Pointe Scientific Creatinine Kinase (CK) Reagent Set

K191296 · Medtest DX · CGS · Aug 11, 2020 · Clinical Chemistry

Device Facts

• Record ID: K191296
• Device Name: Pointe Scientific Creatinine Kinase (CK) Reagent Set
• Applicant: Medtest DX
• Product Code: CGS · Clinical Chemistry
• Decision Date: Aug 11, 2020
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 862.1215
• Device Class: Class 2

Intended Use

For the quantitative determination of creatine kinase activity in serum and plasma. Rx Only. Measurements of Creatine Kinase are used in the diagnosis and treatment of myocardial infarction and muscle disease, such as progressive Duchenne-type muscular dystrophy.

Device Story

Pointe Scientific Creatine Kinase (CK) Reagent Set is an in vitro diagnostic, quantitative enzymatic colorimetric assay. It utilizes liquid reagents (CK R1 and R2) to catalyze the transphosphorylation of ADP to ATP, resulting in NADPH production at a rate proportional to CK activity. The device is designed for use on the Mindray BA-800M chemistry analyzer. The system measures NADPH absorbance increase per minute at 340 nm. Healthcare providers use the resulting CK activity levels to assist in the diagnosis and management of myocardial infarction and muscle disorders. The assay is intended for professional use in clinical laboratory settings.

Clinical Evidence

Bench testing only. Performance validated via precision (CLSI EP05-A3), linearity (CLSI EP06-A), interference (CLSI EP07-A3), and detection limits (CLSI EP17-A2). Method comparison studies (n=120 serum, n=123 plasma) against the predicate device showed strong correlation (Deming regression: Y=1.041X-5.2, r=0.9991 for serum; Y=1.032X-0.4, r=0.9946 for plasma).

Technological Characteristics

Quantitative enzymatic colorimetric assay. Reagents: Imidazole buffer, NADP, HK, Glucose, Magnesium Acetate, EDTA, N-acetylcysteine, ADP, AMP, Diadensosine pentaphosphate, Creatine phosphate, G6PDH. Measuring range: 9-1200 U/L. Traceable to IFCC reference method. Requires Mindray BA-800M chemistry analyzer. Standards: CLSI EP05-A3, EP06-A, EP07-A3, EP17-A2, EP34.

Indications for Use

Indicated for quantitative determination of creatine kinase activity in serum and plasma for patients requiring diagnosis or treatment of myocardial infarction or muscle diseases, such as progressive Duchenne-type muscular dystrophy.

Regulatory Classification

Identification

A creatine phosphokinase/creatine kinase or isoenzymes test system is a device intended to measure the activity of the enzyme creatine phosphokinase or its isoenzymes (a group of enzymes with similar biological activity) in plasma and serum. Measurements of creatine phosphokinase and its isoenzymes are used in the diagnosis and treatment of myocardial infarction and muscle diseases such as progressive, Duchenne-type muscular dystrophy.

Predicate Devices

• Olympus Creatine Kinase Reagent (K043202)

Submission Summary (Full Text)

{0}------------------------------------------------

August 11, 2020

MedTest Dx William Cripps Director, R&D, QA/RA 5449 Research Drive Canton, MI 48188

Re: K191296

Trade/Device Name: Pointe Scientific Creatine Kinase (CK) Reagent Set Regulation Number: 21 CFR 862.1215 Regulation Name: Creatine phosphokinase/creatine kinase or isoenzymes test system Regulatory Class: Class II Product Code: CGS Dated: July 8, 2020 Received: July 10, 2020

Dear William Cripps:

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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. 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 Part

{1}------------------------------------------------

801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.

For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email ([e-mail]) or phone [phone] or 301-796-7100).

Sincerely,

Marianela Perez-Torres, Ph.D. Acting Deputy Director Division of Chemistry and Toxicology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health

Enclosure

{2}------------------------------------------------

DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration

Indications for Use

Form Approved: OMB No. 0910-0120 Expiration Date: 06/30/2020 See PRA Statement below.

510(k) Number (if known) K191296

Device Name

Pointe Scientific Creatine Kinase (CK) Reagent Set

#### Indications for Use (Describe)

For the quantitative determination of creatine kinase activity in serum and plasma. Rx only.

Measurements of Creatine Kinase are used in the diagnosis and treatment of myocardial infaction and muscle disease, such as progressive Duchenne-type muscular dystrophy.

Type of Use (Select one or both, as applicable)

> Prescription Use (Part 21 CFR 801 Subpart D)

Over-The-Counter Use (21 CFR 801 Subpart C)

#### CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

#### *DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.*

The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

> Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff [e-mail]

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

FORM FDA 3881 (7/17)

Page 1 of 1

PSC Paklishing Survices [phone] EF

{3}------------------------------------------------

# 5. 510(k) SUMMARY (k191296)

This 510(k) Summary of Safety and Effectiveness is being submitted in accordance with the requirements of Safe Medical Device Act of 1990 and 21 CFR 807.92.

#### a. Device Information

| Category | Comments |
|----------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------|
| Sponsor | MedTest Dx<br>5449 Research Drive<br>Canton, MI 48188<br>Phone: [phone]<br>Fax: [phone] |
| Correspondent<br>Contact Information | William Cripps<br>Director, R&D/RA/QA<br>Email: [e-mail]<br>Phone: [phone] ext. 120<br>Fax: [phone] |
| Device Common<br>Name | Creatine Kinase (CK) |
| Trade or Proprietary<br>Name | Pointe Scientific Creatine Kinase (CK) Reagent Set |
| Candidate Device<br>Product Code,<br>Classification,<br>Classification Name<br>& Panel | CGS, Class II, 21 CFR 862.1215 - Nad Reduction/Nadh<br>Oxidation, Cpk Or Isoenzymes, 75 – Clinical Chemistry |

#### Predicate Device Information

| Predicate Device | Olympus Creatine Kinase<br>Reagent |
|--------------------------------------------------|------------------------------------|
| Predicate Device<br>Manufacturer | Beckman Coulter, Inc. |
| Predicate Device<br>Premarket<br>Notification #: | K043202 |

#### b. Date Summary Prepared

May 10, 2019 Updated on: October 4, 2019 Updated on: November 8, 2019 Updated on: July 8, 2020 Updated on: August 4, 2020

{4}------------------------------------------------

### c. Description of Device

The Pointe Scientific Creatine Kinase (CK) Reagent Set consists of ready-to-use liguid reagents:

- . CK R1 (buffer) contains: Imidazole buffer (pH 6.7) 100.0 mmol/L; NADP 2.0 mmol/L: HK (Baker's yeast) 2.5 KU/L: Glucose 20.0 mmol/L: Magnesium Acetate 10.0 mmol/L; EDTA 2.0 mmol/L and N-acetylcysteine (NAC) 20.0 mmol/L.
- . CK R2 (enzyme reagent) contains: Imidazole buffer (pH 6.7) 100.0 mmol/L: ADP 2.0 mmol/L: AMP 5.0 mmol/L: Diadensosine pentaphosphate 10.0 mmol/L: Creatine phosphate 30.0 mmol/L; G6PDH (Baker's yeast) 1.5 KU/L and EDTA 2.0 mmol/L.

The kinetic procedure presented is a modification of Szasz of the Rosalki technique, which optimizes the reaction by reactivation of CK activity with N-actyl-L-cysteine (NAC).

Creatine Kinase specifically catalyzes the transphosphorylation of ADP to ATP. Through a series of coupled enzymatic reactions, NADPH is produced at a rate directly proportional to the CK activity. The method determines the NADPH absorbance increase per min at 340 nm.

#### d. Intended Use

For the quantitative determination of creatine kinase activity in serum and plasma. Rx Only.

Measurements of Creatine Kinase are used in the diagnosis and treatment of myocardial infarction and muscle disease, such as progressive Duchenne-type muscular dystrophy.

{5}------------------------------------------------

# e. Comparison to Predicate Device

The chart below illustrates the similarities between the Pointe Scientific Creatine Kinase (CK) Reagent Set and the predicate, Beckman Coulter Creatine Kinase.

| Characteristics | Pointe Scientific Creatine<br>Kinase (CK) Reagent Set<br>(Proposed Device) | Beckman Coulter K043202<br>(Predicate Device) |
|----------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Intended Use | For the quantitative<br>determination of creatine kinase<br>activity in serum and plasma. Rx<br>Only.<br>Measurements of Creatine<br>Kinase are used in the diagnosis<br>and treatment of myocardial<br>infarction and muscle disease,<br>such as progressive Duchenne-<br>type muscular dystrophy. | For use in the Olympus<br>automated clinical chemistry<br>analyzers for the quantitative<br>determination of creatine<br>kinase activity in human<br>serum and plasma<br>Measurements of Creatine<br>Kinase are used in the<br>diagnosis and treatment of<br>myocardial infarction and<br>muscle disease, such as<br>progressive Duchenne-type<br>muscular dystrophy. |
| Contents | • CK R1 (buffer) contains:<br>Imidazole buffer (pH 6.7) 100.0<br>mmol/L; NADP 2.0 mmol/L; HK<br>(Baker's yeast) 2.5 KU/L;<br>Glucose 20.0 mmol/L;<br>Magnesium Acetate 10.0<br>mmol/L; EDTA 2.0 mmol/L and<br>N-acetylcysteine (NAC) 20.0<br>mmol/L.<br>• CK R2 (enzyme reagent)<br>contains: Imidazole buffer (pH<br>6.7) 100.0 mmol/L; ADP 2.0<br>mmol/L; AMP 5.0 mmol/L;<br>Diadensosine pentaphosphate<br>10.0 mmol/L;<br>Creatine<br>phosphate 30.0 mmol/L;<br>G6PDH (Baker's yeast) 1.5<br>KU/L and EDTA 2.0 mmol/L. | • Final concentration of<br>reactive ingredients:<br>• Imidazole (pH 6.5) 100<br>mmol/L<br>• HK (Yeast) ≥ 4.0 kU/L (66.7<br>µkat/L)<br>• NADP 2 mmol/L<br>• G6P-DH (Leuconostoc<br>mesenteroides) ≥ 2.8 kU/L<br>(46.7 µkat/L)<br>• ADP 2 mmol/L<br>• Mg2+ 20 mmol/L<br>• AMP 5 mmol/L<br>• Diadenosine<br>pentaphosphate 10 µmol/L<br>• EDTA 2 mmol/L<br>• Glucose 20 mmol/L<br>• Creatine Phosphate 30<br>mmol/L<br>• N-Acetylcysteine 0.2 mmol/L<br>• Stabilizers<br>• Also contains preservatives |
| | | |
| Principle | The kinetic procedure presented<br>is a modification of Szasz of the<br>Rosalki technique, which<br>optimizes the reaction by<br>reactivation of CK activity with<br>N-actyl-L-cysteine (NAC).<br><br>CK specifically catalyzes the<br>transphosphorylation of ADP to<br>ATP. Through a series of<br>coupled enzymatic reactions,<br>NADPH is produced at a rate<br>directly proportional to the CK<br>activity. The method determines<br>the NADPH absorbance<br>increase per min at 340 nm. | This CK procedure is a<br>modification of the IFCC<br>method. CK reversibly<br>catalyzes the transfer of a<br>phosphate group from<br>creatine phosphate to<br>adenosine diphosphate (ADP)<br>to give creatine and<br>adenosine triphosphate (ATP)<br>as products. The ATP formed<br>is used to produce glucose-6-<br>phosphate and ADP from<br>glucose. This reaction is<br>catalyzed by hexokinase (HK)<br>which requires magnesium<br>ions for maximum activity.<br>The glucose6-phosphate is<br>oxidized by the action of the<br>enzyme glucose-6-phosphate<br>dehydrogenase (G6P-DH)<br>with simultaneous reduction<br>of the coenzyme<br>nicotinamide adenine<br>dinucleotide (NADP) to give<br>NADPH and 6-<br>phosphogluconate. The rate<br>of increase of absorbance at<br>340/660 nm due to the<br>formation of NADPH is<br>directly proportional to the<br>activity of CK in the sample |
| Sample Type | Serum and lithium heparin<br>plasma | Serum and heparinized<br>plasma |
| Measurement<br>Range | 9-1200 U/L | 10-2000 U/L |

{6}------------------------------------------------

{7}------------------------------------------------

### Performance Data

All analytical performance studies presented below were performed on the Shenzhen Mindrav BA-800M Chemistry Analyzer. All studies were performed using either serum samples collected in serum separator tubes (SST) or plasma collected in lithium heparin tubes.

### Method Comparison Study

Two separate split-sample method comparison studies between the Pointe Scientific Creatine Kinase (CK) Reagent Set on the Shenzhen Mindray BA-800M Chemistry Analyzer versus the predicate Beckman Coulter Creatine Kinase (CK-Nac) on the Beckman Coulter Olympus AU400 Clinical Chemistry Analyzer were performed on either serum or plasma samples following CLSI EP09-A2 guidelines using one lot of each of the manufacturer's reagents and a single BA-800M Chemistry analyzer and a single AU400 Clinical Chemistry Analyzer.

## a. Method Comparison with serum:

A total of 120 deidentified remnant serum samples were obtained from a commercial repository and tested in duplicate across the assay range of 9-1188 U/L. Of these samples, 4 were altered by mixing of two samples together to obtain an analyte level within the measurement range. Samples were analyzed in singlicate. Results using a Deming regression were obtained with EP Evaluator Software. Results from single representative data set are summarized below:

| Serum-Serum | |
|-------------------------|------------------|
| Method | Creatine Kinase |
| N | 120 |
| Range (U/L) | 9-1188 |
| Standard Deviation | 249.5 |
| Regression Analysis | y = 1.041x - 5.2 |
| Correlation Coefficient | 0.9991 |

# b. Method Comparison with plasma:

A total of 123 deidentified remnant Plasma samples were obtained from a commercial repository and tested in duplicate across the assay range of 9-1119 U/L. Of these samples, 2 were altered by mixing of two samples together to obtain an analyte level within the measurement range. Samples were analyzed in singlicate. Results using a Deming regression were obtained with EP Evaluator Software. Results from single representative data set are summarized below:

| Plasma-Plasma | |
|-------------------------|--------------------|
| Method | Creatine Kinase |
| N | 123 |
| Range (U/L) | 9-1119 |
| Standard Deviation | 255.4 |
| Regression Analysis | $y = 1.032x - 0.4$ |
| Correlation Coefficient | 0.9946 |

Plasma-Plasma

{8}------------------------------------------------

#### Precision Studies

Precision studies were conducted in accordance with CLSI EP05-A3. Samples consisted of two commercial quality controls, three serum pools and three plasma pools. Analyte levels of the tested pools approximated Westgard medical decision points for normal and elevated creatine kinase levels. A third level for each matrix was included above the mid-point of the measurable range for each matrix.

Testing was performed utilizing two lots of the Pointe Scientific Creatine Kinase (CK) Reagent Set on the same Shenzhen Mindray BA-800M Chemistry Analyzer. Pools were tested in duplicate twice per day for a total of 20 days (final n per sample = 80). Results from a single representative lot are summarized below.

| Matrix | Sample | N | Mean CK | Repeatability | | Total | |
|----------|-----------|----|---------|---------------|-----|-------|-----|
| | | | (U/L) | SD | %CV | SD | %CV |
| Controls | Control 1 | 80 | 134.37 | 1.22 | 0.9 | 1.97 | 1.5 |
| Controls | Control 2 | 80 | 265.18 | 1.35 | 0.5 | 4.39 | 1.7 |
| Serum | Level 1 | 80 | 88.19 | 1.50 | 1.7 | 3.16 | 3.6 |
| Serum | Level 2 | 80 | 288.02 | 1.79 | 0.8 | 8.71 | 3.8 |
| Serum | Level 3 | 80 | 691.63 | 3.20 | 0.5 | 10.40 | 1.5 |
| Plasma | Level 1 | 80 | 109.18 | 1.12 | 1.0 | 3.83 | 3.5 |
| Plasma | Level 2 | 80 | 219.33 | 1.36 | 0.6 | 5.05 | 2.3 |
| Plasma | Level 3 | 80 | 686.11 | 5.79 | 0.8 | 13.86 | 2.0 |

## Linearity/Assay Range Study

A linearity study was conducted according to CLSI EP06-A. A set of 12 serum samples ranging from 9 to 1700 U/L or 12 plasma samples ranging from 8 to 1595 U/L were prepared by admixture of high-level and low-level sample pools. Each admixture was analyzed in duplicate using two lots of reagent on the same Shenzhen Mindray BA-800M Chemistry Analyzer.

The results from one representative lot run are summarized below. Acceptable deviation from expected value was set at less than or equal to 10%. The linearity study data supports the claimed range of 9 to 1200 U/L.

| Matrix: Serum | | | | Matrix: Plasma | | | |
|---------------|----------------|--------------------|---------------|----------------|----------------|--------------------|---------------|
| Sample | Mean<br>Result | Expected<br>Result | %<br>Recovery | Sample | Mean<br>Result | Expected<br>Result | %<br>Recovery |
| Low | 9 | 9 | 100% | Low | 8 | 8 | 100% |
| Dil 1 | 96 | 94 | 102% | Dil 1 | 88 | 87 | 102% |
| Dil 2 | 145 | 145 | 100% | Dil 2 | 133 | 135 | 99% |
| Dil 3 | 222 | 221 | 100% | Dil 3 | 196 | 206 | 95% |
| Dil 4 | 252 | 263 | 96% | Dil 4 | 227 | 246 | 93% |
| Dil 5 | 423 | 432 | 98% | Dil 5 | 372 | 404 | 92% |
| Dil 6 | 645 | 643 | 100% | Dil 6 | 595 | 603 | 99% |
| Dil 7 | 855 | 855 | 100% | Dil 7 | 801 | 801 | 100% |
| Dil 8 | 1060 | 1066 | 99% | Dil 8 | 1024 | 999 | 102% |
| Dil 9 | 1254 | 1277 | 98% | Dil 9 | 1206 | 1198 | 101% |
| Dil 10 | 1448 | 1489 | 97% | Dil 10 | 1455 | 1396 | 104% |
| High | 1637 | 1700 | 96% | High | 1669 | 1595 | 105% |

{9}------------------------------------------------

#### Detection Capability

The limit of blank (LoB), limit of detection (LoD), and limit of quantitation (LoQ) were determined for both serum and plasma in accordance to CLSI EP17-A2 suggested quidelines on two lots of Pointe Creatine Kinase (CK) Reagent Sets and a single BA-800M Chemistry Analyzer.

Saline was used as the blank sample for the determination of LoB. Sixty measurements (1 sample X 20 repetitions x 3 days each) were analyzed across two lots of reagent to determine the LoB of the system. Using a non-parametric distribution calculation of LoB, as detailed in CLSI EP17-A2, the limit of blank was determined to be 2 U/L.

For LoD determination, twenty low-level depleted serum samples and twenty depleted plasma samples were analyzed in duplicate across two lots of reagent within a single day. Results were used in conjunction with Limit of Blank results to determine LoD using the equation LoD=LoB +1.625(SDLow Level Samples), per CLSI 17-A2 quidance. Results from one representative lot are presented below.

The LoQ is the lowest amount of creatine kinase that can be determined quantitatively within a defined precision (<20% CV). A series of 5 low activity samples were each run in 8 duplicates over a range of 5 days. Data analysis was performed by EP Evaluator statistical software. The LoQ value was derived from the lowest sample results exhibiting a precision CV of less than 20%.

| | Creatine Kinase (U/L) | | |
|-----------------------|-----------------------|-------|--|
| | Plasma | Serum | |
| Limit of Blank | 2 | 2 | |
| Limit of Detection | ব | ব | |
| Limit of Quantitation | ರ | ರ | |

{10}------------------------------------------------

# Dilution Recovery Studies

Studies were performed to provide evidence that values of highly concentrated samples of creatine kinase outside of the claimed measurement range (9-1200 U/L) can be accurately determined through a 10-fold dilution of the sample (as prescribed in the instruction for use). A dilution recovery study was undertaken utilizing suggested methods from CLSI EP34-E1. Three contrived high-level samples greater than the Pointe Creatine Kinase (CK) Reagent Set's measurement range for both serum and plasma were diluted in physiological saline at dilutions of 1:2; 1:4; 1;10 and 1:12 then subsequently analyzed using two lots of the Pointe Creatine Kinase (CK) Reagent set on the same Shenzhen Mindray BA-800M Chemistry. Results from one representative reagent lot for each matrix type are presented below.

| Dilution Factor | Mean<br>(U/L, dilute) | Theoretical<br>Result (U/L) | Calculated Result<br>(U/L) | % recovery |
|-----------------|-----------------------|-----------------------------|----------------------------|------------|
| Matrix: Serum | | | | |
| 1:2 | 1664.5 | 3686 | 3329 | 90 |
| 1:4 | 903 | 3686 | 3612 | 98 |
| 1:10 | 380 | 3686 | 3800 | 103 |
| 1:12 | 322.5 | 3686 | 3870 | 105 |
| Matrix: Plasma | | | | |
| 1:2 | 1608 | 3064 | 3216 | 105 |
| 1:4 | 832 | 3064 | 3328 | 109 |
| 1:10 | 328.5 | 3064 | 3285 | 107 |
| 1:12 | 266 | 3064 | 3192 | 104 |

# Analytical Specificity (Endogenous Substances)

Interference studies were performed following the recommendation of CLSI EP07-A3. Interference testing was conducted using one lot of reagent and one Mindray BA-800M analyzer. All interferents were evaluated in randomly selected serum and plasma samples ranging from 43 U/L to 268 U/L. Interferents were tested across an evenly spaced range of concentrations. The range of interferent concentrations were derived through admixtures of high and low interferent concentration pools. Significant interference was defined by the sponsor as a percent difference greater than 10% from control.

| Interferent | Highest Concentration at which no<br>significant interference was observed |
|--------------------------------------------|----------------------------------------------------------------------------|
| Bilirubin (Conjugated and<br>Unconjugated) | 60 mg/dL |
| Ascorbic Acid | 500 mg/dL |
| Hemoglobin | 500 mg/dL |
| Intralipid | 1382 mg/dL |

{11}------------------------------------------------

#### Traceability, Stability, Expected values

Traceability: The Pointe Scientific Creatine Kinase (CK) Assay is traceable to the IFCC reference method.

Stability: The reagent shelf life stability claim is 24 months at 2-8°C. The reagent onboard (in use and refrigerated) stability claim is 29 days.

Expected Values: This information is the same as for the predicate device (k043202). The expected values in an adult population (from 200 blood donors in North Texas) are 30-223 U/L creatine kinase.

Conclusion: Based on the results of the testing conducted, the Pointe Scientific Creatine Kinase (CK) Reagent Set is substantially equivalent to the predicate device, the Olympus Creatine Kinase Reagent (K043202).