What is the preferred medication to add to metformin (biguanide) for a 17-year-old with type 2 diabetes, a body mass index (BMI) of 34, and a hemoglobin A1c (HbA1c) level of 7.8%?

From the Guidelines

For a 17-year-old with type 2 diabetes, BMI of 34, and HbA1c of 7.8% who is already on metformin, the preferred medication to add would be a GLP-1 receptor agonist, as supported by the most recent and highest quality study 1. The choice of a GLP-1 receptor agonist is based on its efficacy in improving glycemic control, promoting weight loss, and having a favorable safety profile in adolescents with type 2 diabetes.

• Key benefits of GLP-1 receptor agonists include:
  • Improvement in glycemic control
  • Promotion of weight loss, which is particularly beneficial for patients with elevated BMI
  • Low risk of hypoglycemia
  • Potential cardiovascular benefits
• The typical starting dose for a GLP-1 receptor agonist such as liraglutide is 0.6 mg subcutaneously once daily for one week, then increasing to 1.2 mg daily, with a maximum dose of 1.8 mg daily if needed for glycemic control, as indicated in studies 1.
• Common side effects of GLP-1 receptor agonists include nausea, vomiting, and diarrhea, which typically improve over time.
• Blood glucose monitoring should continue, and the patient should be counseled on proper injection technique and the importance of maintaining lifestyle modifications, including diet and exercise, alongside pharmacotherapy, as emphasized in 1.
• It's also worth noting that sodium–glucose cotransporter-2 inhibitors, such as empagliflozin, are now approved for use in youth with type 2 diabetes and have shown efficacy in reducing A1C levels, as seen in 1. However, the current recommendation prioritizes GLP-1 receptor agonists due to their additional benefits on weight loss and glycemic control.

From the FDA Drug Label

At the end of treatment, INVOKANA 300 mg provided greater HbA 1C reduction compared to sitagliptin 100 mg when added to metformin HCl and sulfonylurea (p<0. 05). INVOKANA 300 mg resulted in a mean percent change in body weight from baseline of -2.5% compared to +0.3% with sitagliptin 100 mg. A mean change in systolic blood pressure from baseline of -5.06 mmHg was observed with INVOKANA 300 mg compared to +0. 85 mmHg with sitagliptin 100 mg

The preferred medication to add to metformin for a 17-year-old with type 2 diabetes, a body mass index (BMI) of 34, and a hemoglobin A1c (HbA1c) level of 7.8% is canagliflozin (INVOKANA), as it has been shown to provide greater HbA1c reduction and weight loss compared to other medications such as sitagliptin when added to metformin. However, it is essential to consider the patient's age and potential side effects, and the decision should be made under the guidance of a healthcare professional. 2

From the Research

Preferred Medication to Add to Metformin

For a 17-year-old with type 2 diabetes, a body mass index (BMI) of 34, and a hemoglobin A1c (HbA1c) level of 7.8%, the preferred medication to add to metformin can be considered based on the following options:

• SGLT2 Inhibitors: Studies such as 3 and 4 suggest that SGLT2 inhibitors, like empagliflozin, can be effective in reducing HbA1c levels, fasting plasma glucose, and body weight in patients with type 2 diabetes inadequately controlled on metformin monotherapy.
• DPP-4 Inhibitors: Research like 5 and 6 indicates that DPP-4 inhibitors, such as sitagliptin, can also be used as add-on therapy to metformin, offering benefits like weight neutrality and low rates of hypoglycemia.

Key Considerations

When choosing a medication to add to metformin, consider the following:

• Efficacy: SGLT2 inhibitors and DPP-4 inhibitors have shown efficacy in improving glycemic control 3, 4, 6.
• Safety: Both classes of medications have been found to be generally safe, with SGLT2 inhibitors carrying a risk of urogenital infections and DPP-4 inhibitors being weight neutral 3, 4, 6.
• Additional Benefits: SGLT2 inhibitors may offer additional benefits like weight loss, blood pressure reduction, and cardiovascular risk reduction 4.

Patient-Specific Factors

The choice of medication should also take into account patient-specific factors, such as:

• Weight: For patients with a high BMI, like the 17-year-old in question, SGLT2 inhibitors may be preferred due to their weight-loss benefits 4.
• Comorbidities: The presence of comorbidities like heart failure or cardiovascular disease may also influence the choice of medication, with SGLT2 inhibitors being favored in such cases 4.