Peptide Evidence-Grade Index

Of 18 commonly discussed peptides, only 5 are FDA-approved with multiple Phase 3 trials (semaglutide, tirzepatide, liraglutide, tesamorelin, and bremelanotide), while several of the most heavily marketed, including BPC-157, epithalon, and MOTS-c, have zero completed human efficacy trials. This index grades only the strength and quantity of human clinical evidence for each peptide. It is an evidence-cartography tool, not a treatment guide: a high tier means a molecule has been studied in well-designed human trials, not that it is effective for what it is marketed for. “Studied for” describes the research question a trial asked, never an outcome.

Why grade evidence at all? In clinical medicine, the question “is there good human data?” always comes before “does it work?”, and the answer lives on a spectrum. A large Phase 3 randomized controlled trial in thousands of people counts for far more than a single small pilot, which counts for far more than an animal study, which counts for far more than anecdote or a registry entry for a trial that has not finished. Peptide marketing routinely collapses that spectrum: a rat result is repeated until it sounds like a clinical fact, and a recruiting trial is described as if it were completed evidence. Grading each peptide by the highest level of completed human evidence it actually has is how a physician keeps that honest.

How this site grades peptides, in one sentence: we ask what is the most rigorous finished human evidence on record for each molecule. FDA approval with multiple Phase 3 trials is Tier A, completed human RCTs without U.S. approval is Tier B, pilot or small-study human data is Tier C, and animal or laboratory evidence only is Tier D. Trial counts are approximate and point-in-time; the tier is firm. A peptide never moves up a tier because of marketing, patient testimonials, or a registered-but-unfinished study. If you want the deeper safety and FDA-status context for any of these, see our physician-reviewed guides on which peptides are FDA-approved, whether peptide therapy is safe, and the FDA peptide compounding status tracker.

An evidence grade is not a prescription — but it shapes how a thoughtful physician builds your plan. A Tier A medication is one where dosing, expected benefits, and risks have been measured in thousands of people, so Dr. Kamen can plan around real numbers and monitor you against known benchmarks. A Tier B peptide may be appropriate when its human RCT data aligns with your situation and an FDA-approved alternative does not fit. Tier C is a calculated, monitored adjunct at most; Tier D is, in most cases, worth skipping until the human evidence catches up to the marketing.

Practically, that means the grade informs three things: whether something is offered at all, how it is monitored if it is, and what you are told to expect. We do not sell a checkout cart of “stacks.” If a heavily marketed peptide is Tier D, you will hear that directly — along with what an evidence-based alternative looks like for your goals. Care starts with an $88 evaluation and is built around your labs, history, and the actual state of the science — not what is trending on social media. For the full service overview, see physician-supervised peptide therapy.

The evidence on this page does not change by ZIP code — but the marketing pressure absolutely does. Las Vegas has one of the densest concentrations of med-spa, concierge, and direct-to-consumer peptide offerings in the country, and the most aggressively advertised molecules (BPC-157, MOTS-c, epithalon) are very often the ones with the weakest human evidence. That is the gap this index exists to close: a single, physician-maintained map of what has actually been studied in people, so a Las Vegas patient can tell the difference between a proven medication and a hypothesis with a price tag.

Whether you visit our southeast Las Vegas clinic at Eastern Avenue and the 215 from Henderson, Summerlin, Green Valley, or anywhere in the valley — or meet Dr. Kamen by secure telehealth across Nevada — the grading conversation is identical: what the research shows, what tier it sits in, and what that means for your specific goals. No hype, no “research use only” injectables, no stacks sold by the bundle. Just an honest, board-certified read on the evidence. Visit our Las Vegas peptide clinic to start.

• Cerovecki T, et al. Pentadecapeptide BPC 157 (PL 14736) improves ligament healing in the rat. J Orthop Res. 2010;28(9):1155-1161.
• Bock-Marquette I, et al. Thymosin beta4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair. Nature. 2004;432(7016):466-472.
• Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). N Engl J Med. 2021;384(11):989-1002.
• Jastreboff AM, et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial. N Engl J Med. 2023;389(6):514-526.
• Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci. 2018;19(7):1987.

Anchors for specific evidence notes only — preclinical, mechanistic, and trial-design context. Not a treatment claim. Many peptides in this index are not FDA-approved; individual results vary and nothing here is medical advice.