(25 days)
No
The device description and performance studies focus on standard laboratory assay components and analytical performance metrics, with no mention of AI/ML algorithms or data processing techniques.
No
The device is described as an "in vitro measurement of IgA" used to "aid in the diagnosis of abnormal protein metabolism and the body's lack of ability to resist infectious agents," which classifies it as a diagnostic tool, not a therapeutic device.
Yes
The "Intended Use / Indications for Use" section explicitly states that "Measurement of IgA aids in the diagnosis of abnormal protein metabolism and the body's lack of ability to resist infectious agents." This clearly indicates its role in disease diagnosis.
No
The device description clearly states it comprises reagents (Antiserum, Calibrator and Controls, Reaction Buffer), which are physical components, not software.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The "Intended Use / Indications for Use" section explicitly states that the kit is for the "quantitative in vitro measurement of IgA in serum, lithium heparin or EDTA plasma". The term "in vitro" is a key indicator of an IVD.
- Device Description: The description details reagents used to perform a test on biological samples (serum, plasma) outside of the body.
- Purpose: The test aids in the "diagnosis of abnormal protein metabolism and the body's lack of ability to resist infectious agents," which is a diagnostic purpose.
- Care Setting: It is indicated for "Prescription use only," which is common for diagnostic tests performed in a clinical setting.
N/A
Intended Use / Indications for Use
The Optilite IgA Kit is intended for the quantitative in vitro measurement of IgA in serum, lithium heparin or EDTA plasma using the Binding Site Optilite analyser. Measurement of IgA aids in the diagnosis of abnormal protein metabolism and the body's lack of ability to resist infectious agents. This test should be used in conjunction with other laboratory and clinical findings.
Product codes
CFN, JIT, JJX
Device Description
The Optilite IgA Kit comprises the following reagents:
Antiserum: Goat anti IgA supplied in stabilised liquid form. Preservatives: 0.099% sodium azide, 0.1% E-amino-n-caproic acid (EACA), 0.5% BSA and 0.01% benzamidine.
Calibrator and Controls: Pooled human serum, supplied in stabilised liquid form. Contain 0.099% sodium azide, 0.1% EACA and 0.01% benzamidine as preservatives. The concentration given on the quality control certificate has been obtained by comparison with the DA470k international reference material.
Reaction Buffer: Containing 0.099% sodium azide as a preservative.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Prescription Use (Part 21 CFR 801 Subpart D)
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Precision/Reproducibility: A repeatability and within laboratory study was performed over 20 working days, with 2 runs per day and 2 replicates per run. 5 different samples were assessed using 1 reagent lot on 1 analyser. A between instrument precision study was performed over 6 working days, 2 instruments were tested each day with 2 replicates per instrument. 5 different samples were assessed using 1 reagent lot on 3 different analysers. A between lot precision study was performed over 6 working days, 2 lots were tested each day with 2 replicates per lot. 5 different samples were assessed using 3 reagent lots on 1 analyser. The results showed no significant change in performance compared to the predicate device.
Linearity/Assay Reportable Range: A linearity study was carried out by producing a dilution series from a high pool with a known concentration of 8.59 g/L and a low pool concentration of 0.10 g/L. Each diluted sample was tested in 3 replicates and a linear regression analysis was carried out. The linear regression equation was shown to be y=1.007x + 0.159 g/L with an R value of 0.999. These results are comparable to those currently presented in the product insert and do not indicate any change in performance.
Traceability, Stability, Expected values (controls, calibrators, or methods):
- Traceability: The calibration is traceable to ERM-DA470k/IFCC.
- Accelerated Stability: Studies were carried out to verify that the stability of the kit is unchanged in accordance with ISO 23640:2015. 6 replicates of controls, internal reference and samples were tested over a period equivalent to 19 months. Reagents were stored at 37ºC to accelerate the study by a factor of 10. The results for internal reference (IR), low/high controls, and samples 1, 2, 3 passed the stability requirements.
- Real Time Stability: A real time stability study is currently being carried out.
- On Board Stability: On-board stability studies showed no difference in the cleared on-board stability claim.
Detection Limit: The limit of quantitation (LoQ) is 0.02 g/L, validated by testing four samples using two reagent lots, with all samples reporting within the acceptance criteria of an allowable CV of 8%. The limit of detection (LoD) was estimated as 0.007 g/L, and the limit of blank (LoB) was estimated to be 0.005 g/L. No change in performance was observed after antisera change.
Analytical Specificity: As per original submission (K103824).
Method comparison with predicate device: A comparison study was performed by analysing 102 serum samples and 42 plasma samples using the modified Optilite IgA Kit and the cleared Optilite kit (K103824). Bland Altman and Passing Bablok regression analysis generated the following results: Bland Altman Mean Bias of 2.38% with 95% Limits of Agreement -10.6% to 15.37%. Passing Bablok equation y= 1.012x + 0.011 with Slope 95% CI 1.001 to 1.027 and Intercept 95% CI -0.006 to 0.044. Correlation coefficient of 0.998. These results do not indicate any change in performance.
Matrix comparison: Serum and plasma matrices were included in the method comparison study. No difference between matrices were observed.
Expected values/Reference range: 20 samples from apparently healthy US donors were tested. 19 samples gave results within the reference interval (0.947 to 4.043 g/L), and one sample was at the lower boundary (
§ 866.5510 Immunoglobulins A, G, M, D, and E immunological test system.
(a)
Identification. An immunoglobulins A, G, M, D, and E immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the immunoglobulins A, G, M, D, an E (serum antibodies) in serum. Measurement of these immunoglobulins aids in the diagnosis of abnormal protein metabolism and the body's lack of ability to resist infectious agents.(b)
Classification. Class II (performance standards).
0
Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: the Department of Health and Human Services logo on the left and the FDA logo on the right. The FDA logo is a blue square with the letters "FDA" in white, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue.
August 19, 2019
The Binding Site Group Ltd. Natasha Verhaak Regulatory Affairs Officer 8 Calthorpe Road Edgbaston, B15 10T Gb UK
Re: K191985
Trade/Device Name: Optilite IgA Kit Regulation Number: 21 CFR 866.5510 Regulation Name: Immunoglobulins A, G, M, D, And E Immunological Test System Regulatory Class: Class II Product Code: CFN, JIT, JJX Dated: July 22, 2019 Received: July 25, 2019
Dear Natasha Verhaak:
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
1
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 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 (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Douglas Jeffery, Ph.D. Chief Division of Immunology and Hematology 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) K191985
Device Name Optilite IgA Kit
Indications for Use (Describe)
The Optilite IgA Kit is intended for the quantitative in vitro measurement of IgA in serum, lithium heparin or EDTA plasma using the Binding Site Optilite analyser. Measurement of IgA aids in the diagnosis of abnormal protein metabolism and the body's lack of ability to resist infectious agents. This test should be used in conjunction with other laboratory and clinical findings.
Type of Use (Select one or both, as applicable)
X 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."
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3
Optilite IgA Kit Special 510(k) Submission Summary
Submitter Details
Natasha Verhaak Regulatory Affairs Officer The Binding Site Group Ltd. 8 Calthorpe Road Edgbaston Birmingham, West Midlands, B15 1QT, UK Telephone: +44 (0)121 456 9500 Email: natasha.verhaak@bindingsite.com or regulatory.submissions@bindingsite.com
Date Prepared: 1st August 2019
A. 510(k) Number:
B. Purpose for Submission:
Modification to an existing device
-
C. Measurand:
lgA -
D. Type of Test: Quantitative immunoturbidimetry
E. Applicant:
The Binding Site
F. Proprietary and Established Names:
Optilite IgA Kit
G. Regulatory Information:
-
- Regulation section:
21 CFR 866.5510, Immunoglobulins A, G, M, D, and E immunological test system
- Regulation section:
-
- Classification: Class II
-
- Product code: CFN - method, nephelometric, immunoglobulins (G, A, M)
-
- Panel: Immunology (82)
4
H. Intended use:
-
- Intended use(s):
The Optilite IgA Kit is intended for the quantitative in vitro measurement of IgA in serum, lithium heparin or EDTA plasma using the Binding Site Optilite analyser. Measurement of lgA aids in the diagnosis of abnormal protein metabolism and the body's lack of ability to resist infectious agents. This test should be used in conjunction with other laboratory and clinical findings.
- Intended use(s):
The intended use is the same as the cleared kit and has not been changed.
-
- Indication(s) for use:
Same as Intended use.
- Indication(s) for use:
-
- Special conditions for use statement(s):
Prescription use only
- Special conditions for use statement(s):
-
- Special instrument requirements:
The Binding Site Optilite analyser
- Special instrument requirements:
I. Device Description:
The Optilite IgA Kit comprises the following reagents:
Antiserum: Goat anti IgA supplied in stabilised liquid form. Preservatives: 0.099% sodium azide, 0.1% E-amino-n-caproic acid (EACA), 0.5% BSA and 0.01% benzamidine.
Calibrator and Controls: Pooled human serum, supplied in stabilised liquid form. Contain 0.099% sodium azide, 0.1% EACA and 0.01% benzamidine as preservatives. The concentration given on the quality control certificate has been obtained by comparison with the DA470k international reference material.
Reaction Buffer: Containing 0.099% sodium azide as a preservative.
J. Substantial equivalence information:
-
- Predicate device name(s) and 510(k) number(s):
Optilite IgA Kit (K103824)
- Predicate device name(s) and 510(k) number(s):
5
2. Comparison with predicate:
| Similarities | ||
|---|---|---|
| Item | Modified device | Registered device |
| Intended Use | Quantitative in vitro measurement of | |
| IgA | Same | |
| Test Method | Turbidimetric | Same |
| Specimen Type | Serum, lithium heparin, EDTA plasma | Same |
| Assay type | Quantitative | Same |
| On-board Stability | 30 days | Same |
| Calibration traceability | DA470k | Same |
| Measuring Range | 1+0 0.02 - 0.7 g/L | |
| 1+9 0.20 - 7.00 g/L | ||
| 1+39 0.80 - 28.00 g/L | ||
| 1+99 2.00 - 70g/L | Same | |
| Adult Reference | ||
| Interval | 0.845 - 4.990 g/L | Same |
| Instrument | Optilite | Same |
| Antigen excess | ||
| capacity | 40 g/L | Same |
| Calibration method | Pooled human sera | Same |
| Controls | Pooled human sera | Same |
| Open vial stability | 3 months | Same |
| Antibody processing | Affinity purification, specificity | |
| confirmed by IEP | Same | |
| Antibody resting buffer | GBS | Same |
| Differences | ||
|---|---|---|
| Item | Modified device | Registered device |
| Source of detection | ||
| antibody | Goat antibody | Sheep antibody |
K. Standards and Guidance documents referenced:
CLSI EP17-A2 Protocols for Determination of Limits of Detection and Limits of Quantitation; Approved Guideline
CLSI EP5-A3 Evaluation of Precision Performance of Quantitative Measurement Methods; Approved Guideline - Second Edition
CLSI EP25-A Evaluation of Stability of In Vitro Diagnostic Reagents- 1* Edition
CLSI EP6-A Evaluation of the Linearity of Quantitative Measurement Procedures
EP28-A3c Defining, Establishing, and Verifying Reference Intervals in the Clinical Laboratory, 3rd Edition
L. Test Principle:
The determination of soluble antigen concentration by turbidimetric methods involves the reaction with specific antiserum to form insoluble complexes. When light is passed through the suspension formed a portion of the light is transmitted and focused onto a photodiode by an optical lens system. The amount of transmitted light is indirectly proportional to the specific protein concentration in the test sample. Concentrations are automatically calculated by reference to a calibration curve stored within the instrument.
6
M. Performance Characteristics (if/when applicable):
-
- Analytical performance:
- Precision/Reproducibility: a.
The precision studies were based on CLSI EP5-A3 Evaluation of Precision Performance of Clinical Quantitative Measurement Methods as was agreed in pre-submission meeting Q171503.
The repeatability and within laboratory study was performed over 20 working days, with 2 runs per day and 2 replicates per run. 5 different samples were assessed using 1 reagent lot on 1 analyser.
| Repeatability and Within Laboratory Summary | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| N | Mean (g/L) | Within run | Between run | Between day | Total | |||||
| SD | CV % | SD | CV % | SD | CV % | SD | CV % | |||
| Level 1 | 80 | 0.425 | 0.008 | 1.9 | 0.017 | 3.9 | 0.019 | 4.5 | 0.027 | 6.3 |
| Level 2 | 80 | 0.681 | 0.010 | 1.5 | 0.027 | 4.0 | 0.021 | 3.0 | 0.036 | 5.2 |
| Level 3 | 80 | 1.148 | 0.017 | 1.4 | 0.038 | 3.3 | 0.033 | 2.9 | 0.053 | 4.6 |
| Level 4 | 80 | 4.041 | 0.058 | 1.4 | 0.085 | 2.1 | 0.107 | 2.6 | 0.148 | 3.7 |
| Level 5 | 80 | 6.273 | 0.063 | 1.0 | 0.161 | 2.6 | 0.074 | 1.2 | 0.188 | 3.0 |
Repeatability and Within Laboratory Results:
The between instrument precision study was performed over 6 working days, 2 instruments were tested each day with 2 replicates per instrument. 5 different samples were assessed using 1 reagent lot on 3 different analysers.
Between Instrument Results:
| | N | Mean
(mg/L) | Between
Instrument | |
|---------|----|----------------|-----------------------|------|
| | | | SD | CV % |
| Level 1 | 24 | 0.439 | 0.013 | 2.9 |
| Level 2 | 24 | 0.698 | 0.000 | 0.0 |
| Level 3 | 24 | 1.171 | 0.000 | 0.0 |
| Level 4 | 24 | 4.085 | 0.084 | 2.0 |
| Level 5 | 24 | 6.230 | 0.174 | 2.8 |
The between lot precision study was performed over 6 working days, 2 lots were tested each day with 2 replicates per lot. 5 different samples were assessed using 3 reagent lots on 1 analyser.
Between Lot Results:
| | N | Mean
(mg/L) | Between Lot | |
|---------|----|----------------|-------------|------|
| | | | SD | CV % |
| Level 1 | 24 | 0.442 | 0.023 | 5.2 |
| Level 2 | 24 | 0.704 | 0.028 | 4.0 |
| Level 3 | 24 | 1.174 | 0.038 | 3.2 |
| Level 4 | 24 | 4.087 | 0.033 | 0.8 |
| Level 5 | 24 | 6.416 | 0.117 | 1.8 |
7
The above results do not indicate any change in performance compared to the device cleared in K103824. The precision claims in the product insert therefore still accurately represent the performance of the modified kit and do not need to be amended.
b. Linearity/assay reportable range:
A linearity study was carried as per the original submission (K103824), where a dilution series was produced from a high pool with a known concentration of 8.59g/L and a low pool concentration of 0.10 g/L. Each diluted sample was tested in 3 replicates and a linear regression analysis was carried out. The linear regression equation was shown to be y=1.007x + 0.159 g/L with an R value of 0.999.
These results are comparable to those currently presented in the product insert and therefore do not indicate any change in performance compared to the device cleared in K103824. The linearity claims in the product insert therefore still accurately represent the performance of the modified kit and do not need to be amended.
c. Traceability, Stability, Expected values (controls, calibrators, or methods):
- i) Traceability:
The calibration of the assay is traceable to ERM-DA470k/IFCC.
ii) Kit Stability:
Accelerated Stability
Accelerated stability studies were carried out to verify that the stability of the kit is unchanged in accordance with ISO 23640:2015. 6 replicates of controls, internal reference and samples were tested over a period equivalent to 19 months and analysed in line with EP25-A with a maximum allowable difference of ±15% in order to verify the stability claim of 18 months. Reagents were stored at 37ºC to accelerate the study by a factor of 10.
Accelerated Stability Results
| Parameter | IR | Control | Sample | |||
|---|---|---|---|---|---|---|
| Low | High | 1 | 2 | 3 | ||
| Accelerated stability | ||||||
| achieved (days) | 165 | 57 | 57 | 57 | 57 | 57 |
| Equivalent at 4ºC (days) | 1625 | 561 | 561 | 561 | 561 | 561 |
| Stability required at 4ºC | ||||||
| (days) | 395 | 395 | 395 | 395 | 395 | 395 |
| Decision | Pass | Pass | Pass | Pass | Pass | Pass |
8
| Parameter | IR | Control | Sample | |||
|---|---|---|---|---|---|---|
| Low | High | 1 | 2 | 3 | ||
| Accelerated stability | ||||||
| achieved (days) | 57 | 57 | 132 | 57 | 57 | 76 |
| Equivalent at 4ºC (days) | 561 | 561 | 1300 | 561 | 561 | 748 |
| Stability required at 4ºC | ||||||
| (days) | 395 | 395 | 395 | 395 | 395 | 395 |
| Decision | Pass | Pass | Pass | Pass | Pass | Pass |
Batch 455407
Real Time Stability
To further support the results of the accelerated stability testing, a real time stability study is currently being carried out in accordance with EP25-A and as was agreed in pre-submission meeting Q171503.
On Board Stability
On-board stability studies were carried out as per the original submission and showed no difference in the cleared on-board stability claim
d. Detection limit.
The limit of quantitation (LoQ) for this assay is defined as the bottom of the measuring range, 0.02 g/L. The LoQ validation study was based on CLSI EP17-A2 Evaluation of the Detection Capability for Clinical Laboratory Measurement Procedures; Approved Guideline - 2nd Edition in accordance with pre-submission meeting Q171503. Four samples were tested using two reagent lots. The LoQ claim was validated by all the samples reporting within the acceptance criteria of an allowable CV of 8%.
The limit of detection (LoD) represents the lowest measurable analyte level that can be distinguished from zero, this was estimated as 0.007 g/L in the original submission and the limit of blank (LoB) was estimated to be 0.005 g/L. Additional testing was carried out following the antisera change and no change in performance was observed.
The results generated do not indicate any change in performance compared to the device cleared in K180827. The LoB, LoD and LoQ claims in the product insert therefore still accurately represent the performance of the modified kit and do not need to be amended.
e. Analytical specificity:
As per original submission (K103824)
f. Assay cut-off:
Not determined
9
3. Comparison studies:
a. Method comparison with predicate device:
A comparison study was performed by analysing 102 serum samples, 42 plasma samples using the modified Optilite IgA Kit and the cleared Optilite kit which is already commercially available. The study was carried out in accordance with pre-submission meeting Q171503. Bland Altman and Passing Bablok regression analysis generated the following results:
| Bland Altman Mean Bias | 95% Limits of Agreement | |
|---|---|---|
| 2.38% | -10.6 % to 15.37% | |
| Passing Bablok | Slope 95% CI | Intercept 95% CI |
| $y= 1.012x + 0.011$ | 1.001 to 1.027 | -0.006 to 0.044 |
| Correlation coefficient | ||
| 0.998 | ||
| Predicate Sample Range (g/L) | Test Samples Range (g/L) | |
| 0.032 – 45.050 | 0.050 – 41.49 |
The above results do not indicate any change in performance compared to the device cleared in K103824. The comparison claims in the product insert therefore still accurately represent the performance of the modified kit and do not need to be amended.
b. Matrix comparison:
Serum and plasma matrices were included in the above method comparison study. As per the original submission (K103824), no difference between matrices were observed.
3. Clinical studies:
a. Clinical Sensitivity: None determined
b. Clinical specificity: None determined
c. Other clinical supportive data (when a. and b. are not applicable): Not applicable
-
- Clinical cut-off:
None determined
- Clinical cut-off:
10
5. Expected values/Reference range:
Following the protocol agreed in Q171503, 20 samples from apparently healthy US donors were tested using the modified assay. The acceptance criteria for the transfer is ≤2 samples falling outside of the limits of the reference interval to be transferred.
Of the 20 samples tested, 19 gave results within the reference interval, ranging from 0.947 to 4.043 g/L. One sample was at the lower boundary of the reference interval (0.02 g/L) with a result of