What's coming

Category 1 - Beyond GLP-1

Ozempic and Mounjaro changed the conversation, but they're version 1.0 of the metabolic peptide.

Retatrutide is a triple agonist (GLP-1 + GIP + glucagon) currently in late-stage trials. Phase 2 data showed roughly 24% body weight loss at 48 weeks - meaningfully more than tirzepatide. Phase 3 will tell us about long-term safety, and an FDA decision is expected in 2026 or 2027.

Cagrilintide combinations add an amylin-mimetic to GLP-1s. Targets the satiety pathway through a different receptor. Novo Nordisk's CagriSema (cagrilintide + semaglutide) is in Phase 3.

Oral GLP-1s. Pills, not shots. Several are in late development. The compliance story is obvious - patients who hate needles will take a pill. Whether the bioavailability holds up is the open question.

The thesis: the GLP-1 class is going to keep splitting. More targets per molecule. More indications (PCOS, NASH liver disease, cardiovascular protection beyond glucose, cognitive decline). The next decade looks like the statin decade of the 2000s - the class becomes table stakes for cardiometabolic health.

Category 2 - Longevity peptides

This is the spicier category. The data is thinner. The opportunity is larger.

Klotho is a protein your kidneys produce that declines with age. People with naturally high klotho live longer. Animal studies showed klotho supplementation reverses certain aging-related cognitive deficits. Several biotechs are developing klotho-based therapeutics. Watch the trial readouts.

MOTS-c is a mitochondrial-derived peptide - a 16-amino-acid signal your mitochondria release that affects metabolism, insulin sensitivity, and exercise capacity. Animal evidence is striking; human trials are early. If even half the animal effects translate, MOTS-c becomes interesting.

Epitalon is the legacy Russian longevity peptide. Mostly Russian-language research, telomere claims that are hard to verify, decades-long anecdotal use in Eastern Europe. Western pharma hasn't run rigorous trials. Watch this space - if a major Western lab decides to run a proper RCT on Epitalon, the field will move quickly.

Cerebrolysin is a porcine-brain-derived peptide cocktail used in Europe and Asia for stroke recovery and cognitive decline. Some clinical evidence. FDA-unapproved in the US but available via compounding in some states.

The thesis: if any of klotho, MOTS-c, or a serious Epitalon successor gets credible Phase 3 data, the longevity-peptide category opens up the same way GLP-1 did. The cultural appetite is there. The science needs to catch up.

Category 3 - The neuropeptides

Peptides that act on the brain, not the body.

Selank and Semax are Russian-developed nasal-spray neuropeptides. Anti-anxiety and cognitive-enhancement claims, mostly from Russian-language literature. Used clinically in Russia for decades. Western trials are minimal but the safety record is reasonable.

DSIP (Delta Sleep-Inducing Peptide) is the niche option for sleep architecture - particularly delta-wave sleep. Limited clinical evidence; mostly used by serious biohackers and a small set of sleep researchers.

PT-141 (bremelanotide) is FDA-approved for hypoactive sexual desire disorder under the brand Vyleesi. The first peptide-based libido drug. Acts on melanocortin receptors in the brain. Off-label use is widespread.

The thesis: neuropeptides are the most under-explored category in mainstream Western medicine. The Russian and Ukrainian research base has a 30-year head start that Western medicine is slowly catching up on.

What to actually do about any of this

If you're reading this and wondering whether to act:

1. Subscribe to the dispatch. When new trial data drops, when a peptide gets reclassified, when a vendor goes bad - we cover it weekly. Free.
2. Don't buy on hype. Most peptides on most vendor websites have weaker evidence than the marketing implies. Use the Tier List to filter signal from noise.
3. Talk to your doctor before you buy anything injectable. Not because they'll always say yes - many will say wait - but because their no is itself useful information.
4. Start with the proven category. If you have a metabolic concern (overweight, insulin resistance, PCOS, NASH), the GLP-1 class is the most-validated peptide intervention available right now. Telehealth makes it accessible.
5. Be patient on the longevity stuff. The thesis is real, the timeline is uncertain. Subscribe and wait for trial readouts before committing money.

Where to go next

• What are peptides - foundation
• How they work - mechanism
• The history - 100-year arc
• The Directory - 17 specific peptides reviewed
• The Tier List - which ones to take seriously
• The Protocols - how to actually use them

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