QStat Cartridge
Device Facts
| Record ID | K213917 |
|---|---|
| Device Name | QStat Cartridge |
| Applicant | Hemosonics, LLC |
| Product Code | QFR · Hematology |
| Decision Date | Nov 29, 2022 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 864.5430 |
| Device Class | Class 2 |
Indications for Use
The QStat® Cartridge is a multi-channel cartridge that provides semi-quantitative indications of the coagulation and clot lysis state of a 3.2% citrated venous whole blood sample using the Quantra® Hemostasis Analyzer. The QStat Cartridge includes tests to assess coagulation via the intrinsic pathways and includes a test with tranexamic acid to evaluate clot lysis characteristics. The QStat Cartridge is intended for in vitro diagnostic use by trained professionals at the point-of-care and in clinical laboratories to evaluate the viscoelastic properties of whole blood by means of the following functional parameters: Clot Time (CT), Clot Stiffness (CS), Fibrinogen Contribution to Clot Stiffness (FCS), Platelet Contribution to Clot Stiffness (PCS), and Clot Stability to Lysis (CSL). The QStat Cartridge is indicated for the evaluation of blood coagulation and clot lysis in patients age 18 years and older to assess possible hypocoagulable conditions in trauma and liver transplantation procedures. Results obtained with the OStat Cartridge should not be the sole basis for patient diagnosis. For prescription use only.
Device Story
Single-use, multi-channel plastic cartridge for Quantra Hemostasis Analyzer; assesses coagulation and clot lysis in hospital settings (POC/lab). Input: 3.2% citrated venous whole blood. Operation: Sonic Estimation of Elasticity via Resonance (SEER) Sonorheometry; ultrasound pulses generate shear waves to measure shear modulus (stiffness) during coagulation. Cartridge contains lyophilized reagents (kaolin, thromboplastin, polybrene, abciximab, tranexamic acid) in four channels. Output: Clot Time (CT), Clot Stiffness (CS), Fibrinogen Contribution to Clot Stiffness (FCS), Platelet Contribution to Clot Stiffness (PCS), and Clot Stability to Lysis (CSL). Results displayed on analyzer screen as dials, stiffness curves, and trends. Assists clinicians in managing coagulation status during surgery/trauma; helps identify fibrinolysis and hypocoagulable states.
Clinical Evidence
Multi-center prospective observational study (n=125 liver transplant, n=159 trauma, n=5 normal). Compared QStat to ROTEM delta. Linear regression showed strong correlation (Pearson r=0.80-0.95). Clinical agreement for lysis detection (CSL vs EXTEM ML) was 92.6% overall. Additional comparison with TEG 6S (n=52) showed 91.7% agreement for lysis. Reader study (n=10) confirmed >95% correct interpretation of results.
Technological Characteristics
Single-use, 4-channel plastic cartridge. Sensing principle: SEER Sonorheometry (ultrasonic pulses). Reagents: Lyophilized beads (kaolin, thromboplastin, tranexamic acid, polybrene, abciximab, calcium). Dimensions: Disposable cartridge for Quantra Hemostasis Analyzer. Connectivity: Networked/standalone analyzer with touchscreen interface. Sterilization: Not specified. Software: Embedded firmware for signal processing and parameter calculation.
Indications for Use
Indicated for patients age 18+ undergoing trauma or liver transplantation procedures to assess hypocoagulable conditions. Used for in vitro diagnostic evaluation of blood coagulation and clot lysis.
Regulatory Classification
Identification
A coagulation system for the measurement of whole blood viscoelastic properties in perioperative patients is an in vitro diagnostic device used to evaluate blood coagulation, fibrinolysis, or both, in perioperative patients, as an aid in the assessment of coagulopathies when used in conjunction with clinical signs and symptoms and other clinical and laboratory findings.
Special Controls
The special controls for this device are:
*Classification.* Class II (special controls). The special controls for this device are:(1) Design verification and validation must include detailed documentation of, and results from, the following: (i) A study assessing precision using protocols determined to be acceptable by FDA, to cover the measurement range for each reported parameter (test output). Testing must include native specimens with coagulation profiles representative of the intended use population. In order to cover the measuring range, testing may include a limited number of contrived specimens, not to exceed 10 to 20 percent, or as otherwise deemed appropriate by FDA. The contrived specimens must be prepared to resemble clinical specimens. This testing must evaluate repeatability and reproducibility and provide assessments of within-run, within-day, between-run, between-day, between-reagent lot, between-instrument, between-site, and between-operator precision, as applicable to the system; (ii) Studies that demonstrate the performance of each parameter (test output) throughout the claimed measurement range, to include linearity studies or dose-response studies, as applicable to the parameter (test output); (iii) Potential interferent study that includes evaluation of hemolyzed and lipemic samples as potential interferents; exogenous and endogenous interferents associated with each patient population intended for use with the device, and which might be expected to affect assay performance, must be evaluated; and potential interferents that are specific for, or related to, the technology or methodology of the device. Evaluation of all potential interferents must be performed using a protocol determined to be acceptable to the FDA ( *e.g.,* an FDA-recognized standard) and include both normal and abnormal specimens covering coagulation profiles representative of the intended use population;(iv) A study that evaluates specimen stability under the intended conditions for specimen collection, handling, and storage, using samples that cover the coagulation profiles representative of the intended use population, and using protocols determined to be acceptable by FDA; (v) A multisite clinical study, determined to be acceptable by FDA, demonstrating performance, relative to clinically relevant and clinically validated laboratory test(s) for each parameter (test output). Further, the study must meet all of the following criteria: (A) The study must be performed in the intended use population and include representation from all patient populations for whom the device is intended to be used. Potential endogenous and exogenous interferents for each target patient population must be evaluated or known prior to the study; (B) The study must be conducted at a minimum of three external sites representative of the intended use setting by the intended operators; (C) Test samples must be collected at time intervals relevant to the device's use in the intended use population; (D) Clinical specimens, which cover coagulation profiles representative of the intended use population, must be evaluated at each of the three clinical sites in the study; (E) Analysis of the concordance of clinical interpretation of patient coagulation status made from individual test parameter (test output) results as compared to clinical interpretation of coagulation status from a clinically relevant laboratory test or tests ( *e.g.,* a comparative viscoelastic device or standard laboratory tests) must be conducted; and(F) Expected (reference) values for each parameter (test output) must be demonstrated by testing a statistically appropriate number of samples from apparently healthy normal individuals; (vi) For a device with a user interface that has information that needs to be interpreted by the user in correctly using the device to achieve the intended test results or a device that does not provide a final output that is a comprehensive interpretation of all parameter (test output) results, a study evaluating the ability of device users to correctly interpret results; (vii) For any device indicated to guide blood product use, a clinical outcome study determined to be acceptable by FDA that specifically validates the device's indicated use in guiding blood product use; and (viii) For any device indicated to guide use of medication, a clinical outcome study determined to be acceptable by FDA that specifically validates the device's indicated use in guiding use of medication. (2) The labeling required under § 809.10(b) of this chapter must include the following: (i) A summary of results from the study required by paragraph (b)(1)(i) of this section, including repeatability, reproducibility, and assessments of within-run, within-day, between-run, between-day, between-reagent lot, between-instrument, between-site, and between-operator precision, as applicable to the system. (ii) The claimed measurement range of each parameter (test output), as supported by demonstrated performance of the parameter (test output) throughout the claimed measurement range, including studies required by paragraphs (b)(1)(i) through (iii) and (v) of this section, and, if applicable, paragraphs (b)(1)(vii) and (viii) of this section. (iii) Identification of known interferents, including all endogenous, exogenous, technology-specific, and patient population-specific interferents, specific to each parameter (test output). The information must include the concentration(s) or level(s) at which interference was found to occur and the concentration range or levels at which interference was not found to occur. (iv) Information regarding the multisite clinical study required by paragraph (b)(1)(v) of this section, including: (A) Each patient population evaluated; (B) Each intended use setting and the operators; (C) A summary of the results, including the concordance analysis to clinically relevant laboratory test(s); and (D) Demonstrated expected (reference) values for each parameter (test output). (3) The labeling required under § 809.10 of this chapter must include the following: (i) A limiting statement that the result(s) from the device is(are) not intended to be used as the sole basis for a patient diagnosis. (ii) Unless appropriate clinical outcome studies are done in accordance with paragraph (b)(1)(vii) of this section that specifically validate an indication for the device's use in guiding blood product use, a limiting statement that the device has not been evaluated to guide blood product use. (iii) Unless appropriate clinical outcome studies are done in accordance with paragraph (b)(1)(viii) of this section that specifically validate an indication for the device's use in guiding use of medication, a limiting statement that the device has not been evaluated to guide use of medication.
Predicate Devices
- ROTEM delta Thromboelastometry System (K083842)
- EXTEM Assay, FIBTEM Assay, APTEM Assay for the ROTEM delta Thromboelastometry System (K101533)
Submission Summary (Full Text)
{0}
FDA
U.S. FOOD & DRUG
ADMINISTRATION
# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY
ASSAY ONLY
## I Background Information:
A 510(k) Number
K213917
B Applicant
HemoSonics, LLC
C Proprietary and Established Names
QStat Cartridge
D Regulatory Information
| Product Code(s) | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| QFR | Class II | 21 CFR 864.5430 - Coagulation system for the measurement of whole blood viscoelastic properties in perioperative patients | HE - Hematology |
## II Submission/Device Overview:
A Purpose for Submission:
Clearance of a new device
B Measurand:
Clot Time (CT), Clot Stiffness (CS), Fibrinogen Contribution to Clot Stiffness (FCS), Platelet Contribution to Clot Stiffness (PCS), and Clot Stability to Lysis (CSL)
C Type of Test:
Semi-quantitative
Food and Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993-0002
www.fda.gov
{1}
K213917 - Page 2 of 25
## III Intended Use/Indications for Use:
### A Intended Use(s):
See Indications for Use below.
### B Indication(s) for Use:
The QStat Cartridge is a multi-channel cartridge that provides semi-quantitative indications of the coagulation and clot lysis state of a 3.2% citrated venous whole blood sample using the Quantra Hemostasis Analyzer. The QStat Cartridge includes tests to assess coagulation via the intrinsic and extrinsic pathways and includes a test with tranexamic acid to evaluate clot lysis characteristics.
The QStat Cartridge is intended for in vitro diagnostic use by trained professionals at the point-of-care and in clinical laboratories to evaluate the viscoelastic properties of whole blood by means of the following functional parameters: Clot Time (CT), Clot Stiffness (CS), Fibrinogen Contribution to Clot Stiffness (FCS), Platelet Contribution to Clot Stiffness (PCS), and Clot Stability to Lysis (CSL).
The QStat Cartridge is indicated for the evaluation of blood coagulation and clot lysis in patients age 18 years and older to assess possible hypocoagulable and hypercoagulable conditions in trauma and liver transplantation procedures.
Results obtained with the QStat Cartridge should not be the sole basis for patient diagnosis.
For prescription use only.
### C Special Conditions for Use Statement(s):
Rx - For Prescription Use Only
For in vitro diagnostic use
### D Special Instrument Requirements:
Quantra Hemostasis Analyzer
## IV Device/System Characteristics:
### A Device Description:
The QStat Cartridge is a single-use, multi-channel disposable plastic cartridge used with the Quantra Hemostasis Analyzer to assess a patient's coagulation and clot lysis in a hospital setting (point of care or laboratory) during trauma and liver transplantation procedures. The QStat Cartridge consists of four independent channels that can be tested simultaneously with Sonic Estimation of Elasticity via Resonance (SEER) Sonorheometry.
Each QStat Cartridge is pre-filled with reagents individually sealed in an airtight pouch. After a QStat Cartridge is removed from its primary packaging, it is inserted into the Quantra
{2}
Hemostasis Analyzer instrument dock. A venous whole blood sample, collected in a 3.2% sodium citrate anticoagulant blood collection tube (minimum volume 2.7 mL), is attached directly to the cartridge and the test is initiated using the touch screen interface on the Quantra Hemostasis Analyzer. The cartridge is the only component of the Quantra system that is in direct contact with blood. The fluidic system within the instrument draws the sample into the cartridge where it is warmed to 37°C, aliquoted, introduced and mixed with the lyophilized reagents, and analyzed. When the test is complete, the cartridge is released from the dock to be disposed of in an appropriate biosafety sharps container.
Each channel of the cartridge contains prefilled lyophilized reagents in the form of beads that enable differential testing without the need for any reagent preparation or pipetting before testing. The assay provides the following information for each patient sample: Clot Time (CT), Clot Stiffness (CS), Fibrinogen Contribution to Clot Stiffness (FCS), Platelet Contribution to Clot Stiffness (PCS) and Clot Stability to Lysis (CSL).
QStat Cartridge Reagents and Test function per Channel
| Channel | Reagents | QStat Cartridge Output Parameter (units of measure) |
| --- | --- | --- |
| Measured Parameters | | |
| 1 | Kaolin, calcium, buffers and stabilizers | Clot Time (CT) (seconds) |
| 2 | Thromboplastin, tranexamic acid (TXA), polybrene, calcium, buffers, and stabilizers | No direct output (see calculated parameters) |
| 3 | Thromboplastin, polybrene, calcium, buffers, and stabilizers | Clot Stiffness (CS) (hectopascals) |
| 4 | Thromboplastin, polybrene, abciximab, calcium, buffers, and stabilizers | Fibrinogen Contribution to Clot Stiffness (FCS) (hectopascals) |
| Calculated Parameters | | |
| 2 & 3 | See above | Clot Stability to Lysis (CSL) (percent) |
| 3 & 4 | See above | Platelet Contribution to Clot Stiffness (PCS) (hectopascals) |
The analyzer displays the test results in three different views: dial display screen, stiffness curves data, and trend screen. The dial display screen is the primary viewing screen and has a dial for each of the five output parameters. Each dial shows the reference range, assay measurement range, parameter abbreviation, and the numerical result for the corresponding parameter. The stiffness curves are a graphical display of shear modulus measurements over time that enable the user to view the development of clot stiffness over time. The trends screen displays results from a patient for up to six time points.
There are two levels of external QStat Controls (QSL1 and QSL2). QC is manufactured by HemoSonics and will be commercially available separately from the Quantra Hemostasis Analyzer and QStat Cartridge. The QSL1 and QSL2 are recommended to be run monthly, changing cartridge lots, changing control lots, or after significant changes are made to the Quantra instrument (e.g., software update). QSL1 and QSL2 are reconstituted by the end user with the provided diluent and loaded onto the QStat by the same method as patient samples. The
K213917 - Page 3 of 25
{3}
plastic diluent vial is shipped with an extender that serves to guide the vial into the cartridge’s evacuated sample tube attachment, after reconstitution. The QStat Controls contain materials to test the measured output parameters for the QStat Cartridge: CT, CS, and FCS, as well as the calculated parameters, CSL and PCS.
The Quantra Cleaning Cartridge is an accessory for the Quantra Hemostasis Analyzer and is intended to be used for simple, periodic cleaning.
## B Principle of Operation:
The QStat Cartridge uses Sonic Estimation of Elasticity via Resonance (SEER) Sonorheometry, a ultrasound-based technology, which uses ultrasound pulses to quantify the shear modulus (i.e., stiffness) of a blood sample during the process of coagulation and clot lysis. A focused ultrasound pulse is transmitted into the blood sample to generate a shear wave, causing the sample to resonate once the clot begins to form. Multiple parameters measured from the four channels of the cartridge provide information about the functional role of the coagulation factors, fibrinogen, platelets, and clot lysis factors in the sample.
## Clot Time (CT) Test
CT is directly measured in Channel #1 using kaolin to provide contact surface activation of coagulation via the intrinsic pathway. Kaolin is an aluminum silicate mineral with a negatively charged surface. Calcium acetate is included to re-calcify the blood sample used for testing. Prolongation of the intrinsic pathway clot time is likely due to deficiencies in intrinsic pathway coagulation factors, presence of anticoagulants, or inhibitors that affect the intrinsic pathway.
## Clot Stiffness (CS) Test
CS is directly measured in Channel #3 and is determined by measuring the stiffness after the clot has formed. using thromboplastin (tissue factor) to activate the extrinsic pathway of coagulation. The test includes polybrene, a reagent that neutralizes heparin. Calcium acetate is included to re-calcify the blood sample used for testing. This test allows an evaluation of the total clot stiffness from the combined contributions from both platelets and fibrinogen.
## Fibrinogen Contribution to Clot Stiffness (FCS) Test
FCS is directly measured in Channel #4 using thromboplastin (tissue factor) to activate the extrinsic pathway of coagulation, in combination with a reagent that inhibits platelet aggregation and contraction (Abciximab). Abciximab is the Fab fragment of a monoclonal antibody that binds on the platelet surface receptor GPIIb/IIIa. Polybrene is included to neutralize heparin in addition to calcium acetate to re-calcify the blood sample used for testing. This test allows an evaluation of the contribution of functional fibrinogen to clot stiffness without the effect of heparin anticoagulation. In addition, when used in combination with the Clot Stiffness (CS) Test, the contribution of platelets to the clot stiffness can be determined.
Two additional functional parameters are calculated:
## Platelet Contribution to Clot Stiffness (PCS)
PCS is a functional parameter that is calculated as the difference between the overall CS measured in Channel #3 and the FCS measured in Channel #4, reported in hectoPascals (hPa).
## Clot Stability to Lysis (CSL)
K213917 - Page 4 of 25
{4}
CSL is a functional parameter that is calculated from Channel #2 and # 3 and is reported as a percent after the maximum stiffness in Channel #3 is detected. The CSL reports the loss in clot stiffness that is likely due to the influence of fibrinolysis on a scale from 100% (no clot lysis) to 10% (significant clot degradation).
V Substantial Equivalence Information:
A Predicate Device Name(s): ROTEM delta Thromboelastometry System, EXTEM Assay, FIBTEM Assay, APTEM Assay for the ROTEM delta Thromboelastometry System
B Predicate 510(k) Number(s): K083842, K101533
C Comparison with Predicate(s):
| Device & Predicate Device(s): | K213917 | K083842 | K101533 |
| --- | --- | --- | --- |
| Device Trade Name | QStat Cartridge | ROTEM® delta Thromboelastometry System | EXTEM® Assay, FIBTEM® Assay, APTEM® Assay for the ROTEM® delta Thromboelastometry System |
| General Device Characteristic Similarities | | | |
| Intended Use/Indications For Use | The QStat Cartridge is a multi-channel cartridge that provides semi-quantitative indications of the coagulation and clot lysis state of a 3.2% citrated venous whole blood sample using the Quantra Hemostasis Analyzer. The QStat Cartridge includes tests to assess coagulation via the intrinsic and extrinsic pathways and includes a test with tranexamic acid to evaluate clot lysis characteristics. The QStat Cartridge is intended for in vitro diagnostic use by trained professionals at | The ROTEM® delta Thromboelastometry System is designed for in vitro diagnostic use by professionals in a laboratory environment. The ROTEM® delta is intended to provide a qualitative and quantitative indication of the coagulation state of a blood sample. For this purpose the ROTEM® delta records the clot firmness changes in a sample of citrated whole blood as the sample clots, retracts and lyses in real time. The analyzer output consists of a qualitative graphical | The EXTEM® assay is a semi-quantitative in vitro diagnostic assay used to monitor the coagulation process via the extrinsic pathway in citrated whole blood specimens on the ROTEM® delta Thromboelastometry System. Clotting characteristics are described by the functional parameters Clotting Time (CT), Speed of Clot formation (CFT and alpha angle), Clot Firmness (A20/MCF) and Clot Lysis (LOT, ML, LI(x)), CFT and alpha (Speed of Clot |
K213917 - Page 5 of 25
{5}
K213917 - Page 6 of 25
| | the point-of-care and in clinical laboratories to evaluate the viscoelastic properties of whole blood by means of the following functional parameters: Clot Time (CT), Clot Stiffness (CS), Fibrinogen Contribution to Clot Stiffness (FCS), Platelet Contribution to Clot Stiffness (PCS), and Clot Stability to Lysis (CSL).
The QStat Cartridge is indicated for the evaluation of blood coagulation and clot lysis in patients age 18 years and older to assess possible hypocoagulable and hypercoagulable conditions in trauma and liver transplantation procedures.
Results obtained with the QStat Cartridge should not be the sole basis for patient diagnosis.
For prescription use only. | representation (mirrored coagulation curve – clot firmness over time) and several defined numerical parameters describing the curve quantitatively.
The in-TEM® assay is a semi-quantitative in vitro diagnostic assay used to monitor the coagulation process via the intrinsic pathway in citrated whole blood specimens. Clotting characteristics are described by the functional parameters Clotting Time (CT), Speed of Clot formation (CFT and alpha angle), Clot Firmness (A20/MCF) and Clot Lysis (LOT, ML, LI(x)). The assay is intended for professional use in the clinical laboratory on the ROTEM® delta Instrument.
The hep-TEM® assay is a semi-quantitative in vitro diagnostic assay used to monitor the coagulation process via the intrinsic pathway in the presence of heparin, in citrated whole blood specimens. Clotting characteristics are described by the functional parameters Clotting Time (CT), Speed of Clot formation (CFT and alpha angle), Clot Firmness (A20/MCF) and Clot Lysis (LOT, ML, LI(x)). The | Formation) are complementary parameters and should be used in conjunction with the main parameters Clotting Time (CT) and Clot Firmness (A20/MCF).
The FIBTEM® assay is a semi-quantitative in vitro diagnostic assay on the ROTEM® delta Thromboelastometry System to monitor the clot firmness of a citrated whole blood specimen after blocking platelet contribution to the clot firmness. The fibTEM® is always used in conjunction with exTEM® Clotting characteristics are described by the functional parameter Clot Firmness (A20/MCF).
The APTEM® assay is a semi-quantitative in vitro diagnostic assay on the ROTEM® delta Thromboelastometry System to monitor the clot firmness of a citrated whole blood specimen after blocking hyperfibrinolysis by aprotinin. The ap-TEM® is always used in conjunction with ex-TEM®. Clotting characteristics are described by the functional parameters Clotting Time (CT), Speed of Clot formation (CFT and alpha angle), Clot Firmness |
| --- | --- | --- | --- |
{6}
K213917 - Page 7 of 25
| | | assay is intended for professional use in the clinical laboratory on the ROTEM® delta Instrument. The NATEM® assay is a semi-quantitative in vitro diagnostic assay used to monitor the coagulation process contact activated by the surface of the measurement cell, in citrated whole blood specimens. Clotting characteristics are described by the functional parameters Clotting Time (CT), Speed of Clot formation (CFT and alpha angle), Clot Firmness (A20/ MCF) and Clot Lysis (LOT, ML, LI(x)). The assay is intended for professional use in the clinical laboratory on the ROTEM® delta Instrument. The star-TEM® reagent is intended for use as recalcification reagent in the NATEM and in-TEM on the ROTEM® delta Thromboelastometry System. | (A20/MCF) and Clot Lysis (LOT, ML, LI(x)). CFT and alpha (Speed of Clot Formation) are complementary parameters and should be used in conjunction with the main parameters Clotting Time (CT) and Clot Firmness (A20/MCF). Each assay, APTEM, EXTEM and FIBTEM is performed on the ROTEM delta analyzer which has the following indication for use: The indication for ROTEM® delta is in adult patients when an evaluation of their blood coagulation properties is desired. Coagulation evaluations with the ROTEM® delta system are commonly used to assess clinical conditions in organ transplantation, cardiovascular surgery, cardiology procedures and trauma to access post-operative hemorrhage and/or thrombosis. |
| --- | --- | --- | --- |
| Sample Type | 3.2% sodium citrated whole blood | Citrated whole blood | Citrated whole blood |
| Results Display | Graphical (curves) and numerical display of patient results | Same | Same |
| Measurands | Clot time (CT) | Same | Same |
| | Clot Stiffness (CS) | Same
Reported as EXTEM | Same
Reported as EXTEM |
{7}
K213917 - Page 8 of 25
| | Fibrinogen Contribution to Clot Stiffness (FCS) | A20 (Clot Firmness) | A20 (Clot Firmness) |
| --- | --- | --- | --- |
| | | Same
Reported as FIBTEM A20 | Same
Reported as FIBTEM A20 |
| **Reagents** (extrinsic pathway) | Thromboplastin | Same | Same |
| **General Device Characteristic Differences** | | | |
| Instrument | Quantra Hemostasis Analyzer | ROTEM® delta instrument | ROTEM® delta instrument |
| Sample Volume | 3.0 mL citrated whole blood sample (2.7 mL whole blood + citrate) | 300 µL per assay (in-TEM, hep-TEM, NATEM, star-TEM) | 300 µL per assay (EXTEM, FIBTEM, APTEM) |
| Sample Preparation | Automated | Manual | Manual |
| Signal Generation | Ultrasonic pulses directed into a stationary well | Oscillating pin in stationary cup | Oscillating pin in stationary cup |
| Assay Output | Platelet Contribution to Clot Stiffness (PCS) | Output not directly provided but can be calculated offline from comparison of EXTEM and FIBTEM | Output not directly provided but can be calculated offline from comparison of EXTEM and FIBTEM |
| | Clot Stability to Lysis (CSL) | EXTEM and APTEM ML/LI60 and difference calculated offline. | EXTEM and APTEM ML/LI60 and difference calculated offline. |
| Reagents | Kaolin (intrinsic pathway activator) | Ellagic acid (intrinsic pathway activator) | Ellagic acid (intrinsic pathway activator) |
| | Abciximan (platelet inhibitor) | Cytochalasin D (platelet inhibitor) | Cytochalasin D (platelet inhibitor) |
| | Tranexamic acid (fibrinolysis inhibitor) | Aprotinin (fibrinolysis inhibitor) | Aprotinin (fibrinolysis inhibitor) |
| Principle of Operation | SEER Sonorheometry uses ultrasound pulses to quantify the shear modulus (i.e., stiffness) of a blood sample during the process of coagulation and clot lysis. A focused ultrasound pulse is transmitted into the blood sample to generate a shear wave, causing the sample to resonate once the clot | Shear elasticity of a coagulating sample by motion of an oscillating pin in a stationary cup. The motion of the pin is detected by an optical detection system. Data are processed and analyzed by a computer with special software. | Shear elasticity of a coagulating sample by motion of an oscillating pin in a stationary cup. The motion of the pin is detected by an optical detection system. Data are processed and analyzed by a computer with special software. |
{8}
| | begins to form. | | |
| --- | --- | --- | --- |
| QC Materials | The Quantra Analyzer performs internal quality control checks of all system components at regular intervals and during each phase of a test run on a cartridge to verify that the instrument hardware and all subsystems are functioning properly. Two levels of external QStat Controls (Level 1 and Level 2) are available and supplied separately. | ROTOL N (Level 1) and ROTOL P (Level 2) | ROTOL N (Level 1) and ROTOL P (Level 2) |
VI Standards/Guidance Documents Referenced:
CLSI EP05-A3: Evaluation of Precision of Quantitative Measurement Procedures; Approved Guideline - Third Edition
CLSI EP07: Interference Testing in Clinical Chemistry; Third Edition
CLSI EP25-A: Evaluation of Stability of In Vitro Diagnostic Reagents; Approved Guideline
CLSI EP28-A3c: Defining, Establishing and Verifying Reference Intervals in the Clinical Laboratory; Approved Guideline - Third Edition
CLSI EP37: Supplemental Tables for Interference Testing in Clinical Chemistry. First Edition
VII Performance Characteristics (if/when applicable):
A. Analytical Performance:
1. Precision/Reproducibility:
a. Single-site precision with Quantra QStat Controls
A single-site precision study was performed over the course of 20 days, with two runs per day, and two replicates per run using QStat Control Level 1 (QSL1) and Level 2 (QSL2). A single Quantra Hemostasis Analyzer and a single lot of QStat Cartridges were utilized in the study, which was performed by a single operator. The results of this study demonstrated within-laboratory precision (total) of 0.0% – 9.5% CV for QSL1 and 0.6% – 9.3% CV for QSL2 parameters.
K213917 - Page 9 of 25
{9}
Single-site precision study with Quantra QStat Controls result summary:
| QSLI | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Parameter | N | Mean | Repeatability | | Between-Day | | Between-Run | | Total (Within-laboratory) | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| CT (sec) | 80 | 158.6 | 4.3 | 2.7 | 1.5 | 1.1 | 3.2 | 2.0 | 5.6 | 3.5 |
| CSL(%) | 80 | 100 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| CS (hPa) | 80 | 14.1 | 0.7 | 5.3 | 0.2 | 1.7 | 0.1 | 1.0 | 0.8 | 5.6 |
| FCS (hPa) | 80 | 14.7 | 1.3 | 8.6 | 0.4 | 2.6 | 0.5 | 3.2 | 1.4 | 9.5 |
| PCS (hPa)* | 80 | < 0.2 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| QSL2 | | | | | | | | | | |
| Parameter | N | Mean | Repeatability | | Between-Day | | Between-Run | | Total (Within-laboratory) | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| CT (sec) | 80 | 269.9 | 16.0 | 5.9 | 4.2 | 1.6 | 0.0 | 0.0 | 16.6 | 6.1 |
| CSL(%) | 80 | 99.9 | 0.6 | 0.6 | 0.0 | 0.0 | 0.0 | 0.0 | 0.6 | 0.6 |
| CS (hPa) | 80 | 4.6 | 0.4 | 8.5 | 0.2 | 3.8 | 0.0 | 0.0 | 0.4 | 9.3 |
| FCS (hPa) | 80 | 4.7 | 0.4 | 7.9 | 0.2 | 3.3 | 0.1 | 2.7 | 0.4 | 9.0 |
| PCS (hPa)* | 80 | < 0.2 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
*QStat control materials do not contain platelets.
b. Single-site precision with fibrinolysis positive controls
A second single-site precision study was performed over the course of 20 days, with two runs per day, and two replicates per run using two levels of fibrinolysis positive samples, In-House Fibrinolytic Control (IHFC) Level 1 and Level 2. A single Quantra Hemostasis Analyzer and a single lot of QStat Cartridges were utilized in the study, which was performed by a single operator. The IHFC Level 1 includes $85\mathrm{U / mL}$ tissue plasminogen activator (tPA; targeting a borderline CSL $(80 - 90\%)$ at or near the threshold), whereas the IHFC Level 2 includes $140\mathrm{U / mL}$ tPA (targeting a lysis positive CSL value $< 60\%$ and within the reportable range).
The results of this study demonstrated total $\% \mathrm{CV}$ for CT, CS, and FCS below $5.8\%$ across the two controls. For the CSL parameter, both the total $\% \mathrm{CV}$ and total standard deviation (SD) were evaluated, with results demonstrating $\% \mathrm{CV}$ of $7.1\%$ and SD of $10.2\%$ for the controls.
Single-site precision with fibrinolysis-positive controls results summary:
| IHFC Level 1 | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Parameter | N | Mean | Repeatability | | Between-Day | | Between-Run | | Total (Within-laboratory) | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| CT (sec) | 80 | 224.8 | 8.4 | 3.7 | 2.4 | 1.1 | 0.0 | 0.0 | 8.7 | 3.9 |
| CSL(%) | 80 | 82.2 | 5.6 | 6.8 | 1.5 | 1.9 | 0.0 | 0.0 | 5.8 | 7.1 |
| CS (hPa) | 80 | 20.2 | 0.8 | 3.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.8 | 3.9 |
| FCS (hPa) | 80 | 20.9 | 0.6 | 2.9 | 0.2 | 1.0 | 0.2 | 0.7 | 0.7 | 3.2 |
| PCS (hPa)* | 80 | < 0.2 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A |
K213917 - Page 10 of 25
{10}
| IHFC Level 2 | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Parameter | N | Mean | Repeatability | | Between-Day | | Between-Run | | Total (Within-laboratory) | | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | |
| CT (sec) | 80 | 219.8 | 11.6 | 5.3 | 12.7 | 5.8 | 5.3 | 2.4 | 12.7 | 5.8 | |
| CSL(%) | 80 | 29.6 | 10.0 | 33.6 | 0.0 | 0.0 | 2.1 | 7.0 | 10.2 | 34.4 | |
| CS (hPa) | 80 | 18.3 | 0.8 | 4.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.8 | 4.4 | |
| FCS (hPa) | 80 | 19.5 | 0.9 | 4.5 | 0.2 | 0.9 | 0.0 | 0.0 | 0.9 | 4.6 | |
| PCS (hPa)* | 80 | < 0.2 | N/A | N/A | N/A | N/A | N/A | N/A | N/A | N/A | |
*IHFC materials do not contain platelets.
c. Multi-site precision study:
The multi-site precision study was performed over the course of five days at three external locations representative of intended user locations; POC laboratory, clinical research laboratory, and blood gas laboratory servicing operating rooms. During each day of testing, each sample was tested in duplicate by one operator per site on two Quantra instruments in parallel (n=4 total replicates per sample panel per day).
Testing was conducted with a panel of three whole blood samples on a single cartridge lot. Samples were created daily including one native normal sample and two contrived samples to evaluate different levels of fibrinolysis at and below the CSL threshold. The multi-site precision study demonstrated total imprecision of CSL parameter $< 7\%$ CV and $< 10\%$ CV for CT, CS, PCS, and FCS for normal and low tPA concentration (at CSL threshold).
| All Sites – Sample 1 (unspiked) | | | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Parame ter | N | Mean | Repeatability | | Between-Day | | Between-Analyzer | | Within-Site | | Between-Site | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| CT | 60 | 148.7 | 5.5 | 3.7 | 3.4 | 2.3 | 0.0 | 0.0 | 1.5 | 1.0 | 2.4 | 1.6 | 7.1 | 4.8 |
| CSL | 60 | 98.4 | 1.3 | 1.4 | 0.2 | 0.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.2 | 0.2 | 1.4 | 1.4 |
| CS | 60 | 21.3 | 1.0 | 4.5 | 0.5 | 2.3 | 0.6 | 3.0 | 0.0 | 0.0 | 0.7 | 3.2 | 1.4 | 6.7 |
| PCS | 60 | 19.5 | 1.0 | 4.8 | 0.4 | 2.0 | 0.6 | 3.3 | 0.0 | 0.0 | 0.8 | 3.9 | 1.4 | 7.3 |
| FCS | 60 | 1.9 | 0.1 | 5.5 | 0.1 | 5.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 4.9 | 0.2 | 9.1 |
| All Sites – Sample 2 (tPA spiked to CSL threshold) | | | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Parame ter | N | Mean | Repeatability (Replicate) | | Between-Day | | Between-Analyzer | | Within-Site | | Between-Site | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| CT | 60 | 129.6 | 8.4 | 6.5 | 3.7 | 2.9 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 9.2 | 2.9 |
| CSL | 60 | 85.1 | 3.6 | 4.2 | 2.8 | 3.3 | 0.0 | 0.0 | 1.1 | 1.3 | 2.8 | 3.3 | 5.5 | 6.4 |
| CS | 60 | 14.0 | 0.7 | 4.9 | 0.2 | 1.7 | 0.4 | 2.4 | 0.3 | 2.3 | 0.3 | 2.1 | 0.9 | 6.6 |
| PCS | 60 | 12.8 | 0.7 | 5.4 | 0.2 | 1.8 | 0.4 | 2.8 | 0.3 | 2.5 | 0.4 | 2.8 | 0.9 | 7.4 |
| FCS | 60 | 1.2 | 0.1 | 6.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 6.8 | 0.1 | 9.2 |
K213917 - Page 11 of 25
{11}
| All Sites – Sample 3 (tPA spiked to below CSL threshold) | | | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Parame ter | N | Mean | Repeatability (Replicate) | | Between-Day | | Between-Analyzer | | Within-Site | | Between-Site | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| CT | 60 | 132.8 | 6.9 | 5.2 | 1.3 | 0.9 | 0.0 | 0.0 | 3.5 | 2.6 | 0.0 | 0.0 | 7.9 | 5.9 |
| CSL | 60 | 22.0 | 8.8 | 40.1 | 2.6 | 12.0 | 0.0 | 0.0 | 1.7 | 7.9 | 0.0 | 0.0 | 9.4 | 42.6 |
| CS | 60 | 24.4 | 1.4 | 5.6 | 0.2 | 0.7 | 0.7 | 2.9 | 0.0 | 0.0 | 0.7 | 2.9 | 1.7 | 6.9 |
| PCS | 60 | 22.3 | 1.3 | 6.0 | 0.2 | 1.0 | 0.7 | 3.3 | 0.7 | 3.4 | 0.0 | 0.0 | 1.7 | 7.7 |
| FCS | 60 | 2.1 | 0.2 | 9.9 | 0.0 | 0.0 | 0.0 | 0.9 | 0.0 | 0.0 | 0.1 | 2.3 | 0.2 | 10.2 |
d. Whole blood repeatability study:
The whole blood repeatability study was evaluated using whole blood samples across multiple instruments, operators, and cartridge lots. Four separate studies were conducted that included testing a total of 16 samples, four native and 12 contrived samples, types including the following: normal (unspiked), fibrinolytic (CSL values between 18.7% and 99.3%), and hypocoagulable samples.
Study #1 evaluated the single source of variance between paired cartridges and instruments. Testing included a panel of seven samples including two non-contrived apparently healthy donors, three contrived fibrinolytic, one native hypocoagulable, and one contrived direct oral anticoagulant (DOAC) hypocoagulable samples. All samples were tested in duplicate on three cartridge lots with three matched instruments by two operators within a single day.
Study #2 evaluated the single source of variance between paired operators and instruments. Testing included a panel of four contrived fibrinolytic samples across the CSL reportable range. All samples were tested in duplicate on two cartridge lots per instrument across three instruments matched with three operators within a single day.
Study #3 included testing with 12 instruments run in parallel to eliminate variability introduced by using multiple aliquots of tPA. The study included a panel of three contrived fibrinolytic samples across the CSL reportable range. All samples were tested without instrument replicates on six different instruments per operator with three cartridge lots. Testing was conducted by two operators with 12 different instruments in total within a single day and therefore, two replicates per lot per operator.
Study #4 included testing with 12 instruments run in parallel to eliminate variability introduced by sample stability limitations of DOAC-based hypocoagulable samples. The study included a panel of two samples: one native hypocoagulable sample and one contrived DOAC hypocoagulable sample. Both samples were tested in duplicate per lot per operator with two cartridge lots. Testing was conducted by three operators with four different instruments per operator for a total of 12 instruments within a single day.
Variance analysis was performed using 12 results obtained from each sample type across the four studies. The results demonstrated total %CV below 15% for CT, CS, FCS, and
K213917 - Page 12 of 25
{12}
PCS across all sample types. For the CSL parameter, both the total %CV and total standard deviation (SD) were evaluated. The CSL %CV results were below 15% or SD below 12% across the various sample types and are summarized in the table below.
| Whole Blood Repeatability Testing Summary: CSL | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 1 | | | | | | | | | | | | |
| Sample ID | N | Mean | Between - Replicate | | Between- Operator | | Between - Instrument/ Cartridge Lot | | Interaction Operator (Instrument /Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Normal WB | 12 | 99.3 | 1.0 | 1.0 | 0.5 | 0.5 | 0.0 | 0.0 | 0.0 | 0.0 | 1.2 | 1.2 |
| Normal WB | 12 | 98.8 | 1.4 | 1.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.8 | 0.8 | 1.6 | 1.6 |
| 42 U/mL tPA | 12 | 73.8 | 7.9 | 10.7 | 0.0 | 0.0 | 3.3 | 4.5 | 0.0 | 0.0 | 8.6 | 11.6 |
| 42.5 U/mL tPA | 12 | 92.2 | 2.3 | 2.5 | 2.7 | 2.9 | 1.3 | 1.4 | 0.0 | 0.0 | 3.8 | 4.1 |
| 60 U/mL tPA | 12 | 45.4 | 10.5 | 23.1 | 0.0 | 0.0 | 0.0 | 0.0 | 5.5 | 12.0 | 11.8 | 26.1 |
| Apixaban 5 mg bidaily | 12 | 97.8 | 2.5 | 2.5 | 0.0 | 0.0 | 0.0 | 0.0 | 4.4 | 4.5 | 5.1 | 5.2 |
| Rivaroxaban 80 ng/mL | 12 | 98.8 | 2.2 | 2.2 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 2.2 | 2.2 |
| | Whole Blood Repeatability Testing Summary: CSL | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 2 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- (Operator/ Instrument) | | Between- Cartridge Lot | | Interaction (Operator/ Instrument) Cartridge Lot | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 22.5 U/mL tPA | 12 | 75.6 | 7.5 | 10.0 | 3.2 | 4.2 | 2.4 | 3.2 | 0.0 | 0.0 | 8.5 | 11.3 |
| 35 U/mL tPA | 12 | 95.8 | 2.2 | 2.3 | 1.5 | 1.6 | 0.0 | 0.0 | 1.2 | 1.2 | 2.9 | 3.1 |
| 40 U/mL tPA | 12 | 75.8 | 5.7 | 7.5 | 0.0 | 0.0 | 0.0 | 0.0 | 8.9 | 11.7 | 10.5 | 13.9 |
| 50 U/mL tPA | 12 | 51.1 | 8.0 | 15.6 | 0.0 | 0.0 | 0.0 | 0.0 | 4.2 | 8.3 | 9.0 | 17.7 |
| Whole Blood Repeatability Testing Summary: CSL | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 3 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 30 U/mL tPA | 12 | 80.3 | 5.4 | 6.8 | 0.0 | 0.0 | 0.0 | 0.0 | 4.3 | 5.3 | 6.9 | 8.6 |
| 60 U/mL tPA | 12 | 65.3 | 8.7 | 13.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 8.7 | 13.3 |
| 80 U/mL tPA | 12 | 18.7 | 5.5 | 29.7 | 3.6 | 19.4 | 6.5 | 34.9 | 0.0 | 0.0 | 9.3 | 49.7 |
| | Whole Blood Repeatability Testing Summary: CSL | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 4 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Rivaroxaban 20 ng/mL | 12 | 99.3 | 1.0 | 1.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.0 | 1.0 |
| Dabigatran 300 ng/mL | 12 | 98.3 | 1.7 | 1.8 | 0.0 | 0.0 | 0.0 | 0.0 | 1.5 | 1.5 | 2.3 | 2.3 |
K213917 - Page 13 of 25
{13}
K213917 - Page 14 of 25
| Whole Blood Repeatability Testing Summary: CT | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 1 | | | | | | | | | | | | |
| Sample ID | N | Mean | Between - Replicate | | Between- Operator | | Between - Instrument/ Cartridge Lot | | Interaction Operator (Instrument /Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Normal WB | 12 | 154.2 | 4.3 | 2.8 | 1.1 | 0.7 | 5.4 | 3.5 | 0.0 | 0.0 | 7.0 | 4.5 |
| Normal WB | 12 | 123.8 | 6.8 | 5.5 | 0.0 | 0.0 | 2.0 | 1.6 | 0.0 | 0.0 | 7.1 | 5.8 |
| 42 U/mL tPA | 12 | 148.6 | 8.1 | 5.5 | 0.0 | 0.0 | 4.0 | 2.7 | 0.0 | 0.0 | 9.1 | 6.1 |
| 42.5 U/mL tPA | 12 | 137.6 | 5.5 | 4.0 | 6.8 | 5.0 | 5.5 | 4.0 | 0.0 | 0.0 | 10.3 | 7.5 |
| 60 U/mL tPA | 12 | 155.2 | 11.6 | 7.5 | 3.1 | 2.0 | 2.9 | 1.8 | 0.0 | 0.0 | 12.3 | 8.0 |
| Apixaban 5 mg bidaily | 12 | 147.2 | 8.2 | 5.6 | 4.9 | 3.3 | 1.3 | 0.9 | 0.0 | 0.0 | 9.7 | 6.6 |
| Rivaroxaban 80 ng/mL | 12 | 191.5 | 9.7 | 5.1 | 2.2 | 1.1 | 0.0 | 0.0 | 1.8 | 0.9 | 10.1 | 5.3 |
| Whole Blood Repeatability Testing Summary: CT | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 2 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator/ Instrument) | | Between- Cartridge Lot | | Interaction (Operator/ Instrument) Cartridge Lot | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 22.5 U/mL tPA | 12 | 142.7 | 8.5 | 6.0 | 0.9 | 0.7 | 2.3 | 1.6 | 0.0 | 0.0 | 8.9 | 6.2 |
| 35 U/mL tPA | 12 | 140.7 | 9.9 | 7.1 | 4.9 | 3.5 | 0.0 | 0.0 | 0.0 | 0.0 | 11.1 | 7.9 |
| 40 U/mL tPA | 12 | 128.8 | 4.7 | 3.6 | 2.4 | 1.9 | 0.0 | 0.0 | 4.0 | 3.1 | 6.6 | 5.1 |
| 50 U/mL tPA | 12 | 157.2 | 8.1 | 5.1 | 0.0 | 0.0 | 0.0 | 0.0 | 5.3 | 3.4 | 9.7 | 6.1 |
| Whole Blood Repeatability Testing Summary: CT | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 3 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 30 U/mL tPA | 12 | 108.2 | 10.7 | 9.9 | 0.0 | 0.0 | 0.0 | 0.0 | 11.8 | 10.9 | 15.9 | 14.7 |
| 60 U/mL tPA | 12 | 131.7 | 6.0 | 4.5 | 0.0 | 0.0 | 0.0 | 0.0 | 3.8 | 2.9 | 7.1 | 5.4 |
| 80 U/mL tPA | 12 | 133.8 | 7.5 | 5.6 | 0.0 | 0.0 | 2.5 | 1.8 | 0.0 | 0.0 | 7.9 | 5.9 |
| Whole Blood Repeatability Testing Summary: CT | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 4 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Rivaroxaban 20 ng/mL | 12 | 224.1 | 7.6 | 3.4 | 15.8 | 7.0 | 5.8 | 2.6 | 0.0 | 0.0 | 18.5 | 8.2 |
{14}
| Dabigatran 300 ng/mL | 12 | 251.8 | 7.5 | 3.0 | 0.0 | 0.0 | 0.0 | 8.0 | 3.2 | 11.0 | 4.4 |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Whole Blood Repeatability Testing Summary: CS | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 1 | | | | | | | | | | | | |
| Sample ID | N | Mean | Between - Replicate | | Between- Operator | | Between - Instrument/C artridge Lot | | Interaction Operator (Instrument /Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Normal WB | 12 | 23.9 | 1.0 | 4.4 | 0.8 | 3.5 | 1.1 | 4.4 | 0.2 | 0.9 | 1.7 | 7.1 |
| Normal WB | 12 | 10.8 | 0.6 | 5.5 | 0.3 | 2.5 | 0.3 | 2.8 | 0.0 | 0.0 | 0.7 | 6.6 |
| 42 U/mL tPA | 12 | 22.8 | 1.4 | 6.9 | 0.8 | 3.4 | 0.2 | 0.7 | 0.0 | 0.0 | 1.6 | 7.8 |
| 42.5 U/mL tPA | 12 | 26.1 | 1.2 | 4.5 | 0.0 | 0.0 | 2.4 | 9.0 | 0.7 | 2.5 | 2.7 | 10.4 |
| 60 U/mL tPA | 12 | 15.4 | 0.8 | 5.4 | 0.3 | 1.6 | 0.8 | 5.1 | 0.3 | 2.2 | 1.2 | 7.9 |
| Apixaban 5 mg bidaily | 12 | 14.2 | 1.0 | 6.9 | 0.0 | 0.0 | 0.0 | 0.0 | 1.7 | 11.7 | 1.9 | 13.6 |
| Rivaroxaban 80 ng/mL | 12 | 15.0 | 1.3 | 8.8 | 0.0 | 0.0 | 0.4 | 2.5 | 0.6 | 3.7 | 1.5 | 9.8 |
| | Whole Blood Repeatability Testing Summary: CS | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 2 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator/ Instrument) | | Between- Cartridge Lot | | Interaction (Operator/ Instrument) Cartridge Lot | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 22.5 U/mL tPA | 12 | 19.9 | 0.8 | 4.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.8 | 4.2 | 1.2 | 5.8 |
| 35 U/mL tPA | 12 | 21.3 | 1.0 | 4.6 | 0.4 | 1.6 | 1.0 | 4.9 | 0.3 | 1.2 | 1.5 | 7.0 |
| 40 U/mL tPA | 12 | 14.4 | 0.5 | 3.3 | 0.7 | 4.5 | 0.6 | 3.9 | 0.6 | 3.9 | 1.1 | 7.8 |
| 50 U/mL tPA | 12 | 25.8 | 1.0 | 3.7 | 0.5 | 1.8 | 0.1 | 0.2 | 0.0 | 0.0 | 1.1 | 4.2 |
| Whole Blood Repeatability Testing Summary: CS | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 3 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 30 U/mL tPA | 12 | 10.9 | 0.3 | 2.8 | 0.0 | 0.0 | 0.2 | 2.0 | 0.5 | 4.9 | 0.7 | 6.0 |
| 60 U/mL tPA | 12 | 26.5 | 2.2 | 8.3 | 0.0 | 0.0 | 0.0 | 0.0 | 1.8 | 6.9 | 2.9 | 10.8 |
| 80 U/mL tPA | 12 | 20.5 | 1.4 | 6.8 | 0.0 | 0.0 | 1.5 | 7.3 | 0.0 | 0.0 | 2.1 | 10.0 |
| | Whole Blood Repeatability Testing Summary: CS | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 4 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Rivaroxaban 20 ng/mL | 12 | 19.2 | 6.0 | 31.1 | 0.0 | 0.0 | 2.1 | 11.1 | 1.9 | 10.0 | 6.6 | 34.5 |
| Dabigatran 300 ng/mL | 12 | 14.2 | 1.0 | 6.7 | 0.3 | 2.1 | 0.4 | 2.5 | 0.0 | 0.0 | 1.1 | 7.5 |
K213917 - Page 15 of 25
{15}
K213917 - Page 16 of 25
| Whole Blood Repeatability Testing Summary: FCS | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 1 | | | | | | | | | | | | |
| Sample ID | N | Mean | Between - Replicate | | Between- Operator | | Between - Instrument/ Cartridge Lot | | Interaction Operator (Instrument /Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Normal WB | 12 | 2.3 | 0.1 | 3.3 | 0.0 | 1.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 3.5 |
| Normal WB | 12 | 0.8 | 0.1 | 3.6 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 3.6 |
| 42 U/mL tPA | 12 | 2.1 | 0.1 | 3.4 | 0.0 | 1.0 | 0.1 | 3.4 | 0.1 | 2.6 | 0.1 | 5.6 |
| 42.5 U/mL tPA | 12 | 2.7 | 0.2 | 6.5 | 0.1 | 4.2 | 0.1 | 2.6 | 0.0 | 0.0 | 0.2 | 8.2 |
| 60 U/mL tPA | 12 | 1.1 | 0.0 | 2.6 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 4.6 | 0.1 | 5.3 |
| Apixaban 5mg bidaily | 12 | 1.7 | 0.1 | 6.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 5.9 | 0.2 | 8.8 |
| Rivaroxaban 80 ng/mL | 12 | 1.3 | 0.1 | 3.8 | 0.0 | 3.1 | 0.1 | 6.0 | 0.0 | 1.5 | 0.1 | 7.9 |
| | Whole Blood Repeatability Testing Summary: FCS | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 2 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator/ Instrument) | | Between- Cartridge Lot | | Interaction (Operator/ Instrument) Cartridge Lot | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 22.5 U/mL tPA | 12 | 2.4 | 0.2 | 7.6 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 3.3 | 0.2 | 8.3 |
| 35 U/mL tPA | 12 | 2.3 | 0.1 | 2.8 | 0.1 | 3.1 | 0.0 | 0.0 | 0.0 | 1.3 | 0.1 | 4.4 |
| 40 U/mL tPA | 12 | 1.4 | 0.1 | 4.9 | 0.0 | 2.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 5.3 |
| 50 U/mL tPA | 12 | 2.5 | 0.1 | 5.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.1 | 5.4 |
| Whole Blood Repeatability Testing Summary: FCS | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 3 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 30 U/mL tPA | 12 | 0.6 | 0.0 | 4.5 | 0.0 | 0.0 | 0.1 | 7.8 | 0.0 | 0.0 | 0.1 | 9.0 |
| 60 U/mL tPA | 12 | 2.9 | 0.3 | 11.8 | 0.1 | 4.3 | 0.1 | 3.7 | 0.0 | 0.0 | 0.4 | 13.1 |
| 80 U/mL tPA | 12 | 1.9 | 0.2 | 7.9 | 0.0 | 0.0 | 0.1 | 2.6 | 0.0 | 0.0 | 0.2 | 8.4 |
| | Whole Blood Repeatability Testing Summary: FCS | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 4 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Rivaroxaban 20 ng/mL | 12 | 2.3 | 0.4 | 16.1 | 0.3 | 12.7 | 0.0 | 0.0 | 0.1 | 4.2 | 0.5 | 20.9 |
| Dabigatran 300 ng/mL | 12 | 1.3 | 0.1 | 4.6 | 0.0 | 7.1 | 0.0 | 0.0 | 0.0 | 2.8 | 0.1 | 8.9 |
{16}
K213917 - Page 17 of 25
| Whole Blood Repeatability Testing Summary: PCS | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 1 | | | | | | | | | | | | |
| Sample ID | N | Mean | Between - Replicate | | Between- Operator | | Between - Instrument/ Cartridge Lot | | Interaction Operator (Instrument /Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Normal WB | 12 | 21.5 | 0.9 | 4.4 | 0.8 | 3.8 | 1.1 | 5.0 | 0.3 | 1.2 | 1.7 | 7.7 |
| Normal WB | 12 | 10.0 | 0.6 | 5.9 | 0.3 | 2.6 | 0.3 | 3.1 | 0.0 | 0.0 | 0.7 | 7.1 |
| 42 U/mL tPA | 12 | 20.7 | 1.4 | 6.9 | 0.7 | 3.4 | 0.3 | 1.3 | 0.0 | 0.0 | 1.6 | 7.8 |
| 42.5 U/mL tPA | 12 | 23.3 | 1.3 | 5.4 | 0.0 | 0.0 | 2.4 | 10.4 | 0.5 | 2.3 | 2.8 | 11.9 |
| 60 U/mL tPA | 12 | 14.3 | 0.8 | 5.8 | 0.3 | 1.9 | 0.8 | 5.7 | 0.3 | 2.3 | 1.2 | 8.6 |
| Apixaban 5 mg bidaily | 12 | 12.5 | 1.0 | 8.1 | 0.0 | 0.0 | 0.0 | 0.0 | 1.5 | 12.2 | 1.8 | 14.6 |
| Rivaroxaban 80 ng/mL | 12 | 13.7 | 1.3 | 9.7 | 0.0 | 0.0 | 0.5 | 4.0 | 0.5 | 3.3 | 1.5 | 11.0 |
| Whole Blood Repeatability Testing Summary: PCS | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 2 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator/ Instrument) | | Between- Cartridge Lot | | Interaction (Operator/ Instrument) Cartridge Lot | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 22.5 U/mL tPA | 12 | 17.5 | 0.8 | 4.4 | 0.0 | 0.0 | 0.0 | 0.0 | 0.7 | 4.0 | 1.0 | 5.9 |
| 35 U/mL tPA | 12 | 19.0 | 1.0 | 5.1 | 0.4 | 2.3 | 1.0 | 5.4 | 0.3 | 1.6 | 1.5 | 7.9 |
| 40 U/mL tPA | 12 | 13.0 | 0.5 | 4.0 | 0.6 | 4.8 | 0.6 | 4.3 | 0.6 | 4.2 | 1.1 | 8.6 |
| 50 U/mL tPA | 12 | 23.3 | 0.9 | 4.1 | 0.5 | 1.9 | 0.1 | 0.5 | 0.0 | 0.0 | 1.1 | 4.5 |
| Whole Blood Repeatability Testing Summary: PCS | | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 3 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| 30 U/mL tPA | 12 | 10.2 | 0.3 | 2.9 | 0.1 | 1.1 | 0.3 | 3.0 | 0.5 | 5.1 | 0.7 | 6.7 |
| 60 U/mL tPA | 12 | 23.6 | 2.1 | 8.8 | 0.0 | 0.0 | 0.0 | 0.0 | 2.2 | 9.2 | 3.0 | 12.8 |
| 80 U/mL tPA | 12 | 18.6 | 1.4 | 7.7 | 0.0 | 0.0 | 1.5 | 7.8 | 0.0 | 0.0 | 2.0 | 11.0 |
| | Whole Blood Repeatability Testing Summary: PCS | | | | | | | | | | | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| Study 4 | | | | | | | | | | | | |
| Parameter | N | Mean | Between - Replicate | | Between- Operator | | Between- Cartridge Lot | | Interaction Operator (Cartridge Lot) | | Total | |
| | | | SD | %CV | SD | %CV | SD | %CV | SD | %CV | SD | %CV |
| Rivaroxaban 20 ng/mL | 12 | 16.9 | 5.7 | 34.0 | 0.0 | 0.0 | 2.1 | 12.6 | 2.3 | 13.5 | 6.5 | 38.7 |
| Dabigatran 300 ng/mL | 12 | 12.9 | 1.0 | 7.4 | 0.2 | 1.5 | 0.4 | 2.9 | 0.0 | 0.0 | 1.0 | 8.1 |
{17}
K213917 - Page 18 of 25
2. Linearity:
To assess the correlation between the QStat CSL parameter and tissue plasminogen activator (tPA) concentrations across the entire CSL reportable range, a dose-response study was performed. Five subjects were enrolled in the tPA dose-response study. For each enrolled subject, tPA was added to citrated whole blood samples to achieve final tPA concentrations of 0, 10, 30, 50, and 100 U/mL. Samples were tested in duplicate with the Quantra QStat Cartridge. A linear relationship was demonstrated between CSL and tPA concentrations.
3. Analytical Specificity/Interference:
The interference study evaluated the effect of potential interfering substances with normal whole blood and hypocoagulable tPA-treated whole blood. Each endogenous interferent was tested with normal whole blood and hypocoagulable tPA-treated whole blood.
Hypocoagulable specimens tested in the endogenous interference study consisted of:
- Fibrinolytic specimens (tPA-treated whole blood)
- Fibrinolytic specimens with additional hypocoagulable characteristics
- abciximab & tPA-treated whole blood
- tPA-treated low fibrinogen donor blood
If no interference was observed for normal whole blood and the three hypocoagulable specimen types an analyte was considered to not interfere up to the highest level tested, then no additional testing was performed.
The following table shows the highest concentration at which each substance showed no significant interference in whole blood samples collected in 3.2% sodium citrate anticoagulant collection tubes.
| Potential Interferent | Concentration |
| --- | --- |
| Triglycerides / Lipid | 1335 mg/dL |
| Hemoglobin | 200 mg/dL |
| Hemolysis | Interfered at all levels tested (≥0.02 g/dL) |
| Lupus Anticoagulant | Interfered at all levels tested (≥20%) |
| Clopidogrel | 300 μM |
| Salicylic Acid (Aspirin) | 4.34 mM (69.4 mg/dL) |
| Protamine sulfate | 20 μg/mL |
| Tranexamic acid (TXA) | Normal blood: 60 μg/mL
Hypocoagulable tPA-treated blood: 1 μg/mL |
| Clopidogrel (2-MeSAMP) | 300 μM |
| Protamine sulfate | Normal blood: 20 μg/mL
Hypocoagulable tPA-treated blood: 50 μg/mL |
| EACA | 600 μg/mL
Hypocoagulable tPA-treated blood: 10 μg/mL |
| MPA | 21 μg/mL
Hypocoagulable tPA-treated blood: 7 μg/mL |
| Tacrolimus | 144 ng/mL |
| Prednisone | 99 ng/mL |
{18}
K213917 - Page 19 of 25
| Potential Interferent | Concentration |
| --- | --- |
| Rifaximin | 40.5 ng/mL |
| Lactulose | 12 μg/mL |
| Hemodilution
(0–50% dilution with saline) | >10% |
| Dabigatran (Pradaxa) | 25 ng/mL |
| Rivaroxaban (Xarelto) | 25 ng/mL |
| Hematocrit | Normal whole blood (15.4–47.8% HCT): CT, CS, PCS, and FCS decreased with increasing hematocrit. No hematocrit interference occurred for CSL.
Hypocoagulable whole blood (13. –55.3% HCT): CT, CS, PCS, and FCS decreased with increasing hematocrit. CSL increased with increasing hematocrit. |
## Sample Variable Interferences
Potential sources of interference due to sample collection variables were tested at one or more sample variable levels and compared to the control condition. The following potential sources of variability related to samples and sample preparation were evaluated: testing of first collected tube (discard tube) and under-filled tube (short draw).
## Discard Tube:
The effect of omitting an initial discard tube (70–95% normal volume) was evaluated by comparing results from an initial discard tube to results from a subsequent normal sample tube using Beckon Dickinson (BD) 2.7 mL tube. Discard tubes caused interference in CT, CS, PCS, and FCS relative to subsequent adequately filled sample tubes. Differences in results was noted between 0–18% in 9% of CS, PCS, and FCS results and 0–20% of 17% of CT results.
## Short Draw/Under-filled Tube:
The effect of a short draw on the blood collection tube was evaluated by testing underfilled collection tubes at four levels ranging from 60%–90% of a typical tube fill. Collection of normal whole blood into the collection tubes was interrupted during the fill process to give tubes that were underfilled at 60%–90% of the specified normal fill and one tube filled to 100%. Testing was performed separately for 2.7 mL and 4.5 mL Becton Dickinson (BD) Vacutainer tubes (3.2% citrate). Short draw was found to interfere with QStat parameters at fill levels ≤ 80% in BD 2.7 mL tubes and ≤70% for the BD 4.5 mL tubes. Tests for which incomplete filling of the cartridge occurred due to insufficient sample volume (≤70% fill volume in 2.7 mL BD Vacutainer) triggered one or more internal quality control checks, resulting in no reported value.
## 4. Assay Reportable Range:
Validation that the QStat Cartridge parameters demonstrate functional performance across the claimed reportable ranges for each parameter was supported by data from the clinical validation study.
| Output Parameter | Units | Reportable Ranges |
| --- | --- | --- |
| Clot Time (CT) | Seconds | 60 – 480 |
{19}
| Output Parameter | Units | Reportable Ranges |
| --- | --- | --- |
| Clot Stability to Lysis (CSL) | Percent | 10 – 100 |
| Clot Stiffness (CS) | hectoPascals | 2 – 65 |
| Platelet Contribution to Clot Stiffness (PCS) | hectoPascals | 2 – 50 |
| Fibrinogen Contribution to Clot Stiffness (FCS) | hectoPascals | 0.2 -30 |
5. Traceability, Stability, Expected Values (Controls, Calibrators, or Methods):
Shelf-Life Cartridge Stability
The shelf-life reagent stability study includes three QStat Cartridge lots stored at 28°C (room temperature) and 2–8°C (refrigerated) with two levels of controls (QSL1 and QSL2), unspiked donor whole blood, and donor whole blood spiked with 100 IU/mL tPA.
The cartridges were tested at time zero (T0) and every subsequent month up to 18 months. Shelf-life cartridge stability studies concluded unopened QStat Cartridge pouches can be stored up to 17 months after the date of manufacture at 2–28°C.
In-Use Reagent Stability
Cartridges are intended to be used shortly after opening (the foil pouch package), however a study was conducted to determine the stability of QStat Cartridge parameter measurements after the cartridge was opened compared to measurements from time 0, baseline measurement. Samples evaluated in this study were from the same whole blood donor tested in duplicate at 75% relative humidity and approximately 22°C. Results concluded QStat Cartridges are to be used within 15 minutes of opening.
Sample Stability
A sample stability study evaluated the stability of citrated whole blood for testing with the QStat Cartridge at ambient conditions (20–22°C) and in an incubator (28°C). A total of 17 native and contrived citrated whole blood specimens were evaluated for sample stability including normal whole blood as well as fibrinolytic and hypocoagulable whole blood samples. All sample types were tested at baseline (T0) and at intervals of 0.5, 1, 2, 4, and 5 hours after drawing. The study result supports the whole blood specimen stability is two hours after collection at 20–28°C.
Quality Control:
The Quantra Analyzer performs internal QC checks of all system components at regular intervals and during each phase of a test run on a cartridge to verify that the instrument hardware and all subsystems are functioning properly. There is no calibration material for the Quantra Hemostasis Analyzer, as user calibration is not required.
There are two levels of external QStat Controls – Level 1 (QSL1) and Level 2 (QSL2). The QStat Controls contain materials to test the measured output parameters for the QStat Cartridge: Clot Time (CT), Clot Stiffness (CS), and Fibrinogen Contribution to Clot Stiffness (FCS), as well as the calculated parameters, Clot Stability to Lysis (CSL), and Platelet Contribution to Clot Stiffness (PCS). The QSL1 and QSL2 do not include platelets; therefore, values for the CS parameter are expected to be at or below the reportable range (< 2 hPa). Value Assignment cards included in each control kit will provide the lot-specific
K213917 - Page 20 of 25
{20}
target ranges for the five Quantra output parameters. The Value Assignment is done by HemoSonics' procedure, as no standardized reference materials for the Quantra exist.
QSL1 and QSL2 vials are single-use only and should be stored refrigerated 2–8°C until use. When stored refrigerated, QSL1 and QSL2, should be allowed to warm to room temperature for at least 30 minutes before reconstituting.
QStat Quality Controls are recommended for use when changing QStat Cartridge lots, changing control lots, or after significant changes are made to the Quantra Hemostasis Analyzer.
## Quality Control In-Use (Reconstituted) Stability Study
Reconstituted stability studies for QStat QC were evaluated using three lots of QSL1 and QSL2 and four lots of QStat Cartridges. Lyophilized QC lots were reconstituted following the instructions provided in the Instructions For Use for QStat controls. Controls were allowed to sit at room temperature during the 30-minute reconstitution time and during the study. Reconstituted controls were tested at baseline (30 minutes after reconstitution), and at time intervals for up to at least 2 hours after reconstitution. The in-use stability regression analysis supports the stability conclusions for QStat Level 1 and Level 2 Controls, for a minimum of 2 hours reconstituted stability at room temperature.
## Quality Control Shelf-Life Stability Study
Three lots of QStat QC were evaluated to establish the shelf-life stability of the lyophilized QStat Quality Control materials when stored at 2–8°C. QC was tested at Time 0 and every subsequent month for a minimum of 13 months. When stored at 2–8°C, QStat Level 1 and 2 Controls are stable for 12 months.
6. Detection Limit:
Not applicable.
7. Assay Cut-Off:
Not applicable.
B. Comparison Studies:
1. Method Comparison with Predicate Device:
a. Comparison with ROTEM delta Thromboelastometry System:
The clinical performance of the QStat Cartridge and the predicate device, ROTEM delta Thromboelastometry System, was evaluated in a multi-center prospective observational study across 13 clinical sites in the US involving subjects 18 years of age or older. The study included 125 patients undergoing a liver transplant surgery, 159 trauma patients experiencing injuries requiring a full trauma response, and five normal subjects from which contrived samples were prepared.
From subjects undergoing liver transplant, a minimum of three blood samples were collected at the following times for analysis on the QStat Cartridge and the ROTEM®
K213917 - Page 21 of 25
{21}
delta Thromboelastometry System: before surgery, during the anhepatic phase, and post-reperfusion. For trauma subjects, at least one blood sample was collected in the emergency room, the operating room, or the intensive care unit at the time of admission, during acute hemorrhage and transfusion of blood products, or 24 to 48 hours after arrival at the trauma unit to assess potential hypercoagulability. Contrived samples (6.7%) were prepared by spiking blood samples from normal volunteers with fibrinogen and tPA to broaden the range of measurements for CS, FCS and CSL. All blood samples were run in parallel on the Quantra QStat Cartridge and the ROTEM delta.
Correlation and clinical agreement analyses were performed to compare measurements obtained with the QStat Cartridge to comparable measures obtained with the ROTEM delta Thromboelastometry System. A linear regression analysis was performed to evaluate the correlation between the QStat parameters and comparable ROTEM delta Thromboelastometry System parameters. For the primary analysis, samples from liver transplant and trauma subjects were combined with contrived samples. The results met the pre-defined acceptance criteria.
| | N | Sample Range | Slope Estimate (95% CI) | Intercept Estimate (95% CI) | Correlation Coefficients | |
| --- | --- | --- | --- | --- | --- | --- |
| | | | | | Pearson (95% CI) | Spearman (95% CI) |
| CT vs INTEM CT | 448 | 66–479 | 0.37 (0.35, 0.39) | 75.51 (69.90, 81.11) | 0.89 (0.87, 0.91) | 0.86 (0.83, 0.88) |
| CS vs EXTEM A20 | 540 | 2–52 | 2.84 (2.74, 2.94) | -1.46 (-2.14, -0.78) | 0.92 (0.91, 0.93) | 0.91 (0.90, 0.93) |
| FCS vs FIBTEM A20 | 539 | 0.2–12.9 | 3.08 (2.95, 3.21) | -0.30 (-0.45, -0.15) | 0.89 (0.87, 0.91) | 0.87 (0.85, 0.89) |
| PCS vs PLATEM | 513 | 2.0–39.2 | 2.75 (2.43, 2.71) | 0.33 (-0.45, 1.11) | 0.93 (0.92, 0.94) | 0.93 (0.92, 0.94) |
A clinical agreement analysis was performed to evaluate the ability of the QStat CSL parameter to identify fibrinolytic samples relative to the comparable ROTEM® delta Thromboelastometry System lysis parameter EXTEM ML. The overall agreement of patient sample assignments into lysis-positive and lysis-negative based on data for QStat CSL and ROTEM delta EXTEM ML was 92.6%. Agreement within the lysis-positive and lysis-negative subcategories was 90.2% and 93.2%, respectively. These results met the acceptance criteria for overall and subcategory agreements.
Clinical Agreement Analysis for Comparison of QStat and ROTEM delta Lysis Parameters
| ROTEM delta EXTEM ML | | | | |
| --- | --- | --- | --- | --- |
| QUANTRA QStat CSL | | Lysis Positive* | Lysis Negative* | Total |
| | Lysis Positive** | 83 | 28 | 111 |
| | Lysis Negative** | 9 | 381 | 390 |
| | Total | 92 | 409 | 501 |
**Classification based on Quantra definition of lysis
* Classification based on ROTEM definitions of lysis
Summary Metrics for Clinical Agreement Analysis for Comparison of QStat and ROTEM delta Lysis Parameters
K213917 - Page 22 of 25
{22}
| Category | Agreement (95% CI) |
| --- | --- |
| Lysis Positive | 0.90 (0.82, 0.95) |
| Lysis Negative | 0.93 (0.93, 0.95) |
| Overall | 0.93 (0.90, 0.95) |
# Linear Regression Summary: Liver Transplant Subjects
Eligible Liver Transplant Subject Set with 24 randomly selected Contrived Samples
| | N | Sample Range | Slope Estimate (95% CI) | Intercept Estimate (95% CI) | Correlation Coefficients | |
| --- | --- | --- | --- | --- | --- | --- |
| | | | | | Pearson (95% CI) | Spearman (95% CI) |
| CT vs INTEM CT | 316 | 66–479 | 0.36 (0.37, 0.38) | 85.52 (78.12, 92.92) | 0.90 (0.86, 0.91) | 0.85 (0.81, 0.88) |
| CS vs EXTEM A20 | 395 | 2–48.6 | 3.18 (3.08, 3.28) | -2.49 (-3.08, -1.91) | 0.95 (0.94, 0.96) | 0.91 (0.90, 0.93) |
| FCS vs FIBTEM A20 | 403 | 0.3–12.1 | 3.30 (3.16, 3.45) | -0.34 (-0.49, -0.19) | 0.91 (0.89, 0.93) | 0.88 (0.86, 0.90) |
| PCS vs PLATEM | 374 | 2.1–36.5 | 2.97 (2.86, 3.08) | -1.30 (-1.83, -0.77) | 0.94 (0.93, 0.95) | 0.91 (0.89, 0.93) |
# Linear Regression Summary: Trauma Subjects
Eligible Trauma Subject Set with 12 randomly selected Contrived Samples
| | N | Sample Range | Slope Estimate (95% CI) | Intercept Estimate (95% CI) | Correlation Coefficients | |
| --- | --- | --- | --- | --- | --- | --- |
| | | | | | Pearson (95% CI) | Spearman (95% CI) |
| CT vs INTEM CT | 163 | 68–273 | 0.58 (0.51, 0.65) | 29.29 (17.69, 40.90) | 0.80 (0.77, 0.83) | 0.78 (0.76, 0.79) |
| CS vs EXTEM A20 | 144 | 2.4–52 | 2.82 (2.55, 3.08) | -2.85 (-5.02, -0.67) | 0.87 (0.83, 0.91) | 0.89 (0.85, 0.92) |
| FCS vs FIBTEM A20 | 142 | 0.2–9.7 | 3.18 (2.90, 3.46) | -0.72 (-1.07, -0.38) | 0.88 (0.84, 0.91) | 0.84 (0.79, 0.88) |
| PCS vs PLATEM | 139 | 2.0–37.1 | 2.61 (2.36, 2.87) | -0.92 (-2.78, 0.95) | 0.86 (0.81, 0.90) | 0.89 (0.85, 0.92) |
# b. Comparison with the TEG 6S Hemostasis System (K183160)
At two clinical sites, 52 samples from trauma subjects were analyzed on the QStat Cartridge and the TEG 6S Hemostasis System. For the correlation analysis, TEG 6S clot stiffness amplitudes were first converted to units of clot elasticity (hPa). The limited data set was not supplemented with contrived samples.
| | N | Sample Range | Slope Estimate (95% CI) | Intercept Estimate (95% CI) | Correlation Coefficients | |
| --- | --- | --- | --- | --- | --- | --- |
| | | | | | Pearson (95% CI) | Spearman (95% CI) |
| CT vs CK-R | 28 | 68–239 | 15.45 (12.15, 18.75) | 46.49 (28.34, 64.64) | 0.80 (0.67, 0.88) | 0.81 (0.69, 0.88) |
| CS vs CK-MA | 26 | 2.6–34.4 | 0.03 (0.03, 0.04) | -6.68 (-10.23, -3.78) | 0.95 (0.88, 0.98) | 0.93 (0.84, 0.97) |
| CS vs CRT-MA | 26 | 2.0–30.4 | 0.03 (0.03, 0.04) | -7.01 (-9.74, -3.61) | 0.95 (0.89, 0.98) | 0.92 (0.83, 0.97) |
K213917 - Page 23 of 25
{23}
| FCS vs CFF-MA | 26 | 0.2–4.0 | 0.13
(0.09, 0.17) | 0.66
(-1.35 – 0.29) | 0.82
(0.63, 0.92) | 0.89
(0.78, 0.95) |
| --- | --- | --- | --- | --- | --- | --- |
Clinical Agreement Analysis for Comparison of QStat Cartridge CSL and TEG 6S LY30
| | | TEG6S LY30 | | |
| --- | --- | --- | --- | --- |
| QUANTRA
QStat®
CSL | | Lysis Positive* | Lysis Negative* | Total |
| | Lysis Positive** | 1 | 0 | 1 |
| | Lysis Negative** | 2 | 21 | 23 |
| | Total | 3 | 21 | 24 |
**Classification based on TEG6S definition of lysis (Lysis Positive if LY30 was > 2.6%)
* Classification based on ROTEM definitions of lysis
Overall, the agreement between QStat CSL and TEG 6S LY30 was 91.7% (with 95% CI of 0.73, 0.99).
2. Matrix Comparison:
Not applicable
C. Clinical Studies:
a. Clinical Sensitivity: Not applicable
b. Clinical Specificity: Not applicable
c. Other Clinical Supportive Data (When 1. and 2. Are Not Applicable):
Reader Study
A reader study was conducted to assess the ability of potential users of Quantra System with the QStat Cartridge to correctly interpret results displayed on the Quantra Dials Display and Curve screens. The QStat Reader Study was conducted with a total of 10 readers who regularly assess the blood coagulation status of patients in the critical care setting. Participants viewed 12 QStat results display screens, each containing results for five QStat Cartridge parameters, and answered a total of 131 multiple-choice questions. For all five QStat parameters, >95% of the questions pertaining to each of the displays were answered correctly.
D. Clinical Cut-Off:
Not applicable.
E. Expected Values/Reference Range:
The reference range study was a multi-center study aimed at establishing reference range intervals for a healthy population for the test parameters measured by the QStat Cartridge on the Quantra Hemostasis Analyzer. The study population consisted of 155 healthy men and women volunteers (≥18 years of age) enrolled across four external sites that are representative of the general population in the United States.
K213917 - Page 24 of 25
{24}
| Output Parameter | Units | N | Reference Ranges |
| --- | --- | --- | --- |
| Clot Time (CT) | Seconds | 150 | 121 – 175 |
| Clot Stability to Lysis (CSL) | Percent | 151 | 92 – 100* |
| Clot Stiffness (CS) | hectoPascals | 151 | 14.0 – 35.4 |
| Platelet Contribution to Clot Stiffness (PCS) | hectoPascals | 153 | 12.8 – 32.3 |
| Fibrinogen Contribution to Clot Stiffness (FCS) | hectoPascals | 149 | 0.9 – 4.2 |
*The Clot Stability to Lysis (CSL) is a calculated parameter. CSL values of 92%–100% are demonstrated to be typical of "normal" patient samples. Samples with CSL values below 90% are indicative of reduction of clot stiffness that is likely due to the influence of fibrinolysis. The 90% threshold was calculated as the lower bound of the 95% confidence interval around the lower limit of the reference interval for CSL determined in healthy volunteers.
## VIII Proposed Labeling:
The labeling supports the finding of substantial equivalence for this device.
## IX Conclusion:
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.
K213917 - Page 25 of 25
