Side by side
MK-677 vs Thymalin
Both are discussed for anti-aging & longevity. What this site records about each, side by side. Every figure is on the compound's own page with the source it came from.
| MK-677 | Thymalin | |
|---|---|---|
| What it is | An orally active ghrelin receptor agonist that raises growth hormone and IGF-1. Not a peptide, and not injected. It is a small molecule taken by mouth. | A thymus extract used as a medicine in Russia for decades. Not a single defined peptide, which is the fact that governs everything else on this page. |
| EvidenceHow much human evidence exists, not how well it works. | Early human trials | Early human trials |
| Regulatory statusReviewed 2026-08-12 | Not approved for human use in any jurisdiction. Development was not completed. It is widely sold as a 'research chemical' or mislabelled as a dietary supplement, which it is not. It is an unapproved drug. | Registered as a medicine in Russia and several neighbouring states for immune-related indications. Not approved in the United States, the European Union or the United Kingdom, where it is sold only as a research chemical. Because it is an extract rather than a synthesised peptide, purity and composition vary between producers in a way they do not for defined peptides. |
| Routes | Oral | Intramuscular, Subcutaneous |
| Half-life | 24 hours | Not recorded |
| Cheapest per mgVials only, read from vendors' own listings and dated on the price index. | $0.64/mg | $1.30/mg |
| Median per mg | $2.94/mg | $4.50/mg |
| Vendors with a price | 6 | 13 |
| Storage once mixed | Not applicable. Liquid preparations sold in solution should follow the seller's storage instructions, which is a weaker guarantee than it sounds. | Refrigerated at 2–8 °C, and used within days rather than weeks. Biological extracts are less predictable in solution than synthetic peptides. |
Compare two other compounds · The full price index
This page is educational. It describes what published research reports, not what you should do. Peptides discussed here are largely not approved for human use, and nothing on BioAlmanac is medical advice. Nothing here ranks these two against each other. A table can show that one has more human evidence behind it or costs less per milligram; neither of those is a recommendation, and the right comparison for any person is one their doctor makes with them.