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The FLOW trial (NEJM 2024) showed semaglutide reduced major kidney events 24% in adults with type 2 diabetes and chronic kidney disease. Stopped early for efficacy. This positions semaglutide alongside SGLT2 inhibitors as a renoprotective agent in T2D + CKD — and raises questions about effects in CKD without diabetes.
FLOW enrolled 3,533 adults with T2D and stage 2–4 CKD (eGFR 25–75 mL/min/1.73m² with elevated albuminuria). Randomized to semaglutide 1.0 mg weekly or placebo, on top of standard renoprotective therapy (ACE inhibitor or ARB).
| Endpoint | Semaglutide | Placebo | Effect |
|---|---|---|---|
| Composite kidney endpoint | (reduced) | (higher) | HR 0.76 (24% reduction) |
| Persistent ≥50% eGFR decline | (reduced) | (higher) | HR 0.74 |
| Kidney failure (KRT or sustained eGFR <15) | (reduced) | (higher) | HR 0.80 |
| Kidney or CV death | (reduced) | (higher) | HR 0.71 |
| All-cause mortality | (reduced) | (higher) | HR 0.80 |
Trial stopped early for efficacy. Trial duration median 3.4 years.
Beyond glycemic and weight effects, GLP-1 receptor agonists appear to have direct renoprotective effects. Proposed mechanisms include reduced glomerular hyperfiltration, reduced oxidative stress, anti-inflammatory effects on the renal interstitium, and blood pressure reduction. The benefit appears additive to ACE/ARB therapy and likely complementary to SGLT2 inhibitor benefit.
FLOW was T2D-only. The FLOW-NoDM trial program (in CKD without T2D) is enrolling. Mechanism would suggest benefit; trial evidence is forthcoming. SELECT showed mortality and CV benefit in obesity without diabetes; FLOW-NoDM extends that question to kidney endpoints.
For patients with T2D + CKD already on insurance-covered Ozempic, no change is suggested. For uninsured or out-of-pocket patients, compounded semaglutide has the same active ingredient effect; the renoprotective mechanism is from the molecule itself. However, dose is meaningful: FLOW used semaglutide 1.0 mg weekly. Some compounded programs default to titrations targeting weight loss endpoints (2.4 mg-equivalent) rather than renoprotection endpoints. Patients with CKD-directed treatment goals should discuss target dose with the prescriber.