(396 days)
The FreeStyle Libre 2 Flash Glucose Monitoring System is a continuous glucose monitoring (CGM) device with real time alarms capability indicated for the management of diabetes in persons age 4 and older. It is intended to replace blood glucose testing for diabetes treatment decisions, unless otherwise indicated.
The System also detects trends and tracks patterns and aids in the detection of episodes of hyperglycemia and hypoglycemia, facilitating both acute and long-term therapy adjustments. Interpretation of the System readings should be based on the glucose trends and several sequential readings over time.
The System is also intended to autonomously communicate with digitally connected devices. The System can be used alone or in conjunction with these digitally connected devices where the user manually controls actions for therapy decisions.
The FreeStyle Libre 2 Flash Glucose Monitoring System with the FreeStyle Libre 2 App (herein referred to as the 'FreeStyle Libre 2 System' or 'System') is an integrated continuous glucose monitoring system (iCGM) that provides continuous glucose measurements every minute to provide glucose levels, trends and alerts. The System requires a prescription and is intended for home use. The System consists of the following components: a sensor which transmits via Bluetooth Low Energy (BLE), a BLE enabled display device (Reader), and an iOS mobile app (FreeStyle Libre 2 App) downloaded to a compatible smartphone. Scanning of the sensor via Reader or App provides the user with real-time glucose measurements (glucose values) accompanied by trend information (glucose arrows) and historical glucose information (glucose graph). The user may make treatment decisions based in part on the sensor glucose results provided by the System. The System also provides configurable alarms designed to warn the user of Low Glucose, High Glucose or Signal Loss.
The provided text describes the FreeStyle Libre 2 Flash Glucose Monitoring System (with FreeStyle Libre 2 App) and its substantial equivalence to a predicate device. However, the document primarily focuses on explaining the device, its intended use, comparison with a predicate, and the general types of performance testing conducted to support substantial equivalence for the app component.
Crucially, the acceptance criteria and detailed study results proving the device meets those criteria (specific performance metrics, sample sizes for clinical trials, ground truth establishment, expert adjudication, MRMC studies, etc.) are NOT explicitly present in this excerpt. The document states "no additional clinical data beyond that provided in K193371 was used in this 510(k) to support a determination of substantial equivalence" for clinical performance, indicating reliance on prior submissions for the predicate device. Therefore, a comprehensive answer for the requested points regarding the study that proves the device meets the acceptance criteria cannot be fully extracted from this document alone.
However, based on the information provided, I can infer and answer parts of your request.
Here's an attempt to answer your questions based on the provided text, and where information is missing, I will clearly state that:
Device: FreeStyle Libre 2 Flash Glucose Monitoring System (with FreeStyle Libre 2 App)
Predicate Device: FreeStyle Libre 2 Flash Glucose Monitoring System (K193371)
A Table of Acceptance Criteria and Reported Device Performance:
The document does not provide a specific table of acceptance criteria with corresponding performance metrics. It generally states that "Results of executed protocols met the acceptance criteria" for various tests, but does not quantify these criteria or the results.
| Acceptance Criteria (Inferred from general statements) | Reported Device Performance (General Statement in document) |
|---|---|
| Software Verification and Validation: Meets established specifications and IEC 62304 guidance. | "Results of executed protocols for the met the acceptance criteria and therefore supports that the System's embedded software is acceptable for its intended use." |
| Human Factors: Meets usability requirements. | "Results demonstrated that the System met usability requirements." |
| Wireless Coexistence: Tolerates interference from various RF interfering devices and meets target performance criteria. | "Test results showed the System could tolerate interference generated by these RF interfering devices and still meet the target performance criteria." |
| Cybersecurity: Risk mitigation controls are implemented and tested. | "Appropriate risk mitigation controls have been implemented and tested." |
| Electrical Safety and EMC: Complies with IEC 60601-1:2005(r)2012 and IEC 60601-1-2:2014. | "demonstrated that the System complies with electrical safety and EMC requirements." |
| Clinical Performance (Accuracy) | "The App utilizes the identical algorithm and implements the same wireless interfaces with the Sensor as used by the Reader. As the App calculates glucose information identically to the Reader, no additional clinical data beyond that provided in K193371 was used in this 510(k) to support a determination of substantial equivalence." (This implies that the clinical performance established for the predicate device is considered applicable and meets criteria, but specific numbers are not here). |
1. Sample sized used for the test set and the data provenance:
- Sample Size for Test Set: Not specified in this document. The document states that no additional clinical data was used for this 510(k) beyond what was presented in K193371 (the predicate device's submission). The performance testing described (Software V&V, Human Factors, Wireless Coexistence, Cybersecurity, Electrical Safety/EMC) are generally system-level or component-level tests, not direct patient clinical trials with specific "test sets" in the sense of clinical data.
- Data Provenance: Not specified for the clinical data that supports the predicate device (K193371). For the testing described in this document (Software, Human Factors, etc.), it's implied to be internal testing by Abbott Diabetes Care Inc. and conducted in laboratory environments. The document does not specify if it's retrospective or prospective.
2. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The document does not describe specific "ground truth" establishment for a clinical test set in this submission, as it defers to a previous 510(k) (K193371) for clinical performance data. Therefore, the number and qualifications of experts for establishing clinical ground truth are not provided here.
- For Human Factors testing, "usability requirements" were met, implying expert evaluation or user testing, but the specifics of who established the "ground truth" or expert qualifications are not detailed.
3. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable/Not specified. Since clinical data specifics are not provided in this submission (deferring to K193371), there's no mention of an adjudication method commonly used in clinical trials for ground truth.
4. 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:
- Not applicable. This device is a Continuous Glucose Monitoring (CGM) system, not an AI-assisted diagnostic imaging device that involves human "readers" interpreting cases. Therefore, an MRMC study is not relevant to this device type.
5. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- The document implies that standalone performance of the algorithm was assessed for the core glucose measurement. It states, "The App utilizes the identical algorithm and implements the same wireless interfaces with the Sensor as used by the Reader. As the App calculates glucose information identically to the Reader..." This suggests that the algorithm's performance in converting raw sensor measurements to glucose values was established and relied upon from the predicate device's data (K193371). No specific standalone performance metrics are provided in this document, but the fact that the algorithm is "identical" means its standalone performance is assumed to be the same as the predicate.
6. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- For the clinical performance of a CGM, the ground truth typically involves lab-based reference glucose measurements (e.g., YSI analyzer or similar highly accurate methods) from blood samples taken concurrently with sensor readings. However, none of these specifics for ground truth are provided in this document, as it refers back to K193371 for clinical data.
7. The sample size for the training set:
- Not specified. The document does not discuss the training of the glucose algorithm. It merely confirms that the app uses the "identical algorithm" as the predicate device.
8. How the ground truth for the training set was established:
- Not specified. As the document does not detail the training set, it also does not elaborate on how its ground truth was established.
In summary, this 510(k) summary focuses on demonstrating substantial equivalence for the addition of an app to an already cleared CGM system. It relies heavily on the clinical performance and established ground truth from the predicate device's prior submission (K193371) for the core glucose measurement accuracy. The testing described in this particular document pertains mostly to software validation, human factors, wireless communication, cybersecurity, and electrical safety/EMC, which are specific to the new app component and its interaction with the existing system, rather than new clinical accuracy studies.
§ 862.1355 Integrated continuous glucose monitoring system.
(a)
Identification. An integrated continuous glucose monitoring system (iCGM) is intended to automatically measure glucose in bodily fluids continuously or frequently for a specified period of time. iCGM systems are designed to reliably and securely transmit glucose measurement data to digitally connected devices, including automated insulin dosing systems, and are intended to be used alone or in conjunction with these digitally connected medical devices for the purpose of managing a disease or condition related to glycemic control.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Design verification and validation must include the following:
(i) Robust clinical data demonstrating the accuracy of the device in the intended use population.
(ii) The clinical data must include a comparison between iCGM values and blood glucose values in specimens collected in parallel that are measured on an FDA-accepted laboratory-based glucose measurement method that is precise and accurate, and that is traceable to a higher order (
e.g., an internationally recognized reference material and/or method).(iii) The clinical data must be obtained from a clinical study designed to fully represent the performance of the device throughout the intended use population and throughout the measuring range of the device.
(iv) Clinical study results must demonstrate consistent analytical and clinical performance throughout the sensor wear period.
(v) Clinical study results in the adult population must meet the following performance requirements:
(A) For all iCGM measurements less than 70 milligrams/deciliter (mg/dL), the percentage of iCGM measurements within ±15 mg/dL of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 85 percent.
(B) For all iCGM measurements from 70 mg/dL to 180 mg/dL, the percentage of iCGM measurements within ±15 percent of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 70 percent.
(C) For all iCGM measurements greater than 180 mg/dL, the percentage of iCGM measurements within ±15 percent of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 80 percent.
(D) For all iCGM measurements less than 70 mg/dL, the percentage of iCGM measurements within ±40 mg/dL of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 98 percent.
(E) For all iCGM measurements from 70 mg/dL to 180 mg/dL, the percentage of iCGM measurements within ±40 percent of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 99 percent.
(F) For all iCGM measurements greater than180 mg/dL, the percentage of iCGM measurements within ±40 percent of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 99 percent.
(G) Throughout the device measuring range, the percentage of iCGM measurements within ±20 percent of the corresponding blood glucose value must be calculated, and the lower one-sided 95 percent confidence bound must exceed 87 percent.
(H) When iCGM values are less than 70 mg/dL, no corresponding blood glucose value shall read above 180 mg/dL.
(I) When iCGM values are greater than 180 mg/dL, no corresponding blood glucose value shall read less than 70 mg/dL.
(J) There shall be no more than 1 percent of iCGM measurements that indicate a positive glucose rate of change greater than 1 mg/dL per minute (/min) when the corresponding true negative glucose rate of change is less than −2 mg/dL/min as determined by the corresponding blood glucose measurements.
(K) There shall be no more than 1 percent of iCGM measurements that indicate a negative glucose rate of change less than −1 mg/dL/min when the corresponding true positive glucose rate of change is greater than 2 mg/dL/min as determined by the corresponding blood glucose measurements.
(vi) Data demonstrating similar accuracy and rate of change performance of the iCGM in the pediatric population as compared to that in the adult population, or alternatively a clinical and/or technical justification for why pediatric data are not needed, must be provided and determined by FDA to be acceptable and appropriate.
(vii) Data must demonstrate that throughout the claimed sensor life, the device does not allow clinically significant gaps in sensor data availability that would prevent any digitally connected devices from achieving their intended use.
(2) Design verification and validation must include a detailed strategy to ensure secure and reliable means of iCGM data transmission to provide real-time glucose readings at clinically meaningful time intervals to devices intended to receive the iCGM glucose data.
(3) Design verification and validation must include adequate controls established during manufacturing and at product release to ensure the released product meets the performance specifications as defined in paragraphs (b)(1) and (b)(2) of this section.
(4) The device must demonstrate clinically acceptable performance in the presence of clinically relevant levels of potential interfering substances that are reasonably present in the intended use population, including but not limited to endogenous substances and metabolites, foods, dietary supplements, and medications.
(5) The device must include appropriate measures to ensure that disposable sensors cannot be used beyond its claimed sensor wear period.
(6) Design verification and validation must include results obtained through a usability study that demonstrates that the intended user can use the device safely and obtain the expected glucose measurement accuracy.
(7) The labeling required under § 809.10(b) of this chapter must include a separate description of the following sensor performance data observed in the clinical study performed in conformance with paragraph (b)(1) of this section for each intended use population, in addition to separate sensor performance data for each different iCGM insertion or use sites (
e.g., abdomen, arm, buttock):(i) A description of the accuracy in the following blood glucose concentration ranges: less than 54 mg/dL, 54 mg/dL to less than 70 mg/dL, 70 to 180 mg/dL, greater than 180 to 250 mg/dL, and greater than 250 mg/dL.
(ii) A description of the accuracy of positive and negative rate of change data.
(iii) A description of the frequency and duration of gaps in sensor data.
(iv) A description of the true, false, missed, and correct alert rates and a description of the available glucose concentration alert settings, if applicable.
(v) A description of the observed duration of iCGM life for the device.