Table 6.
Adjunctive therapies for type 1 diabetes
| Variable | Metformin | Pramlintide | GLP-1 RA | SGLT-2 or SGLT-1/2 inhibitors |
|---|---|---|---|---|
| HbA1c reduction | ~1 mmol/mol (~0.1%) | 3–4 mmol/mol (0.3–0.4%) | 2–4 mmol/mol (0.2–0.4%) | 2–4 mmol/mol (0.2–0.4%) |
| Fasting glucose | Minimal effect | No effect | Minimal effect | Modest decrease (0.8 mmol/l [15 mg/dl]) |
| Postprandial glucose | Minimal effect | Significant decrease | Modest decrease | Modest decrease |
| TIR | No data | No data | No data | Increased (~12% at higher doses) |
| Insulin dose | Unchanged | Mealtime reductions | Predominantly mealtime reductions | Mealtime and basal reductions (~10% total reduction) |
| Body weight | Modest (~1 kg) | Modest (~1 kg) | Significant (~5 kg) | Moderate (2–3 kg) |
| Systolic blood pressure | No change | No change | 4 mmHg decrease (with increase in heart rate) | 3–4 mmHg decrease |
| Hypoglycaemia | Low risk | Potential increase in Level 3 hypoglycaemia if prandial insulin doses are not decreased | Increase in hypoglycaemia | Low risk |
| Side effects | GI side effects | GI side effects | GI side effects; increase in ketosis | Genital mycotic infections; increased risk of DKA |
| Approval status for type 1 diabetes in EU/US | Not currently approved | US approved | Not currently approved | EU approved low dose when BMI ≥27 kg/m2 |
| Specific groups for whom treatment may be of benefit | Women with polycystic ovary syndrome | No specific groups | Overweight and obese; high insulin dose; risk of cardiovascular and renal disease | Risk of cardiovascular and renal disease |
EU, European Union; GI, gastrointestinal