For a Medicare Part A and B beneficiary with eGFR ≥45 mL/min/1.73 m², which generic DPP‑4 inhibitor and which branded SGLT‑2 inhibitor are the most affordable oral glucose‑lowering options?

Most Affordable DPP-4 and SGLT2 Inhibitor Options for Medicare Part A & B

For a Medicare Part A and B beneficiary with eGFR ≥45 mL/min/1.73 m², alogliptin 25 mg is the cheapest DPP-4 inhibitor at $234 AWP/$154 NADAC per month, and ertugliflozin 15 mg is the cheapest SGLT2 inhibitor at $390 AWP/$312 NADAC per month. 1, 2

DPP-4 Inhibitor Cost Analysis

Alogliptin represents the most cost-effective DPP-4 inhibitor choice, with pricing data showing:

• Alogliptin 25 mg: $234 AWP/$154 NADAC monthly 1, 2
• Saxagliptin 5 mg: $565 AWP/$452 NADAC monthly 1
• Linagliptin 5 mg: $606 AWP/$485 NADAC monthly 1
• Sitagliptin 100 mg: $626 AWP/$500 NADAC monthly 1

The annual savings by choosing alogliptin over sitagliptin exceeds $2,900, making this a clinically significant cost difference for Medicare beneficiaries. 2, 3

Important Caveats for DPP-4 Selection

• All DPP-4 inhibitors have similar glycemic efficacy (HbA1c reduction ~0.5-1.0%) and low hypoglycemia risk 1, 4
• Alogliptin requires dose adjustment at eGFR <45: reduce to 12.5 mg daily at eGFR 30-44, and 6.25 mg daily at eGFR 15-29 1
• Linagliptin requires no dose adjustment at any eGFR level, which may offset cost considerations if renal function declines 1
• Sitagliptin requires reduction to 50 mg at eGFR 30-44 and 25 mg at eGFR 15-29 1

SGLT2 Inhibitor Cost Analysis

Ertugliflozin is the least expensive SGLT2 inhibitor, though this comes with important clinical limitations:

• Ertugliflozin 15 mg: $390 AWP/$312 NADAC monthly 1
• Dapagliflozin 10 mg: $659 AWP/$527 NADAC monthly 1
• Canagliflozin 300 mg: $684 AWP/$548 NADAC monthly 1
• Empagliflozin 25 mg: $685 AWP/$547 NADAC monthly 1

Critical Clinical Considerations for SGLT2 Selection

The cost advantage of ertugliflozin is offset by lack of cardiovascular and renal outcome trial data. 1

Empagliflozin and canagliflozin have proven cardiovascular mortality reduction in patients with established ASCVD, making them preferred choices despite higher cost when cardiovascular disease is present. 1

For patients prioritizing kidney protection with eGFR ≥25 mL/min/1.73 m², dapagliflozin has FDA approval and proven renal outcomes, justifying its higher cost. 1

SGLT2 Inhibitor Dosing at Lower eGFR

• Ertugliflozin: Not recommended for initiation at eGFR <45 1
• Empagliflozin: Not recommended for use at eGFR <45 per FDA label (though newer data supports use to eGFR 20) 1
• Dapagliflozin: Can be initiated down to eGFR 25, continued to dialysis 1
• Canagliflozin: Maximum 100 mg at eGFR 30-44, can continue to dialysis 1

Medicare Part A & B Specific Considerations

Medicare Part A & B alone does not cover outpatient prescription drugs—patients need Part D or a supplement for medication coverage. 2

If the patient has a Blue Cross supplement with drug coverage, verify formulary tier placement, as alogliptin and ertugliflozin may have different copay structures despite lower base prices. 2

Check for Low-Income Subsidy (LIS) eligibility, which can dramatically reduce out-of-pocket costs regardless of which agent is chosen. 2

Clinical Algorithm for Selection

Step 1: Verify Metformin Trial

• Confirm metformin has been tried first (costs only $2-4/month) unless contraindicated 2, 3

Step 2: Assess Cardiovascular and Renal Status

• If established ASCVD or heart failure: Choose empagliflozin or canagliflozin over ertugliflozin despite higher cost 1
• If CKD with eGFR 25-44: Choose dapagliflozin for proven kidney protection 1
• If neither condition present and eGFR ≥45: Ertugliflozin is acceptable for cost savings 1

Step 3: DPP-4 Inhibitor Selection

• If eGFR ≥45 and stable: Choose alogliptin 25 mg 1, 2
• If eGFR declining or <45: Consider linagliptin (no dose adjustment needed) to avoid future dose reductions 1

Step 4: Common Pitfalls to Avoid

• Do not combine DPP-4 inhibitors with GLP-1 receptor agonists—redundant mechanisms via GLP-1 signaling 5
• Counsel on genital mycotic infections with SGLT2 inhibitors (6% incidence vs 1% placebo), more common in women 1
• Warn about euglycemic ketoacidosis risk with SGLT2 inhibitors, especially during acute illness—consider pausing therapy during stressors 1
• Maintain at least low-dose insulin if patient is on insulin plus SGLT2 inhibitor to reduce ketoacidosis risk 1