(28 days)
The Dexcom G7 Continuous Glucose Monitoring (CGM) System is a real time, continuous glucose monitoring device indicated for the management of diabetes in persons 2 years and older.
The Dexcom G7 CGM System is intended to replace fingerstick BG testing for diabetes treatment decisions. Interpretation of the Dexcom G7 CGM System results should be based on the glucose trends and several sequential sensor readings over time. The Dexcom G7 CGM System also aids in the detection of episodes of hyperglycemia and hypoglycemia, facilitating both acute and long-term therapy adjustments.
The Dexcom G7 CGM System is also intended to autonomously communicate with digitally connected devices, including automated insulin dosing (AID) systems. The Dexcom G7 CGM System can be used alone or in conjunction with these digitally connected medical devices for the purposes of managing diabetes.
The Dexcom G7 Continuous Glucose Monitoring System) is an interoperable connected device that measures and displays estimated dlucose values for people with diabetes. The G7 System consists of the following components: the Glucose Sensing Subsystem (GSS), the Mobile Application Subsystem (MAS), the Receiver Subsystem (RVS), The GSS is comprised of the sensor applicator and on-body wearable, which includes a Bluetooth Low Energy (BLE) transmitter, adhesive patch and sensor. The sensor is a small and flexible wire, which is inserted by the applicator into subcutaneous tissue where it converts glucose into electrical current. The sensor has an expected wear period of up to 10 days with an extended 12-hour grace period after the sensor session. The grace period allows additional time for the user to change the sensor at a convenient time.
The transmitter is pre-connected to the sensor and is cradled into the applicator needle inside the applicator housing. The applicator external housing consists of a cap and shroud which utilize a threaded cap and seal to create the sterile barrier system. A deployment lock mechanism prevents insertion of the on-body wearable until the applicator is pressed against the insertion site. The insertion is then completed with a single button press vertical spring deployed mechanism, which introduces the sensor via the subcutaneous tissue while also placing the embedded wearable onto the body. The wearable adheres to the skin via an adhesive patch.
After deployment, the transmitter initiates automatic wakeup and session start. The sensor's small and flexible wire converts qlucose to electrical current and the transmitter samples the electrical current produced by the sensor. The transmitter's onboard algorithm converts these measurements into estimated qlucose values and calculates the glucose rate of change; the data are sent every 5 minutes to the MAS and/or the RVS. The MAS and RVS are display devices that present the current ducose reading and glucose trend to the user. Both display devices alert the user when glucose levels are outside of a target zone and when specific system states occur. The G7 System is designed to communicate to one or both display devices simultaneously.
The G7 System is also designed to communicate estimated glucose values, trend and system information to other compatible electronic interfaces via the following secure wireless connections:
- . Wireless communication from the transmitter directly to an interoperable device communicating through the same protocol
- . The app communicates to another app on a single mobile platform
- The app communicates through the cloud to another software device ●
- Dexcom Partner Web APIs: The Dexcom Partner Web APIs enable secure and o reliable communication of CGM data to authorized client software intended to receive the data through the cloud. The Partner Web APIs is not intended to be used by automated insulin delivery systems (AID).
The proposed G7 CGM System uses the same mode of operation and mechanism of reaction as the predicate G7 CGM System (K213919). The proposed G7 CGM System uses an alternate GSS wearable adhesive.
The provided text describes a 510(k) premarket notification for the Dexcom G7 Continuous Glucose Monitoring (CGM) System. The submission is for a modification to an already cleared device, specifically changing the adhesive patch.
Since this is a submission for a modification, the document frequently refers to the "predicate device" (K213919), which is essentially the previous version of the Dexcom G7. The current submission argues that the modified device is "substantially equivalent" to this predicate. As such, the performance data presented (or referenced indirectly) in this document likely refers to the performance of the predicate device, which the modified device is claimed to match.
Here's an analysis of the acceptance criteria and study information, extracting what's available and noting what is not explicitly stated in this particular document:
1. A table of acceptance criteria and the reported device performance
The document states: "The proposed Dexcom G7 CGM System was verified and validated according to Dexcom's internal design control process and in accordance with special controls for integrated continuous glucose monitoring systems. This testing demonstrated that the proposed system performed according to its specifications; and the proposed system has met its technological and performance criteria which have not changed from the predicate device."
This statement asserts that the device meets its performance criteria and specifications, and that these criteria have not changed from the predicate device. However, the exact quantitative acceptance criteria (e.g., specific MARD values, accuracy at different glucose ranges) and the reported device performance against those criteria are not explicitly provided in this document. This information would typically be found in the full 510(k) submission not included here, likely in the sections detailing the clinical study for the original device clearance (K213919).
2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective)
This document explicitly states it is a modification to a previously cleared device. It only mentions that the "proposed Dexcom G7 CGM System was verified and validated according to Dexcom's internal design control process and in accordance with special controls for integrated continuous glucose monitoring systems."
Therefore, the specific sample size, data provenance (country of origin), and whether the study was retrospective or prospective are not provided in this document. This information would be crucial for the original submission (K213919) that established the performance of the Dexcom G7.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
Given that this is a Continuous Glucose Monitoring (CGM) system, the "ground truth" for glucose measurements is typically established using a reference laboratory blood glucose analyzer, not human experts. Therefore, the concept of "number of experts" is not applicable in the context of establishing ground truth for glucose values in this type of device.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Since the ground truth is established by a laboratory analyzer, there is no adjudication method involving human experts for the glucose values themselves.
5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
The Dexcom G7 is a standalone medical device that measures glucose; it is not an AI-assisted diagnostic imaging device that involves human readers interpreting images. Therefore, a multi-reader multi-case (MRMC) comparative effectiveness study with human readers assisting AI is not applicable to this device.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This document describes the Dexcom G7 CGM System as "a real time, continuous glucose monitoring device." Its core function is to measure and display estimated glucose values. The device includes a "transmitter's onboard algorithm" that "converts these measurements into estimated glucose values and calculates the glucose rate of change." It also states, "The Dexcom G7 CGM System is intended to replace fingerstick BG testing for diabetes treatment decisions." This strongly implies that the device is intended for standalone performance in providing glucose measurements that can be used directly for treatment decisions, without requiring human interpretation of raw sensor data or assistance from human operators to derive the glucose values themselves.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The ground truth for a CGM device is established by comparison with a highly accurate reference method for measuring blood glucose, typically a laboratory-grade blood glucose analyzer (e.g., YSI analyzer) measuring venous blood samples. This is mentioned implicitly by the nature of CGM device testing.
8. The sample size for the training set
This document pertains to a 510(k) submission for a modified device, specifically a change in adhesive. While the device (and its underlying algorithm) would have been developed using training data, the size of that training set is not provided in this specific document. It would have been part of the original K213919 submission.
9. How the ground truth for the training set was established
Similar to the ground truth for the test set, the ground truth for any training data used for the algorithm in a CGM device would have been established by comparison with a highly accurate reference method for measuring blood glucose, usually a laboratory blood glucose analyzer. This information is not explicitly provided in this document but is standard practice for CGM development.
In summary:
This 510(k) submission for the Dexcom G7 focuses on demonstrating substantial equivalence of a modified device (specifically, a new adhesive) to a previously cleared predicate device. It asserts that the modifications do not change the intended use or fundamental scientific technology, and that the device continues to meet its performance specifications. However, the detailed performance data, study design, and sample sizes for the original clinical validation (which would contain the answers to many of these questions) are not included in this summary document. This document emphasizes that "the proposed G7 CGM System uses the same mode of operation and mechanism of reaction as the predicate G7 CGM System (K213919)" and its "technological and performance criteria ... have not changed from the predicate device."
§ 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.