Safety, pharmacokinetics, and pharmacodynamics of single doses of ipamorelin in healthy volunteers — VialBase Research

Summary

Phase 1 pharmacokinetic and pharmacodynamic study of ipamorelin in healthy human volunteers. Confirmed the dose-dependent GH-releasing properties of ipamorelin in humans and validated the selectivity profile previously demonstrated in animal studies — GH release without significant effects on cortisol or prolactin.

Key Findings

• Dose-dependent GH release with IV and SC administration in healthy humans
• Rapid onset: peak GH within 30-40 minutes of subcutaneous injection
• Short duration of action: GH levels return to baseline within 3-4 hours
• Confirmed selectivity: no significant cortisol or prolactin elevation at therapeutic doses
• Well-tolerated with no serious adverse events
• Pharmacokinetic half-life supports once- or twice-daily dosing

Methodology

Phase 1, single ascending dose study in 14 healthy male volunteers. Ipamorelin administered at escalating doses via IV and SC routes. Serial blood sampling for GH, cortisol, prolactin, and ipamorelin concentrations. Standard PK/PD modeling analysis.

Limitations

• Small sample size (n=14)
• Single-dose study only — no chronic dosing data
• Male volunteers only
• No assessment of body composition changes
• IV and SC routes only — no oral bioavailability
• Short observation window

Relevance to Content

Provides human pharmacokinetic data to support clinical dosing discussions. The rapid-onset, short-duration profile explains why bedtime dosing is recommended (mimics the natural nocturnal GH pulse). Important for practical content about ipamorelin timing and dosing.

See Also

• Parent compound: Ipamorelin