Background
LEADER was one of the first GLP-1 receptor agonist cardiovascular outcome trials (CVOTs) required by the FDA. It evaluated liraglutide in patients with type 2 diabetes who had established cardiovascular disease or were at high cardiovascular risk.
The results of LEADER, alongside EMPA-REG OUTCOME, fundamentally changed the treatment algorithm for type 2 diabetes with cardiovascular comorbidity.
Methods
Phase 3b, randomized, double-blind, placebo-controlled, event-driven superiority trial across 410 sites in 32 countries. Participants had type 2 diabetes (HbA1c ≥7%), were ≥50 years with established CVD, or ≥60 years with cardiovascular risk factors.
Primary endpoint: MACE (cardiovascular death, nonfatal MI, nonfatal stroke).
Key Findings
| Outcome | Liraglutide | Placebo | HR (95% CI) |
|---|---|---|---|
| Primary MACE | 13.0% | 14.9% | 0.87 (0.78–0.97) |
| Cardiovascular death | 4.7% | 6.0% | 0.78 (0.66–0.93) |
| All-cause mortality | 8.2% | 9.6% | 0.85 (0.74–0.97) |
| Nonfatal MI | 6.0% | 6.8% | 0.88 (0.75–1.03) |
| HbA1c (end) | −0.40% net | — | — |
| Body weight | −2.3 kg net | — | — |
Clinical Significance
LEADER established liraglutide as the first GLP-1 agonist proven to reduce cardiovascular mortality in type 2 diabetes — a landmark finding that reshaped diabetes guidelines worldwide. The cardiovascular death reduction (22% RRR) was particularly impactful.
This led to an FDA label update in 2017 for cardiovascular risk reduction and made liraglutide a first-line agent for T2DM patients with CVD in major guidelines (ADA, ESC).
Limitations
- Only patients at high cardiovascular risk enrolled — not generalizable to lower-risk T2DM
- Mechanism of benefit unclear (weight, blood pressure, anti-inflammatory, or direct vascular effects)
- Open-label anti-hyperglycemic rescue medications permitted