Tirzepatide QwikPen Formulation
Tirzepatide is formulated as a once-weekly subcutaneous injection with a half-life of 116.7 hours, available in doses of 2.5 mg, 5 mg, 7.5 mg, 10 mg, 12.5 mg, and 15 mg per injection. 1
Key Formulation Details
Molecular Structure:
- Tirzepatide is a synthetic peptide consisting of 39 amino acids 2
- It is a single molecule engineered from the native glucose-dependent insulinotropic polypeptide (GIP) sequence 1
- Contains a C20 fatty-diacid portion attached via acylation technology that binds to albumin, enabling once-weekly dosing 3
Pharmacokinetic Properties:
- Half-life: 116.7 hours (approximately 5 days) 1, 3
- Route: Subcutaneous injection only 1, 4
- Frequency: Once weekly 1, 4
- Metabolism: Metabolites are excreted through urine and feces 2
Dosing Algorithm
Starting dose: 2.5 mg weekly 1
Titration schedule: Increase monthly by 2.5 mg increments 1
Available doses: 2.5 mg → 5 mg → 7.5 mg → 10 mg → 12.5 mg → 15 mg weekly
FDA-approved therapeutic doses: 5 mg, 10 mg, and 15 mg weekly 1
Maximum dose: 15 mg weekly 1
Clinical Context
The formulation was specifically designed to achieve:
- Dual GIP/GLP-1 receptor agonism from a single molecule 1
- Extended duration of action through albumin binding 3
- Convenient once-weekly administration 1, 4
- Dose flexibility for individualized titration based on tolerability 1
Important caveat: The slow monthly titration from the 2.5 mg starting dose is essential to minimize gastrointestinal side effects, which occur most commonly during dose escalation 1. Patients who discontinue treatment must restart at the lowest dose and re-titrate to allow the body to re-acclimate 1.