LCD L38664: Implantable Continuous Glucose Monitors (I-CGM)

Compliance with the provisions in this LCD may be monitored and addressed through post payment data analysis and subsequent medical review audits.

History/Background and/or General Information

Diabetes mellitus (DM) is a chronic metabolic disease involving an underproduction or resistance to insulin, resulting in elevated blood glucose levels. The two most common types of diabetes are type 1 (T1DM) and type 2 (T2DM). 1 T1DM comprises approximately 5-10% of diabetes cases and describes an etiology in which an autoimmune response damages the insulin-producing beta cells of the pancreas, resulting in insufficient insulin production. Conversely, T2DM is characterized by insulin resistance. 1,2 In T2DM, an individual’s insulin production fails to offset the deficit that is created by the resistance. 1 T2DM constitutes an estimated 90%-95% of diabetes cases. 2

Approximately 11.3% of Americans have diagnosed diabetes, and an additional 3.4% of Americans are estimated to have undiagnosed diabetes. The prevalence of diabetes is known to increase with age. In Medicare-aged populations in the United States (≥ 65 years of age), 22.4% of the population has diagnosed diabetes, with an additional 4.7% estimated to have undiagnosed diabetes. 3 Economic evaluations have estimated that diabetes annually accounts for $237 billion in direct US medical expenditure, and an additional $90 billion in lost productivity. 4

Acute complications of diabetes include hypoglycemia, hyperglycemia, diabetic coma, and nonketotic hyperosmolar coma. Chronic hyperglycemia, resulting from poorly controlled diabetes, may result in serious and life-threatening damage, including dysfunction and failure of the eyes, kidneys, nervous system and cardiovascular system. The complications of diabetes mellitus are far less common and less severe in people who have well-controlled blood sugar levels. 1

To prevent and/or delay the development of both short- and long-term complications of diabetes, the American Diabetes Association (ADA) recommends person-centered care aimed at timely treatment decisions following evidence-based guidelines. Person-centered care goals include minimizing the progression of hyperglycemia with more intensive approaches for individuals at higher risk which include those with higher glucose levels (e.g., fasting blood glucose 110-125 mg/dL, 2-hour post-challenge glucose 173-199 mg/dL, A1C ≥ 6.0%). 5

Diabetes treatment relies on diet, exercise, lifestyle modifications, and in many, medications in order to keep their blood sugar under a stable and controlled level. Close glucose monitoring either multiple times a day or continuously may be warranted in those diabetics that are having difficulty maintaining that level. 1,6

Continuous glucose monitoring (CGM) devices measure glucose via interstitial fluid instead of blood. CGM systems traditionally rely on a multi-part system that often involves: 1.) a sensor that is inserted into subcutaneous tissue; 2.) a receiver/mobile application consisting of a display and interface; 3.) a transmitter component that is attached to the sensor and worn externally. 6,7 The sensors for these subcutaneous CGM systems need to be removed and replaced every 4 to 6 days depending upon the system. 6

Despite the number of benefits that subcutaneous CGM offer in the DM management paradigm, some CGM studies have reported relatively high attrition rates that patients attributed to discomfort, contact dermatitis, issues changing the sensors, and physical interference with activities of daily living. 8 The rationale for implantable continuous glucose monitoring (I-CGM) seeks to circumvent these negative patient experiences. Unlike with subcutaneous CGM, I-CGM involves a sensor that is surgically implanted for longer spans of time between replacement, allowing for skin barrier closure, and less frequent manipulation.

Covered Indications

Therapeutic I-CGMs are considered medically reasonable and necessary by Medicare when all of the following coverage criteria (1-4) are met:

• The beneficiary has diabetes mellitus; and ,

• The beneficiary’s treating practitioner has concluded that the beneficiary (or beneficiary’s caregiver) has sufficient training using the I-CGM prescribed as evidenced by providing a prescription; and ,

• The I-CGM is prescribed in accordance with its FDA indications for use; and ,

• The beneficiary for whom an I- CGM is being prescribed, to improve glycemic control, meets at least one of the criteria below:

• The beneficiary is insulin-treated; or,

• The beneficiary has a history of problematic hypoglycemia with documentation of at least one of the following:

• Recurrent (more than one) level 2 hypoglycemic events (glucose

ICGM Continued Coverage

Every 6 months following the initial prescription of the I-CGM, the treating practitioner conducts an in-person or Medicare-approved telehealth visit with the beneficiary to document adherence to their I-CGM regimen and diabetes treatment plan.

Limitations

I-CGM devices will be considered not medically reasonable and necessary for short-term (72 hours to 1 week) use.

Exception: Beneficiaries who have previously met the coverage criteria for a non-implantable therapeutic/non-adjunctive and non-therapeutic/adjunctive continuous glucose monitor through the Medicare DME benefit may subsequently choose to switch to the implantable device with a provider order. However, all other coverage criteria above must be fulfilled in order for Medicare payment.

Notice: Services performed for any given diagnosis must meet all of the indications and limitations stated in this LCD, the general requirements for medical necessity as stated in CMS payment policy manuals, any and all existing CMS national coverage determinations, and all Medicare payment rules.

Introduction

The primary aim of this summary of evidence is to determine if I-CGM performs with equivalent clinical validity, efficacy, safety, and patient perceived benefit when compared with subcutaneous CGM devices. The secondary aim of this summary of evidence is to evaluate the expected magnitude of benefit across the aforementioned outcomes resulting from the inclusion of I-CGM into the diabetes management paradigm.

At the time of this review, the Eversense E3 is the only device that has received clearance for use by the United States Food and Drug Administration (FDA). However, it is this Medicare Administrative Contractor’s expectation that additional devices are in the development and/or FDA approval process and soon may be publicly available. Hence, this policy is written to reflect coverage criteria and accompanying evidentiary review and analysis on I-CGM devices in an agnostic manner without the endorsement of any specific product.

Food and Drug Administration (FDA) Approvals