Summary:
In 178 adults with T2D (HbA1c 7.0-10.5%) on stable metformin, once-weekly semaglutide (0.25-1.0 mg) for 52 weeks produced numerically greater fat loss (3.4 vs 2.6 kg) and lean mass loss (2.3 vs 1.5 kg), but differences were not statistically significant; similar visceral fat reduction; greater total weight loss (5.3 vs 4.2 kg) compared to once-daily canagliflozin 300 mg, with GI adverse events more common with semaglutide; both preserved favorable fat-to-lean ratio.
| PICO | Description |
|---|---|
| Population | 178 adults with T2D (HbA1c 7.0-10.5%) on metformin ≥1500 mg, eGFR ≥60. |
| Intervention | Once-weekly semaglutide escalated to 1.0 mg for 52 weeks. |
| Comparison | Once-daily canagliflozin 300 mg for 52 weeks (no placebo). |
| Outcome | Similar body composition changes. Fat loss 3.4 vs 2.6 kg (NS). Weight -5.3 vs -4.2 kg. |
Semaglutide vs canagliflozin: body composition
RCT (SUSTAIN 8 substudy) · type 2 diabetes · 52 weeks
Fat and lean mass changes did not differ significantly between semaglutide and canagliflozin, despite greater total weight loss with semaglutide. Both preserved a favorable fat-to-lean ratio.
Clinical Context
Body composition matters – weight loss should come from fat, not lean mass. GLP-1 RAs and SGLT2i work through different mechanisms.
Clinical Pearls
1. Similar Body Composition Despite Different Mechanisms: Composition may depend more on caloric deficit than pharmacological pathway.
2. Both Preserve Favorable Fat-to-Lean Ratio: Neither produced excessive lean mass loss.
3. Greater Total Weight Loss with Semaglutide: 5.3 vs 4.2 kg absolute difference.
4. DXA Provides Objective Assessment: Separates fat, lean, and visceral fat precisely.
Practical Application
Body composition effects shouldn’t drive drug choice. Consider CV/renal benefits, glycemic efficacy, tolerability. Encourage protein intake and resistance training.
Study Limitations
No placebo arm. Missing DXA data. DXA can’t distinguish muscle from water. 52-week duration.
Bottom Line
Semaglutide and canagliflozin produce similar body composition changes despite different mechanisms and semaglutide’s greater total weight loss.
Source: McCrimmon R, et al. “Body Composition Effects of Semaglutide vs Canagliflozin: SUSTAIN 8 Substudy.” Diabetologia. 2020. Read article