---|---|---|
| Reagent ActiveIngredients | R1: S-adenosylmethionine,TCEP, 2-oxoglutarate, NADH | same |
| R2: homocysteine S-methyltransferase, glutamatedehydrogenase, casein (bovine) | ||
| R3: adenosine deaminase(bovine), S-adenosyl-homocysteine hydrolase, casein(bovine) | ||
| Reagent Stability | Unopened:2-8 °C until expiration date | Unopened:2-8 °C until expiration date |
| On-board in use:60 days | On-board in use:4 weeks | |
| Measuring Range | 2.8 – 50 µmol/L | 3 – 50 µmol/L |
| Lower Limits ofMeasure | LDL = 2.8 µmol/L | LoB = 3 µmol/LLoD = 3 µmol/L |
Continued on next page
. . . . .
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.
510(k) Summary, Continued
:
Substantial equivalence - Reagent (continued)
.
| Feature | Predicate Device:Diazyme HomocysteineEnzymatic Assay (K061296) | Draft Device:HomocysteineEnzymatic Assay | ||||||
|---|---|---|---|---|---|---|---|---|
| Value | CVWithinRun | CVTotalPrecision | MeanValue | CVRepeat-ability | CVInter-mediatePrecision | |||
| Precision | Hcy LowControl | $7.0 \mu M$ | 2.6% | 2.7% | HcyControl 1 | $12.2 \mu mol/L$ | 1.5% | 2.1% |
| Hcy HighControl | $29.0 \mu M$ | 2.3% | 3.4% | HcyControl 2 | $39.1 \mu mol/L$ | 1.8% | 2.0% | |
| Humanserum 1 | $11.0 \mu M$ | 2.5% | 3.6% | Humanserum 1 | $8.26 \mu mol/L$ | 2.0% | 2.3% | |
| Humanserum 2 | $15.6 \mu M$ | 1.9% | 2.4% | Humanserum 2 | $13.1 \mu mol/L$ | 1.8% | 2.1% | |
| Humanserum 3 | $30.0 \mu mol/L$ | 1.4% | 1.8% | |||||
| Humanserum 4 | $44.4 \mu mol/L$ | 2.0% | 2.2% | |||||
| Expected Values | US: 15 μmol/L is used as thecut-off value for normal levels ofhomocysteine in adults. | same | ||||||
| Europe: 12 μmol/L is used as thecut-off value for normal levels ofhomocysteine in adults. |
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510(k) Summary, Continued
Substantial equivalence - Reagent (continued)
| Feature | Predicate Device: | Draft Device: |
|---|---|---|
| Diazyme Homocysteine | Homocysteine | |
| Enzymatic Assay (K061296) | Enzymatic Assay | |
| Interferences | Patients who are takingmethotrexate, carbamazepine,phenytoin, nitrous oxide,anticonvulsants, or 6-azuridinetriacetate, may have higherlevels of Hcy due to metabolicinterference with Hcymetabolism | NOTE: Patients who are takingmethotrexate, carbamazepine,phenytoin, nitrous oxide,anticonvulsants, or 6-azuridinetriacetate may have higher levelsof Hcy due to metabolicinterference with Hcymetabolism. |
| S-Adenosylhomocysteine (SAH)will cause a significant positiveinterference. However, SAH isonly detectable at sub-nmol/Lconcentrations in normal plasma,and should not cause concern. | ||
| Icterus:No significant interference | ||
| Hemolysis:No significant interference up toan H index of 100 | ||
| Hemolysis:No significant interference | ||
| Lipemia:No significant interference | Lipemia:No significant interference up toan L index of 250 | |
| Triglycerides:No significant interference up to1790 mg/dl. | ||
| Drugs:No interference was found attherapeutic concentrations usingcommon drug panels. | ||
| Feature | Predicate Device:Diazyme HomocysteineEnzymatic Assay (K061296) | Draft Device:HomocysteineEnzymatic Assay |
| Interferences,continued | Other:The following substancesnormally present in the serumproduced less than 10%deviation when tested at thestated concentrations: 500 μMNH4Cl, 1 mM NaPi, 1 mM NaF,0.5 mM Glutathione, 10 mMAscorbic Acid, 1 mM L-Cysteine, 20 μM S-Adenosylmethionine (SAM),100 μM Adenosine, 100 μMCystathionine | Additional drugs tested includeGlutathione at 0.5 mmol/L,Cystathionine at 100 μmol/L,and Pyruvate at 0.5 mmol/L; nointerference was found. |
| Addition of 3-deazaadenosine toinhibit Hcy production in redcells has been suggested.However, the HomocysteineEnzymatic Assay can not usesamples containing 3-deazaadenosine since it inhibitsone of the key enzymes used inthe assay. | Addition of 3-deazaadenosine toinhibit Hcy production in redcells has been suggested.However, the HomocysteineEnzymatic Assay can not usesamples containing 3-deazaadenosine since it inhibitsone of the key enzymes used inthe assay.In very rare cases, gammopathy,in particular IgM(Waldenstrom'smacroglobulinemia), may causeunreliable results. |
Continued on next page
Confidential
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510(k) Summary, Continued
Substantial equivalence - Reagent (continued)
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510(k) Summary, Continued
The following table compares the features of the draft device with the Substantial equivalence predicate device for the calibrator. Calibrator
| Feature | Predicate Device:Diazyme HomocysteineCalibrator (K071971) | Draft Device:Homocysteine Calibrator |
|---|---|---|
| Intended Use | The Diazyme HomocysteineCalibrator is intended for use inthe calibration of quantitativedetermination of Homocysteinewith the Diazyme HomocysteineEnzymatic methods on COBASINTEGRA, cobas c, and ModularP analyzers. | The Homocysteine Calibrator Kitis intended for use in thecalibration of quantitative Rochemethods on Roche clinicalchemistry analyzers as specified inthe value sheets. |
| Analyte | Homocysteine | Same |
| Matrix | Human serum | Same |
| Storage | 2-8 °C | Same |
Substantial The following table compares the features of the draft device with the equivalencepredicate device for the control set. Control Set
| Feature | Predicate Device:Diazyme HomocysteineControls (K042448) | Draft Device:Homocysteine Control |
|---|---|---|
| Intended Use | The Diazyme HomocysteineControls are intended for use aspart of a quality assurance systemfor the Diazyme HomocysteineEnzymatic Assay | The Homocysteine Control Kit isintended for use in quality controlby monitoring accuracy andprecision for the quantitativemethods as specified in the valuesheets. |
| Analyte | Homocysteine | Same |
| Matrix | 2 - level set with a normalserum homocysteine level andan abnormal homocysteine level | Same |
| Storage | 2-8 °C | Same |
. '
End of Summary
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DEPARTMENT OF HEALTH & HUMAN SERVICES
Image /page/9/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 perimeter. Inside the circle, there is a stylized image of an eagle with its wings spread.
10903 New Hampshire Avenue Silver Spring, MD 20993
Roche Diagnostics c/o Susan Hollandbeck 9115 Hague Road P. O. Box 50416 Indianapolis, IN 46250
JUN - 5 2012
Re: K113793
Trade Name: Homocysteine Enzymatic Assay; Homocysteine Calibrator Kit, Homocysteine Control Kit
Regulation Number: 21 CFR §862.1377
Regulation Name: Urinary Homocysteine (non quantitative) test system Regulatory Class: Class II Product Codes: LPS, JIX, JJX Dated: May 23, 2012 Received: May 24, 2012
Dear Ms. Hollandbeck:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and 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) that do not require approval of a premarket approval application (PMA). 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 (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR), Parts 800 to 895. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820).
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Page 2
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please If you desire specific ad view sor your stic Device Evaluation and Safety at (301) 796-5450. Also, comation of the regulation entitled, "Misbranding by reference to premarket notification" (2) proase note increading onlined, "Miser news of entreallance, please contact CDRH's Office of Surveillance and Biometric's (OSB's) Division of Postmarket Surveillance at (301) Office of Surveinance and Drolliers of Solication of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/Medical
CI K Far 805), predsogo to maplefault.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance...
You may obtain other general information on your responsibilities under the Act from the Tou may of amall Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-5680 or at its Internet address http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.html
Sincerely yours,
V.
Steven H. Lipton, Ph.D.
Courney H. Lias, Ph.D. Director Division of Chemistry and Toxicology Devices Office of In Vitro Diagnostic Device Evaluation and Safety Center for Devices and Radiological Health
Enclosure
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Indications for Use
510(k) Number (if known):
KIL3793
Device Name: Homocysteine Enzymatic Assay; Homocysteine Calibrator Kit; and Homocysteine Control Kit
Indications For Use:
The Homocysteine Enzymatic Assay is an in vitro test for the quantitative determination of total L-homocysteine in human serum and plasma on Roche/Hitachi cobas c systems. The assay can assist in the diagnosis of patients suspected of having hyperhomocysteinemia or homocystinuria.
The Homocysteine Calibrator Kit is intended for use in the calibration of quantitative Roche methods on Roche clinical chemistry analyzers as specified in the value sheets.
The Homocysteine Control Kit is intended for use in quality control by monitoring accuracy and precision for the quantitative methods as specified in the value sheets.
Prescription Use (Part 21 CFR 801 Subpart D) AND/OR
Over-The-Counter Use (21 CFR 801 Subpart,C)
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED) .
oncurrence of CDRH, Office of In Vitro Diagnostic Devices (OIVD)
Division Sign-Off Office of In Vitro Diagnostic Device Evaluation and Safety
510(k) K113793
Page 1 of ﺴﻤﺴﺮ
§ 862.1377 Urinary homocystine (nonquantitative) test system.
(a)
Identification. A urinary homocystine (nonquantitative) test system is a device intended to identify homocystine (an analogue of the amino acid cystine) in urine. The identification of urinary homocystine is used in the diagnosis and treatment of homocystinuria (homosystine in urine), a heritable metabolic disorder which may cause mental retardation.(b)
Classification. Class II.