Alirocumab (Praluent®)
| Drug Overview |  |
|---|---|
| Drug Class | PCSK9 Inhibitors |
| Mechanism | PCSK9 Monoclonal Antibody |
| Primary Uses | ASCVD; Familial Hypercholesterolemia |
| Route | Subcutaneous Injection |
| Dosing Interval | Every 2–4 weeks |
| LDL Reduction | ~50–60% |
| Metabolism | Reticuloendothelial degradation |
| Elimination | Proteolytic catabolism |
| Renal Adjustment | No |
| Hepatic Adjustment | No |
| Black Box Warning | No |
| FDA Approval | 2015 |
Overview
Alirocumab is a fully human monoclonal antibody that inhibits circulating PCSK9.
It is used in high-risk patients who require additional LDL reduction beyond maximally tolerated statins and ezetimibe.
It significantly reduces LDL cholesterol and improves cardiovascular outcomes.
Mechanism of Action
Normal Physiology:
- PCSK9 binds LDL receptors
- Promotes receptor degradation
- ↓ LDL receptor recycling
- ↑ Circulating LDL
Alirocumab Effect:
- Binds circulating PCSK9
- Prevents LDL receptor degradation
- ↑ LDL receptor recycling
- ↑ LDL clearance
Net Result:
- 50–60% additional LDL reduction
- Reduced ASCVD events
See:
Indications
Used primarily in secondary prevention.
Dosing
Typical Dosing:
- 75 mg subcutaneously every 2 weeks
- May increase to 150 mg every 2 weeks if needed
Alternative:
- 300 mg every 4 weeks (selected patients)
No renal or hepatic adjustment required.
Clinical Outcomes
Demonstrated:
- Significant LDL reduction (~50–60%)
- Reduced major adverse cardiovascular events (MACE)
Typically lowers LDL to <55 mg/dL in very high-risk patients.
Adverse Effects
Common:
- Injection site reactions
- Mild upper respiratory symptoms
Rare:
- Hypersensitivity reactions
No significant myopathy signal.
No clinically significant hepatic toxicity.
Drug Interactions
No CYP-mediated interactions.
Safe to combine with:
Minimal pharmacokinetic interaction risk.
Monitoring
- Lipid panel 4–12 weeks after initiation
- Assess LDL response
- Monitor for injection site reactions
Comparison Within Class
Compared to Evolocumab:
- Similar LDL reduction
- Similar outcome data
- Similar dosing frequency
Compared to Inclisiran:
- More frequent dosing (every 2–4 weeks)
- Monoclonal antibody vs siRNA mechanism
- Faster onset
Clinical Role:
- Add-on therapy after statin ± ezetimibe
- Very high-risk ASCVD patients
High-Yield Pearls
- ~50–60% LDL reduction
- Injectable therapy
- Minimal drug interactions
- Additive to statin therapy
- Insurance authorization often required