(359 days)
CRYOcheck Factor VIII Deficient Plasma with VWF is for clinical laboratory use as a deficient substrate in the quantitative determination of Factor VIII activity in 3.2% citrated human plasma based on the activated partial thromboplastin time (APTT) assay. It is intended to be used in identifying factor VIII deficiency and as an aid in the management of hemophilia A in individuals aged 2 years and older. For in vitro diagnostic use
CRYOcheck Factor VIII Deficient Plasma with VWF is normal human citrated plasma which has been immunodepleted of factor VIII and to which an exogenous source of human von Willebrand Factor (vWF) has been added and buffered with HEPES. Factor VIII has been assayed at less than 1% of normal activity levels and vWF antigen and activity are >50%. It will be provided to users frozen in small-volume aliquots (25 vials of 1.0 mL, and 25 vials of 1.5 mL). Vials will be packaged into boxes; these will be frozen during the manufacturing process and will be shipped and stored frozen until use to preserve the integrity of the components
The provided FDA 510(k) summary for the "CRYOcheck Factor VIII Deficient Plasma with VWF" describes various performance studies and their results. Based on the document, here's a structured breakdown of the acceptance criteria and the study details:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly present a table of pre-defined acceptance criteria for each performance characteristic in a pass/fail format. Instead, it presents the results of various studies and implies that these results met internal or regulatory expectations for substantial equivalence to the predicate device. However, we can infer performance targets based on the documented results and common regulatory expectations for in vitro diagnostic devices.
Here's a table summarizing the reported device performance, with inferred acceptance "criteria" based on the conclusions drawn in the report:
| Performance Characteristic | Inferred Acceptance Criteria (Based on reported success) | Reported Device Performance |
|---|---|---|
| Precision (Multi-Reagent Lot) | <10% CV for controls and high FVIII samples; <0.5 SD for low/very low FVIII samples (implied as 'acceptable') | Aggregated Data (Lots 1, 2, and 3): - CRYOcheck Reference Control Normal: 5.7% CV - CRYOcheck Abnormal 1 Reference Control: 6.2% CV - CRYOcheck Abnormal 2 Reference Control: 5.2% CV - High FVIII Plasma Sample: 6.0% CV - Low FVIII Plasma Sample: 0.2 SD (11.1% CV) - Very Low FVIII Plasma Sample: 0.0 SD (24.1% CV) (Note: 24.1% CV for "Very Low" indicates higher variability, but the SD is 0.0, suggesting it met the SD criterion for this range) |
| Reproducibility (Multi-Reagent Lot Site-to-Site) | <10% CV for controls and high FVIII samples; <0.5 SD for low/very low FVIII samples (implied as 'acceptable') | Pooled 3-Site Data: - Reference Control Normal: 6.04% CV - Abnormal 1 Reference Control: 4.75% CV - Abnormal 2 Reference Control: 7.68% CV - High FVIII Plasma Sample: 5.07% CV - Low FVIII Plasma Sample: 0.18 SD (9.39% CV) - Very Low FVIII Plasma Sample: 0.04 SD (38.56% CV) (Note: 38.56% CV for "Very Low" indicates higher variability, but the SD is 0.04, suggesting it met the SD criterion for this range) |
| Linearity/Assay Reportable Range | Demonstration of linearity across the claimed reportable range (implied as 'acceptable' based on graphical analysis or statistical fit). | Linearity Range: 0 to 230% FVIII activity. The study concluded this range is supported. |
| Reference Interval | Establishment of a clinically meaningful and statistically derived reference interval from a healthy population. | Reference Interval: 62 to 163 % FVIII activity (calculated as the non-parametric 95% confidence interval, 2.5th to 97.5th percentiles). |
| Shelf-Life Stability | Maintenance of FVIII activity within acceptable limits over the claimed shelf-life. | A shelf-life stability claim of 24 months when stored at -40 °C to -80 °C, based on data up to 25 months (real-time study ongoing). |
| In-Use Stability | Maintenance of FVIII activity within acceptable limits for the claimed on-board and refrigerated stability periods. | A stability claim of 24 hours on board the instrument and at 2-8 °C. |
| Interferences | No significant interference from common substances at specified concentrations. | No interference from Hemoglobin (≤1000 mg/dL), Intralipid (≤2000 mg/dL), Bilirubin (conjugated, ≤4.0 mg/dL), Bilirubin (unconjugated, 40 mg/dL), Lupus Anticoagulant (≤1.8 dRVVT ratio), Warfarin (≤ INR ratio 2.72). Certain anticoagulants (Rivaroxaban, fondaparinux, dabigatran, emicizumated heparin, and low molecular weight heparin) were shown to interfere. |
| Recovery of FVIII Replacements | Accurate evaluation (100 ± 25%) of the potency of specified FVIII replacement therapies. | Accurately evaluated (100 ± 25%) Advate (92.84%), Afstyla* (97.38% with 2x correction factor), Elocate (94.90%), Jivi (104.49%), Novoeight (113.33%), and Wilate (94.92%) at concentrations 0.05 to 1.0 IU/mL. |
| Method Comparison | Demonstrating substantial equivalence to the predicate device via Passing-Bablok regression (e.g., slope close to 1, intercept close to 0, high correlation coefficient). | Overall (N=366): Slope = 1.16 (CI: 1.15 to 1.18), Intercept = -0.08 (CI: -0.25 to 0.13), Pearson Correlation Coefficient (r) = 0.96. Predicted biases at medical decision levels were reported (e.g., 0.37% at 1% FVIII, 13.70% at 100% FVIII). The study concluded it performed equivalently. |
| Sample Integrity | Support for claimed fresh sample stability and frozen storage stability, including freeze-thaw cycles. | Supported a fresh sample stability claim of 2 hours at room temperature and a frozen storage claim of 1.5 months at ≤-70 ℃, including up to two freeze-thaw cycles. |
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Multi-Reagent Lot Precision: Not explicitly stated as a "test set" sample size for patient plasma, but control samples were tested 80 replicates per sample per lot across 3 lots.
- Multi-Reagent Lot Site to Site Reproducibility: 270 replicates per sample (control or plasma) for the pooled data, across 3 sites and 3 lots. Patient samples included high, low, and very low FVIII plasma.
- Linearity/Assay Reportable Range: Fifteen sample dilutions, each tested in quadruplicate.
- Reference Interval: 136 normal, ostensibly healthy individuals.
- Shelf-Life Stability: Five replicates of one normal and two abnormal reference controls and two patient plasma samples per timepoint, across 3 lots.
- In-Use Stability: Five replicates of one normal and two abnormal reference controls and two patient plasma samples per timepoint, across 3 lots.
- Interferences: 10 replicates of spiked samples and 10 replicates of control for each possible interferent.
- Recovery of FVIII Replacements: Congenital FVIII deficient plasma spiked with six FVIII replacement therapies at seven concentrations (total 42 conditions).
- Method Comparison: 366 human plasma samples (from normal ostensibly healthy individuals, patients with congenital or acquired hemophilia A, patients with hemophilia B, patients with von Willebrand disease, hemophilia A patients on FVIII replacement therapies, and patients with other factor deficiencies). These samples were distributed across four sites.
- Sample Integrity: 94 plasma samples.
Data Provenance: The document does not specify the country of origin for any of the patient samples. All studies appear to be prospective in design, as they describe the testing of samples under controlled conditions to evaluate device performance characteristics.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
This device is an in vitro diagnostic (IVD) reagent for determining Factor VIII activity in human plasma, which is a quantitative measurement, not an interpretative one like image analysis. Therefore, the concept of "experts establishing ground truth" in the way it applies to diagnostic algorithms (e.g., radiologists for imaging) is not directly relevant here.
The "ground truth" for the performance studies is established by:
- The known concentrations/characteristics of reference controls.
- The actual FVIII activity levels as measured by a legally marketed predicate device (HemosIL Factor VIII Deficient Plasma) in the method comparison study.
- The carefully prepared spiked samples for linearity and recovery studies.
- The clinical diagnosis categories of patient samples (e.g., congenital hemophilia A).
There is no mention of human experts (e.g., pathologists, hematologists) adjudicating "ground truth" for individual cases in these studies beyond ensuring appropriate sample selection and handling. The performance is assessed against quantitative benchmarks and comparison with a known predicate.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
As mentioned above, the device performs a quantitative measurement, not an interpretative diagnosis requiring adjudication. Therefore, no adjudication method (like 2+1 or 3+1 for expert consensus on image interpretation) was used or is applicable for this type of IVD device testing. The "ground truth" is analytical and quantitative.
5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
No. An MRMC comparative effectiveness study is not applicable as this is an in vitro diagnostic reagent, not an AI-powered diagnostic tool that assists human readers. The device itself performs the measurement, and its performance is evaluated directly through analytical studies, not through its impact on human reader performance.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This refers to the performance of the device itself (the reagent in combination with instrumentation) without human interpretation affecting the measurement result. All the analytical performance studies (precision, reproducibility, linearity, stability, interferences, recovery, method comparison, sample integrity) represent the standalone performance of the CRYOcheck Factor VIII Deficient Plasma with VWF in conjunction with the specified automated APTT assay systems. The "human-in-the-loop" here refers to the user performing the test, but the performance characteristics relate to the analytical accuracy and reliability of the automated test method itself.
7. The type of ground truth used (expert concensus, pathology, outcomes data, etc)
The ground truth used in these studies is primarily analytical and quantitative:
- Known concentrations/values of commercially available reference controls.
- Known FVIII activity levels measured by a predicate device for method comparison.
- Expected FVIII activity levels in carefully fabricated samples (e.g., highly concentrated plasma diluted with congenital hemophilia A plasma for linearity, spiked samples for recovery).
- Clinical classification of patient samples (e.g., "patients with congenital or acquired hemophilia A") as the basis for sample selection in the method comparison and reference interval studies, though specific individual diagnoses are not the "ground truth" for each quantitative measurement, rather the context.
8. The sample size for the training set
This document describes a premarket notification (510(k)) for an in vitro diagnostic reagent. IVD reagents are not typically "trained" in the machine learning sense. Therefore, there is no training set in the context of an AI/ML algorithm. The studies detailed are analytical verification and validation studies to demonstrate performance and establish substantial equivalence to a predicate device.
9. How the ground truth for the training set was established
Since there is no training set for this type of device, this question is not applicable.
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September 13, 2023
Precision BioLogic Inc. Karen Black VP of Compliance and Product Development 140 Eileen Stubbs Avenue Dartmouth, Nova Scotia B3B 0A9 Canada
Re: K222831
Trade/Device Name: CRYOcheck Factor VIII Deficient Plasma with VWF Regulation Number: 21 CFR 864.7290 Regulation Name: Factor Deficiency Test Regulatory Class: Class II Product Code: GJT Dated: May 19, 2023 Received: May 19, 2023
Dear Karen Black:
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
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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,
Image /page/1/Picture/5 description: The image shows the text "Min Wu-S" in a large, sans-serif font. The text is black, and the background is white. The letters are evenly spaced and easy to read. There is a faint watermark in the background.
Min Wu, Ph.D. Branch Chief Division of Immunology and Hematology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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Indications for Use
510(k) Number (if known) K22831
Device Name
CRYOcheck Factor VIII Deficient Plasma with VWF
Indications for Use (Describe)
CRYOcheck Factor VIII Deficient Plasma with VWF is for clinical laboratory use as a deficient substrate in the quantitative determination of Factor VIII activity in 3.2% citrated human plasma based on the activated partial thromboplastin time (APTT) assay. It is intended to be used in identifying factor VIII deficiency and as an aid in the management of hemophilia A in individuals aged 2 years and older. For in vitro diagnostic use
| 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) |
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510(k) Summary cryocheck™ Factor VIII Deficient Plasma with VWF
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: K222831
| Submitter's | Precision BioLogic Inc. | |
|---|---|---|
| Information | 140 Eileen Stubbs Ave. | |
| Dartmouth, Nova Scotia B3B 0A9 | ||
| Canada | ||
| Contact Person | Karen M. Black, VP of Compliance & Product Development | |
| Phone: 902-468-6422, ext. 226, or 902-706-3125 | ||
| E-mail: kblack@precisionbiologic.com | ||
| Preparation Date | 25 August 2023 | |
| Device Trade Name | CRYOcheck™ Factor VIII Deficient Plasma with VWF | |
| Regulation Number and | 21 CFR 864.7290 | |
| Description | Factor Deficiency Test | |
| Regulatory | Classification | Class II |
| Information | Product Code | GJT, Plasma, Coagulation FactorDeficient; 21 CFR 864.7290 |
| Classification Panel | Hematology | |
| Predicate Device | HemosIL Factor VIII Deficient Plasma (K110237) | |
| Indication for Use/Intended Use | CRYOcheck Factor VIII Deficient Plasma with VWF is for clinicallaboratory use as a deficient substrate in the quantitativedetermination of Factor VIII activity in 3.2% citrated human plasmabased on the activated partial thromboplastin time (APTT) assay. It isintended to be used in identifying factor VIII deficiency and as an aid inthe management of hemophilia A in individuals aged 2 years andolder. For in vitro diagnostic use | |
| Device Description | CRYOcheck Factor VIII Deficient Plasma with VWF is normal humancitrated plasma which has been immunodepleted of factor VIII and towhich an exogenous source of human von Willebrand Factor (vWF) hasbeen added and buffered with HEPES. Factor VIII has been assayed atless than 1% of normal activity levels and vWF antigen and activity are>50%. It will be provided to users frozen in small-volume aliquots (25vials of 1.0 mL, and 25 vials of 1.5 mL). Vials will be packaged intoboxes; these will be frozen during the manufacturing process and willbe shipped and stored frozen until use to preserve the integrity of thecomponents |
| Comparison to Predicate | ||
|---|---|---|
| Item | Predicate | New Device |
| Proprietary andEstablished Names | HemosIL Factor VIII DeficientPlasma | CRYOCheck Factor VIII Deficientplasma with VWF |
| Manufacturer | Instrumentation Laboratory | Precision BioLogic |
| Similarities | ||
| Measurand | Human Factor VIII | Same |
| Classification ProductCode | GJT, Plasma, CoagulationFactor Deficient | Same |
| Regulation Section | 21 CFR 864.7290Factor Deficiency Test | 21 CFR 864.7290Factor Deficiency Test |
| Comparison to Predicate | ||
| Item | Predicate | New Device |
| Classification | Class II | Class II |
| Panel | 81 (Haematology) | 81 (Haematology) |
| Intended Use | HemosIL Factor VIII deficientplasma is human plasmadepleted for Factor VIII andintended for the in vitrodiagnostic quantitativedetermination of Factor VIIIactivity in citrated plasma,based on the activated partialthromboplastin time (APTT)assay, on the ACL TOP Familyanalyzers. HemosIL Factor VIIIdeficient plasma is indicatedfor use on patients who aresuspected of congenital oracquired deficiency based onthe activated partialthromboplastin time (APTT)assay results. | CRYOcheck Factor VIII DeficientPlasma with VWF is for clinicallaboratory use as a deficientsubstrate in the quantitativedetermination of Factor VIIIactivity in 3.2% citrated humanplasma based on the activatedpartial thromboplastin time(APTT) assay. It is intended tobe used in identifying factor VIIIdeficiency and as an aid in themanagement of hemophilia A inindividuals aged 2 years andolder. For in vitro diagnosticuse. |
| Assay Type | Quantitative (clot-basedmeasurement of FVIII) | Same |
| Methodology | Factor VIII activity in apatient's plasma is determinedby performing a modifiedactivated partialthromboplastin time test(APTT). Patient plasma isdiluted and added to plasmadeficient in Factor VIII.Correction of the clotting timeof the deficient plasma isproportional to theconcentration (% activity) ofthat factor in the patientplasma interpolated from acalibration curve. | Same |
| Expression of results | Quantitative; results areexpressed as percent activity.interpreted relative to acalibration curve. | Same |
| Instrument(s) | ACL TOP Family/ACL TOPFamily 50 Series | Same |
| Differences | ||
| Item | Predicate | New Device |
| Device Description | The HemosIL Factor VIII deficient plasma kit contains 10 x 1 mL vials of lyophilized human plasma that has been artificially depleted of factor VIII containing buffer and stabilizers. The residual factor VIII activity is less than or equal to 1% whereas von Willebrand Factor and the remaining intrinsic pathway factor levels are normal. | CRYOcheck Factor VIII Deficient Plasma with VWF is normal human citrated plasma which has been immunodepleted of factor VIII and to which an exogenous source of human von Willebrand Factor (vWF) has been added and buffered with HEPES. Factor VIII has been assayed at less than 1% of normal activity levels and vWF antigen and activity are >50%. It will be provided to users frozen in small-volume aliquots (25 vials of 1.0 mL, and 25 vials of 1.5 mL). Vials will be packaged into boxes; these will be frozen during the manufacturing process and will be shipped and stored frozen until use to preserve the integrity of the components. |
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PrecisionBioLogic
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Performance Summary:
All studies were performed using cRYocheck Factor VIII Deficient Plasma with VWF in a modified APTT assay with Instrumentation Laboratories' APTT SynthASil reagent to measure FVIII activity on Instrumentation Laboratories' ACL TOP Series or TOP 50 Series Instruments; the specific instrument(s) used for each study are indicated in the summary reports below.
Multi-Reagent Lot Precision
An internal precision study was performed using three (3) lots of cRYocheck Factor VIII Deficient Plasma with VWF in a modified APTT assay by two operators on an IL ACL TOP 700 CTS analyzer (K160276) in accordance with CLSI EP05-A3. The study quantified one normal and two abnormal reference controls and three patient plasma samples representing very low, and high levels of FVIII activity. Each sample was measured with each product lot in duplicate, twice a day for 20 days for a total of 80 replicates per sample per lot. The pooled results demonstrated a precision of <10% CV for all controls and the high FVIII activity plasma sample, and <0.5 SD for the low and very low FVIII plasma samples.
| Aggregated Data (Lots 1, 2 and 3) | |||||
|---|---|---|---|---|---|
| Sample | Mean FVIII | Within-Run Precision | Total Precision | ||
| (%) | SD | %CV | SD | %CV | |
| CRYOcheck Reference Control Normal | 100.4 | 3.5 | 3.4 | 5.7 | 5.7 |
| CRYOcheck Abnormal 1 Reference Control | 37.7 | 1.7 | 4.6 | 2.3 | 6.2 |
| CRYOcheck Abnormal 2 Reference Control | 11.3 | 0.4 | 3.7 | 0.6 | 5.2 |
| High FVIII Plasma Sample | 164 | 6.1 | 3.7 | 9.8 | 6.0 |
| Low FVIII Plasma Sample | 2.0 | 0.2 | 9.3 | 0.2 | 11.1 |
| Very Low FVIII Plasma Sample | 0.1 | 0.0 | 18.2 | 0.0 | 24.1 |
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Multi-Reagent Lot Site to Site Reproducibility
Reproducibility studies were conducted at three sites (one internal and two external) by two operators per site on IL ACL TOP 500. IL ACL TOP 700 CTS (K160276), and IL ACL TOP 750 CTS (K150877), analyzers using three lots of CRYOcheck Factor VIII Deficient Plasma with VWF in a modified APTT assay in accordance with CLSI EP05-A3. The study quantified one normal and two abnormal reference controls and three patient plasma samples representing very low. low and high levels of FVIII activity. Each sample was measured in triplicate, twice a day for 5 days at each site. The pooled data across three sites demonstrated a reproducibility of <10% CV for all controls and the high FVIII plasma sample, and <0.5 SD for the low and very low FVIII plasma samples.
| Pooled 3-Site Data | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sample | N | MeanFVIII (%) | Repeatability(Within-Run) | Between- Run | Between-Day | Between-Lot | Between-Site | Reproducibility(Total) | ||||||
| SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | |||
| Reference ControlNormal | 270 | 98.97 | 3.00 | 3.03 | 2.07 | 2.09 | 1.78 | 1.79 | 1.92 | 1.94 | 3.95 | 3.99 | 5.98 | 6.04 |
| Abnormal 1Reference Control | 270 | 37.40 | 1.25 | 3.33 | 0.63 | 1.68 | 0.61 | 1.63 | 0.80 | 2.14 | 0.44 | 1.16 | 1.77 | 4.75 |
| Abnormal 2Reference Control | 270 | 11.87 | 0.41 | 3.48 | 0.18 | 1.55 | 0.28 | 2.43 | 0.33 | 2.81 | 0.66 | 5.54 | 0.91 | 7.68 |
| High FVIII PlasmaSample | 269 | 166.37 | 6.54 | 3.93 | 2.08 | 1.25 | 1.45 | 0.87 | 4.34 | 2.61 | 1.78 | 1.07 | 8.44 | 5.07 |
| Low FVIII PlasmaSample | 270 | 1.93 | 0.11 | 5.84 | 0.06 | 3.08 | 0.03 | 1.81 | 0.08 | 4.01 | 0.09 | 5.01 | 0.18 | 9.39 |
| Very Low FVIIIPlasma Sample | 270 | 0.11 | 0.03 | 30.24 | 0.01 | 5.90 | 0.01 | 10.16 | 0.01 | 4.52 | 0.02 | 20.34 | 0.04 | 38.56 |
Linearity/Assay Reportable Range
A linearity study was conducted in accordance with CLSI EP06-2m Ed using three lots of cryocheck Factor VIII Deficient Plasma with VWF in a modified APTT assay to quantify FVIII on an IL ACL TOP 700 CTS instrument (K160276). A high FVIII (~260%) plasma was combined with congenital hemophilia A patient plasma (0% FVIII) to create fifteen sample dilutions with estimated FVIII activities in the range of 0 to 260% FVIII. Each level was tested in quadruplicate. The results support the linearity claim described below.
Linearity Range: 0 to 230% FVIII activity
Reference Interval
A reference interval study was conducted by two operators on two IL ACL TOP 700 CTS (K160276) analyzers in accordance with CLSI EP28-A3c using three lots of CRYOcheck Factor VIII Deficient Plasma with VWF and citrated plasma samples from 136 normal, ostensibly healthy individuals. The reference interval was established by calculating the non-parametric 95% confidence interval (2.5th to 97.5th percentiles).
Reference Interval: 62 to 163 % FVIII activity
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Stabilitv
Shelf-Life Stability
A shelf-life stability study was conducted in accordance with CLSI EP25-A using an IL ACL TOP 700 CTS instrument (K160276). Three lots of CRYOcheck Factor VIII Deficient Plasma with VWF were stored at -40 °C and ≤-70 °C and tested at t=0 and reqular intervals defined by the lotspecific pull schedule up to 37 months (real time study is ongoing). At each timepoint, five replicates of one normal and two abnormal reference controls and two patient plasma samples representing very low and high levels of FVIII activity levels were quantified in a modified APTT assay. The study has been completed up to 25 months and supports a shelf-life stability claim of 24 months when the product is stored at -40 °C to -80 °C.
In-Use Stability
An in-use stability study was conducted in accordance with CLSI EP25-A using an IL ACL TOP 700 CTS instrument (K160276). Three lots of CRYOcheck Factor VIII Deficient Plasma with VWF were maintained on board the analyzer (14.5 - 15.5 °C) for up to 25 hours and in a refrigerator (2–8 °C) for up to 25 hours. Each lot was used in a modified APTT assay to quantify five replicates of one normal and two abnormal reference controls and two patient plasma samples representing low and high levels of FVIII activity from each storage condition at defined timepoints. The data support a stability claim of 24 hours on board the instrument and at 2-8 °C.
Interferences
Interference studies were conducted according to CLSI EP07-A3 using a single lot of cRYocheck Factor VIII Deficient Plasma with VWF in a modified APTT assay on an IL ACL TOP 700 CTS instrument (K160276). Plasma samples were spiked with possible interferents, and 10 replicates were tested alongside 10 replicates of the corresponding blank matrix control. The following substances showed no interference up to the concentrations indicated:
| Possible Interferent | Concentration |
|---|---|
| Hemoglobin | ≤1000 mg/dL |
| Intralipid | ≤2000 mg/dL |
| Bilirubin (conjugated) | ≤4.0 mg/dL |
| Bilirubin (unconjugated) | 40 mg/dL |
| Lupus Anticoagulant | ≤1.8 dRVVT ratio |
| Warfarin | ≤ INR ratio 2.72 |
Rivaroxaban, fondaparinux, dabigatran, emicizumated heparin, and low molecular weight heparin were shown to interfere with the quantification of FVIII activity.
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Recovery of FVIII Replacements
A recovery study was conducted using a single lot of CRYOcheck Factor VIII Deficient Plasma with VWF in a modified APTT assay on an IL ACL TOP 700 CTS instrument (K160276). Congenital FVIII deficient plasma was spiked with six FVIII replacement therapies at seven concentrations and percent recovery was determined. CRYOcheck Factor VIII Deficient Plasma with VWF accurately evaluated (100 ± 25%) the potency of FVIII replacements including Advate, Afstyla, Elocate, Jivi, Novoeight, and Wilate at concentrations ranging from 0.05 to 1.0 IU/mL. There was an underestimation of Afstyla*, and a 2x correction factor was applied to the results based on manufacturer's recommendations.
| Product | Mean Percent Recovery (%) |
|---|---|
| Advate | 92.84 |
| Afstyla* | 97.38 |
| Eloctate | 94.90 |
| Jivi | 104.49 |
| Novoeight | 113.33 |
| Wilate | 94.92 |
- Per the manufacturer's recommendations, a chromogenic assay is recommended for measurement of Afstyla and results obtained by a one stage clotting assay will under recover by 50%.
Method Comparison
A method comparison study was conducted at four sites (one internal and three external) according to CLSI EP09c to compare the accuracy of factor VIII activity measurement when using cRYocheck Factor VIII Deficient Plasma with VWF in a modified APTT assay relative to a comparator device. Three hundred and sixty-six human plasma samples from normal ostensibly healthy individuals, from patients with congenital or acquired hemophilia A, patients with hemophilia B, patients with von Willebrand disease, hemophilia A patients on FVIII replacement therapies, and patients with other factor deficiencies were distributed across four sites and tested to quantify FVIII activity using a single lot of cRYocheck Factor VIII Deficient Plasma with VWF on IL ACL TOP 500, IL ACL TOP 700 CTS (K160276), and IL ACL TOP 750 CTS (K150877) analyzers. A second aliquot of each sample was tested using a modified APTT assay with HemosIL Factor VIII Deficient Plasma on an IL ACL TOP 750 instrument (K150877).
Results were compared by Passing-Bablok regression statistics show that CRYOcheck Factor VIII Deficient Plasma with VWF performed equivalently to the comparator method.
| N | Slope | Intercept | Pearson CorrelationCoefficient (r) | |||
|---|---|---|---|---|---|---|
| Value | 95% CI | Value | 95% CI | |||
| Site 1 | 115 | 1.15 | 1.12 to 1.19 | 0.17 | -0.38 to 0.64 | 0.93 |
| Site 2 | 125 | 1.19 | 1.16 to 1.22 | -0.26 | -0.48 to -0.09 | 0.97 |
| Site 3 | 108 | 1.10 | 1.06 to 1.15 | 0.97 | 0.24 to 1.99 | 0.98 |
| Site 4 | 18 | 1.22 | 0.95 to 1.31 | 1.19 | -3.99 to 13.96 | 0.98 |
| Overall | 366 | 1.16 | 1.15 to 1.18 | -0.08 | -0.25 to 0.13 | 0.96 |
Absolute predicted biases at medical decision levels are reported below.
| FVIII activity (%) | Predicted Bias (%) | Lower CI (%) | Upper CI (%) |
|---|---|---|---|
| 1 | 0.37 | -1.42 | 2.17 |
| 5 | 0.91 | -0.79 | 2.62 |
| 50 | 6.97 | 5.85 | 8.09 |
| 100 | 13.70 | 11.84 | 15.56 |
{9}------------------------------------------------
Sample Integrity
A sample integrity study was conducted at two external sites to assess the stability of fresh plasma samples at room temperature, when stored frozen at ≤-70 °C and after up to two freeze thaw cycles. The FVIII activity of ninety-four plasma samples was measured using one lot of cryocheck Factor VIII Deficient Plasma with VWF on IL ACL TOP 300 and IL ACL TOP 700 (K160276) analyzers. Results were compared using weighted Deming regression analysis and support a fresh sample stability claim of 2 hours at room temperature and a frozen storage claim of 1.5 months at ≤-70 ℃, including up to two freeze thaw cycles.
Conclusion
The performance testing results demonstrate that CRYOcheck Factor VIII Deficient Plasma with VWF is substantially equivalent to the predicate device, HemosIL Factor VIII Deficient Plasma (K110237) and that the assay is effective for its labeled intended use.
§ 864.7290 Factor deficiency test.
(a)
Identification. A factor deficiency test is a device used to diagnose specific coagulation defects, to monitor certain types of therapy, to detect coagulation inhibitors, and to detect a carrier state (a person carrying both a recessive gene for a coagulation factor deficiency such as hemophilia and the corresponding normal gene).(b)
Classification. Class II (performance standards).