Ipamorelin vs MK-677
Research Verdict
Neither compound has a universal evidence advantage. Both peptides serve distinct research goals with comparable evidence; choose by target mechanism.
Quick Answers
Which is better, Ipamorelin or MK-677?
Neither compound has a universal evidence advantage. Both peptides serve distinct research goals with comparable evidence; choose by target mechanism.
What is the key difference between Ipamorelin and MK-677?
MK-677 has a 24-hour half-life producing continuous non-pulsatile GH elevation with some appetite stimulation and insulin resistance; ipamorelin produces discrete GH pulses with no cortisol, prolactin, or appetite effects - convenience vs. selectivity.
Evidence Comparison
MK-677: oral, Merck Phase 3 program (abandoned for frailty), larger human datasets (Nass 2008). Ipamorelin: injectable, Phase 2 post-operative ileus, demonstrated selectivity. MK-677 has more human exposure data; ipamorelin has the cleaner hormonal profile.
Evidence Context Favoring Ipamorelin
GH research requiring maximal hormonal selectivity with pulsatile GH release and no metabolic confounders.
Evidence Context Favoring MK-677
Oral dosing convenience, chronic GH elevation studies, or research requiring larger published human databases.
Side-by-Side Snapshot
| Evidence grade | Ipamorelin: Level B MK-677: Level B |
|---|---|
| Research status | Ipamorelin: Phase 2 MK-677: Phase 3 |
| Primary category | Ipamorelin: Growth Hormone MK-677: Growth Hormone |
| Cited studies | Ipamorelin: 3 MK-677: 4 |