Peptide Intel
Regulatory updates, research breakdowns, and market intelligence.
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Regulatory Updates
The 503A Bulk Substances List: What It Is, What's On It, and What Gets Left Off
Explain what 503A means, how a compound gets nominated vs. evaluated, which peptides made the list, and why BPC-157 and...
3 min · 2026-06-18
RegulatoryWhat 2026 FDA Enforcement Signals Mean for the Peptide Compounding Market
Look at 2025 enforcement patterns, pending FDA guidance documents, political environment for pharmaceutical regulation u...
3 min · 2026-06-06
RegulatoryThe FDA's Warning Letter Pattern: Which Peptide Vendors Are Getting Targeted and Why
Analyze FDA enforcement patterns from 2022-2024. What triggers a warning letter, what language gets companies targeted,...
4 min · 2026-05-26
RegulatoryRFK Jr. Moves to End FDA Peptide Ban: What 14 Compounds and a July Deadline Mean
Health Secretary Kennedy announced on Joe Rogan's podcast that FDA will remove 14 peptides from its do-not-compound list. FDA has since formally scheduled a July 23-24 PCAC meeting. Here's what's actually happening and what it means for prescribers.
7 min · 2026-05-26
RegulatoryFDA-Approved Peptides: The Complete List (2026)
A comprehensive, evidence-grounded list of every FDA-approved peptide and peptide-based drug — what it does, what it's approved for, and how it compares to the compounded versions circulating online.
10 min · 2026-05-15
RegulatoryFDA Advisory Panel to Review Seven Peptides in July 2026: What Prescribers Need to Know
The FDA's April 2026 notice announced a July advisory panel review of BPC-157, TB-500, AOD-9604, Thymosin Alpha-1, CJC-1295, Ipamorelin, and Epithalon. Here's what the review means, what outcomes are possible, and what practitioners should watch for.
7 min · 2026-05-13
RegulatoryThe GLP-1 Compounding Crackdown: What Prescribers and Patients Need to Know
The FDA removed semaglutide and tirzepatide from shortage lists in 2024, triggering the end of legal compounding. Here's what happened, what the enforcement timeline looks like, and what comes next.
8 min · 2026-01-10
RegulatoryBPC-157 Regulatory Status in 2025: What Changed and What It Means
BPC-157 was never on the FDA's 503A bulk substances list and FDA actions have repeatedly targeted vendors. Here's a clear-eyed look at the legal status, why clinicians continue to use it, and the risk calculus.
6 min · 2026-01-08
RegulatoryThe Regulatory Status of Research Peptides: A Practitioner's Primer
503A, 503B, the bulk substances list, research-only, FDA-approved — what do these terms actually mean for practitioners prescribing peptides?
9 min · 2026-01-03
Research Deep Dives
Semax and the Russian Bioregulator Tradition: What Western Practitioners Need to Know
Semax is approved in Russia for stroke and cognitive impairment. Review the ACTH fragment mechanism, the Russian RCT dat...
3 min · 2026-07-04
ResearchEpithalon: Evaluating a Decade of Russian Peptide Research
Epithalon (Epitalon) comes almost entirely from one Russian research group (Khavinson). Assess the telomerase activation...
3 min · 2026-07-02
ResearchDihexa: Strong Animal Data, Zero Human Trials — What That Means for Practitioners
Dihexa shows 10-million-fold potency over BDNF in rodent models. Cover the mechanism (HGF/MET signaling), why no company...
3 min · 2026-06-30
ResearchThe GLP-1 Cardiovascular Data: LEADER, SUSTAIN-6, SELECT — What Practitioners Should Know
Break down the MACE data from the major GLP-1 cardiovascular outcome trials. Why SELECT (sema for CV prevention in non-d...
3 min · 2026-06-25
ResearchAOD-9604: GH Fragment Lipolysis, Fat Loss Mechanism, and the IGF-1 Side Effect Distinction
AOD-9604 is a modified fragment of human growth hormone (hGH 176-191) that retains lipolytic activity without stimulating IGF-1. Here's the mechanism, the Phase II/III history, and what the evidence actually supports.
4 min · 2026-05-23
ResearchCagriSema: Cagrilintide + Semaglutide, Phase III Data, and Weight Loss vs GLP-1 Monotherapy
CagriSema combines the amylin analog cagrilintide with semaglutide in a single weekly injection. Phase III REDEFINE 1 showed 22.7% weight loss — substantially exceeding semaglutide alone. Here's the mechanism behind the additive effect and the clinical implications.
4 min · 2026-05-23
ResearchCJC-1295 + Ipamorelin: GH Secretagogue Synergy and the Dosing Rationale
CJC-1295 and Ipamorelin are frequently stacked for growth hormone optimization. The synergy is mechanistically real — two complementary pathways, amplified pulsatility, cleaner GH profile than exogenous hGH. Here's the pharmacology.
4 min · 2026-05-23
ResearchEpithalon: Telomere Extension, Pineal Peptides, and the Longevity Hypothesis
Epithalon is a synthetic tetrapeptide derived from epithalamin, a pineal gland extract. Russian researchers have studied it for decades across aging models. Here's what the data shows — and where it remains speculative.
4 min · 2026-05-23
ResearchFOXO4-DRI: Senolytic Mechanism, the p53/FOXO4 Interaction, and Healthspan Data
FOXO4-DRI is a D-amino acid retro-inverso peptide that disrupts the FOXO4-p53 interaction in senescent cells, triggering apoptosis. The 2017 Nature paper is landmark-level. Here's the mechanism and what followed.
4 min · 2026-05-23
ResearchHumanin: Mitochondrial-Derived Peptide, Insulin Sensitization, and Neuroprotection
Humanin is a 21-amino acid peptide encoded in the mitochondrial 16S rRNA gene — not the nuclear genome. It's one of the first characterized mitochondria-derived peptides (MDPs) with documented roles in neuroprotection, insulin sensitization, and aging.
4 min · 2026-05-23
ResearchKPV: The Alpha-MSH Fragment with a Gut Inflammation Case and Unusual Oral Bioavailability
KPV is a tripeptide fragment of alpha-MSH that retains the parent molecule's anti-inflammatory properties in a form small enough to survive oral delivery. The IBD animal data is solid. Human translation remains the open question.
3 min · 2026-05-23
ResearchSelank: Anxiolytic Mechanism, GABAergic Modulation, and the Cognitive-Mood Profile
Selank is a synthetic analog of tuftsin with registered anxiolytic use in Russia. Its GABAergic mechanism overlaps with benzodiazepines but without the tolerance and dependence profile. Here's the evidence breakdown.
4 min · 2026-05-23
ResearchSemax: Neuroprotection, BDNF Upregulation, and the Cognitive Enhancement Evidence
Semax is a synthetic ACTH analog developed in Russia with registered medical use for stroke and cognitive impairment. The BDNF upregulation mechanism is well-documented. Here's what the clinical record actually contains.
4 min · 2026-05-23
ResearchTB-500 (Thymosin Beta-4): Wound Healing, Soft Tissue Repair, and the Actin Axis
TB-500 is a synthetic analog of thymosin beta-4, a ubiquitous actin-sequestering protein with documented roles in wound healing, angiogenesis, and soft tissue regeneration. Here's what the evidence actually shows.
4 min · 2026-05-23
ResearchThymosin Alpha-1: The Most Clinically Validated Peptide You've Probably Never Prescribed
TA1 is approved in 35+ countries for HBV and HCV. Cover the immune mechanism, the RCT data from sepsis and COVID researc...
3 min · 2026-05-23
ResearchThymosin Alpha-1: Immune Modulation, Thymic Peptides, and the Chronic Infection and Cancer Adjuvant Evidence
Thymosin Alpha-1 is a 28-amino acid thymic peptide with registered use in over 35 countries for hepatitis B/C and immunodeficiency. Its cancer adjuvant data and COVID-19 trial results add a modern dimension to a well-established compound.
4 min · 2026-05-23
ResearchNNMT: The Enzyme Driving Obesity — and Why Inhibiting It May Be the Next Fat Loss Frontier
NNMT is overexpressed in obese fat tissue and actively worsens metabolic health by depleting NAD+ precursors and disrupting the epigenetic machinery that keeps adipocytes healthy. Inhibiting it produces fat loss without caloric restriction in animal models. Here's the science.
6 min · 2026-05-22
ResearchSS-31 (Elamipretide): The Mitochondria-Targeted Peptide with Phase II Heart Failure Data
Break down the EMPOWER-HF Phase II trial, the mitochondrial cardiolipin mechanism, and why Stealth BioTherapeutics' fail...
3 min · 2026-05-21
ResearchMOTS-c and Longevity: Separating the Mitochondrial Science from the Anti-Aging Claims
MOTS-c is a mitochondrial-derived peptide with legitimate basic science behind metabolic regulation and exercise mimicry...
3 min · 2026-05-19
ResearchGHK-Cu in Dermatology: Reading Past the Marketing
GHK-Cu has legitimate peer-reviewed RCT data for skin aging. Separate what the clinical trials showed from the supplemen...
4 min · 2026-05-17
ResearchBPC-157 and Gut Health: Reviewing the IBD and NSAID Injury Evidence
BPC-157's strongest preclinical evidence is gut-related. Cover the stomach pentadecapeptide origin, colitis models, NSAI...
3 min · 2026-05-16
ResearchRetatrutide: The Triple Agonist After Tirzepatide and What the Phase II Data Shows
Eli Lilly's LY3437943 hits GLP-1, GIP, and glucagon receptors. Cover the SURMOUNT Phase II results, weight loss %, and h...
3 min · 2026-05-14
ResearchSemaglutide vs. Tirzepatide: What the Latest Head-to-Head Data Actually Shows
Compare STEP vs SURMOUNT trial outcomes, weight loss %, cardiovascular endpoints, tolerability profiles. No marketing sp...
3 min · 2026-05-13
ResearchHow Ercle Rates Peptide Evidence: Our Methodology
We use a four-tier evidence rating system. Here's exactly what each rating means, what disqualifies compounds from higher ratings, and why we rate the way we do.
5 min · 2026-01-05
Clinical
CJC-1295 with DAC vs. Without: Understanding the Half-Life Tradeoff
The DAC modification extends half-life from minutes to days. Cover the pharmacokinetic tradeoff, blunted pulsatile GH re...
3 min · 2026-07-09
ClinicalPeptide Stability and Storage: The Pharmacist's Perspective on What Actually Matters
Practical guide: lyophilized vs. reconstituted stability, temperature sensitivity by peptide class, light degradation, b...
3 min · 2026-07-07
ClinicalGonadorelin vs. HCG for Testosterone Optimization: The Regulatory and Clinical Case
HCG shortage + compounding restrictions pushed practitioners toward gonadorelin. Cover the mechanism differences (GnRH p...
3 min · 2026-06-23
ClinicalPeptide Stacking: What the Evidence Supports vs. What's Pure Speculation
Practitioner guide: which combination protocols have any mechanistic rationale, which are extrapolated from single-compo...
3 min · 2026-06-20
ClinicalSermorelin vs. Ipamorelin: Which GHRH/GHRP Combination Makes Clinical Sense
Mechanistic comparison of GHRH vs. GHRP pathways, pulsatile GH release, IGF-1 response, half-lives, clinical dosing prot...
3 min · 2026-06-11
ClinicalPT-141 (Bremelanotide): What the RECONNECT Trials Showed and Who It's Actually For
Break down the FDA approval for HSDD, the RECONNECT Phase III data, who responds, cardiovascular contraindications, and...
3 min · 2026-06-09
ClinicalRetatrutide Phase 3 Results: TRIUMPH-1, TRANSCEND-T2D-1, and the Full Picture
Retatrutide hit 28.3% average weight loss in TRIUMPH-1, reduced knee OA pain by 73%, cut sleep apnea severity by 61%, and drove normoglycemia in nearly half of T2D patients. The full Phase 3 dataset is now in.
9 min · 2026-06-06
ClinicalThe Best Fat Burning Peptides in 2026: Evidence-Ranked
A ranked, evidence-based guide to the most effective fat burning peptides available in 2026 — from FDA-approved GLP-1s with 20%+ weight loss to research-stage compounds. Regulatory status and access included for each.
7 min · 2026-05-27
ClinicalFat Loss Peptides: Mechanisms, Evidence, and What Practitioners Need to Know
How do fat loss peptides actually work? A mechanism-first breakdown of GLP-1 agonists, GH secretagogues, direct lipolytic fragments, and metabolic enzyme inhibitors — with honest evidence grading for each.
8 min · 2026-05-27
ClinicalPeptides and Weight Loss: What Actually Works, What Doesn't, and How to Think About It
A practitioner-level breakdown of how peptides affect weight loss — from FDA-approved GLP-1s with 20%+ body weight reduction to research-stage compounds like AOD-9604 and 5-Amino-1MQ. Evidence tiered and clearly labeled.
9 min · 2026-05-27
ClinicalSemaglutide vs. Tirzepatide: Which One Is Right for Your Patient?
Beyond the trial numbers: a practical prescribing framework for choosing between semaglutide and tirzepatide based on patient profile, tolerability, cost, cardiovascular history, and 2026 availability.
7 min · 2026-05-27
ClinicalThe Complete GLP-1 Class Comparison: Semaglutide vs. Tirzepatide vs. Retatrutide vs. CagriSema
A practitioner-focused breakdown of the GLP-1 drug class as of 2025: mechanism differences, efficacy comparisons, safety profiles, and what the pipeline looks like.
12 min · 2026-01-12