Immune & Thymic

Discovered by Immunologists, Repurposed by Horse Trainers, and Now It May Be a Prodrug

Alpha-MSH's Anti-Inflammatory Fragment — And It May Work Completely Differently Than Everyone Thinks

Thymic peptide approved in some countries for hepatitis and immune modulation.

Six Human Clinical Trials. 900+ Participants. Safety Indistinguishable From Placebo. Primary Fat Loss Endpoint Failed. WADA Banned. FDA Rejected for Compounding. The Community Uses It Anyway at Doses That Never Worked in the Trials.

GlaxoSmithKline Halted Their Own Drug in 2007 Because It Caused Cancer in Every Animal Species They Tested. The Community Is Still Using It. The Drug Worked. That Is the Entire Problem.

More Clinical Trial Data Than Almost Anything in This Book. Approved in Over 40 Countries. The Largest Independent RCT Failed Its Primary Endpoint. Every Major Positive Trial Has the Manufacturer's Name in the Author List. Cochrane Says: Low to Very Low Evidence.

The Only Senolytic With Real Human Trial Data. Tested at the Mayo Clinic. Proven to Clear Senescent Cells in Humans. Dasatinib Is a Chemotherapy Drug. The Community Is Using It Without Prescriptions, ECGs, or Drug Interaction Screens.

40 Years of Research From One Lab. The Most Cited Telomere Peptide in the Longevity Space. The First Independent Replication Was Published in 2025.

A 2017 Paper Showed It Extended Mouse Lifespan by 24.8%. The Community Is Already Injecting It. There Has Never Been a Human Safety Trial. And It Works by Interfering With p53.

The Most Potent Injectable GHRP. Japan-Approved as a Diagnostic Agent. WADA S2 Banned. The Cortisol Problem That Cuts Against What You're Using It For. The Compound the Community Has Mostly Moved Past — and Why Understanding It Anyway Matters.

The Compound Every Secretagogue in This Book Targets. 191 Amino Acids. FDA-Approved for GH Deficiency, HIV Wasting, Short Bowel Syndrome. July 2025: Skytrofa Once-Weekly Now Approved for Adults. The Pulsatile vs Continuous GH Exposure Distinction. IGF-1 as the Surrogate Marker. The Fake HGH Crisis. WADA S2 Absolute Ban. Why Secretagogues (Sermorelin, Ipamorelin, MK-677) Are Different. The Active Malignancy Hard Stop. The Cancer-IGF-1 Question That Never Goes Away.

Found in Surviving Brain Cells of an Alzheimer's Patient. Encoded in Mitochondrial DNA. Higher in Centenarians' Children. Inversely Correlated With IGF-1. The GH Axis the Community Raises for Anti-Aging Suppresses It.

Four Organ-Specific Bioregulators from the Russian Khavinson Research Tradition. The Theory That Short Peptides Regulate Gene Expression in a Tissue-Specific Way. Cortexin: A Russian-Approved Neuroprotective Extract with Multi-Receptor Activity. CardioCytogen (Ala-Glu-Asp-Arg): The Cardiac Fibroblast Modulator. Crystagen: Connective Tissue and Cartilage Bioregulator. Bronchogen: Pulmonary Bioregulator Tetrapeptide. The Shared Evidence Architecture That Applies to All Four.

40+ Years of Russian Research. 500+ Publications. One Institution. The Most Concentrated Single-Lab Provenance of Any Compound Class in This Book. Vladimir Khavinson (1946-2024) and the St. Petersburg Institute of Bioregulation and Gerontology. The Epigenetic Chromatin Mechanism. The Cytomax vs Cytogen Distinction. The 6-to-8-Year Mortality Study. The 2025 Independent Replication That Changed the Evidence Conversation. 14 Organ-Specific Bioregulators — Their Sequences, Targets, Evidence, and Protocols.

NOT a Peptide — An Amino Acid Quaternary Ammonium Compound. The Most Commercially Overstated Compound in This Book. Genuine Grade B Evidence for Neuropathy (ALCAR), Peripheral Artery Disease (PLCAR), Muscle Recovery (LCLT), Male Infertility (L-Carnitine), and Post-MI Cardiac Outcomes. The TMAO Safety Question. Why Using the Wrong Form Explains Half the Negative Trials. FDA-Approved for Dialysis-Related Carnitine Deficiency.

Every Cell Makes It. Every Major Disease Depletes It. Oral Supplementation Below 1% Bioavailability in Standard Form. IV Delivery With Documented Fatalities. A Billion-Dollar Skin Whitening Industry Built on Mixed Evidence. The Precursor Strategy That Outperforms the Molecule Itself.

⚠ NAMING COLLISION: 'Lipo-C' is used for TWO completely different products — this chapter covers the compounded MIC+L-Carnitine+B-vitamins lipotropic injection. Liposomal Vitamin C (a separate oral supplement also called 'Lipo-C') is covered in a separate chapter. Read Section 1 before proceeding. Lipo-B Extended: Adds L-Carnitine, Thiamine (B1), and Dexpanthenol (B5) to the Lipo-B MIC+B12 base. Zero RCTs for the combination. L-Carnitine Injectable Dose is 100-200x Below Oral Therapeutic Doses. Mechanistically Coherent. Clinically Unproven.

The Only Human Cathelicidin. Antimicrobial, Anti-Biofilm, Pro-Angiogenic, Immunomodulatory, Wound-Healing. Phase IIb Clinical Evidence in Chronic Wounds. Overexpressed in Rosacea, Ovarian Cancer, Breast Cancer, Lung Cancer, Melanoma. Tumor-Suppressive in Colon and Gastric Cancer. The Most Contextually Bidirectional Compound in This Book. Vitamin D Is Its Most Important Natural Inducer.

FDA-Approved. EMA-Approved. The First Effective Treatment for a Disease That Traps Patients Indoors. The Compound That Tans Without UV. The Nevi Darkening Warning the Community Ignores. The Melanoma Question That Has No Clean Answer. The Widest Gap in This Book Between the Disease It Was Made For and the Use It Is Actually Known For.

The Soviet-Era Parkinson’s and Depression Compound Hiding in Limitless’s Catalog. A Tripeptide That Blocks Opioid Effects, Sensitizes D2 Dopamine Receptors, and Has a 5-Day Plasma Half-Life. The Research That Ceased When the Soviet Union Collapsed. What the 2010 Khan et al. Brain Activation Paper Actually Found. NOT the Same as MIF (Macrophage Migration Inhibitory Factor). Why “Melanocyte-Inhibiting Factor” Is a Historical Misnomer.

The Only Oral Compound in This Book That Reliably Raises GH and IGF-1. GHSR-1a Agonist: Not a SARM. The Merck Story: Six Indications, No NDA, Program Discontinued. IGF-1 Goes Up. Fat-Free Mass Goes Up. Strength Doesn't Follow. Glucose Does Go Up. Appetite Definitely Goes Up. The CHF Signal in Elderly Patients. FDA October 2024 PCAC: No Compounding. WADA S2. The Water Weight Trap. Why Sleep Quality Is the Most Reliable Benefit. The Community's Most Misunderstood Compound.

The Exercise-Mimetic Peptide Encoded in Mitochondrial DNA — Revolutionary Biology, Zero Human Intervention Trials, WADA Banned at All Times.

The Drug That Was Going to Treat Leaky Gut and Celiac Disease — And How the Phase 3 Trial Ended. What Zonulin Actually Is and Why Tight Junction Regulation Is Hard to Measure. Four Phase 2 RCTs: Symptom Improvement With Gluten Challenge. The Phase 3 Discontinuation in 2022. The N-Acetyl Modification That Limitless Sells: What It Adds and What It Doesn’t Change. How This Differs From BPC-157 and KPV in the Gut Stack.

Tuftsin → Selank → N-Acetyl Selank Amidate: Three Generations of Molecular Engineering. Russian-Approved Anxiolytic Without Sedation, Without Tolerance, Without Dependence. Comparable to Benzodiazepines for GAD With Psychostimulant Properties They Lack. BDNF Upregulation. Enkephalin Stabilization. The Evidence Is for Selank. NASA Is the More Stable Delivery Format Whose Equivalent Efficacy Is Chemically Logical but Clinically Unproven.

ACTH Fragment Without the Cortisol Effect. Russia's Premier Nootropic-Neuroprotective Peptide. Approved for Stroke, Encephalopathy, Optic Nerve Atrophy, Cognitive Disorders. BDNF Upregulation 50-300% in Hippocampus and Frontal Cortex. Default Mode Network Changes by fMRI. 71% vs 41% Memory Test Accuracy in Fatigued Volunteers. Half-Life Extended from 3-5 Minutes (Semax) to 4-6 Hours (MASA) by N-Acetyl and Amidate Modifications.

The Most Legitimate Longevity Target in This Book. The Most Commercially Weaponized. The Man Promoting NMN Has Financial Ties to NMN. The Man Criticizing Him Has Financial Ties to NR. The Clinical Evidence Is Real and More Modest Than Either Side Tells You.

FDA-Approved at 50 mg for Opioid and Alcohol Use Disorder Since 1984. Off-Label at 1.5-4.5 mg (LDN) — Two Completely Different Mechanisms at Two Completely Different Doses. TLR4 Blockade on Microglia. The Endorphin Rebound. A Lancet Rheumatology RCT in 2024. An Evidence Base Growing Faster Than Pharma Has Any Reason to Fund. The Most Favorably Tolerated Prescription Drug in Its Evidence Literature.

Cancer-Selective Membrane Pore Formation. MDM2 on the Surface of Cancer Cells as the Target. No Phase 1 Human Trials. No FDA Review. No Human Safety Data. Used by Cancer Patients as Last Resort. The Most Ethically Complex Chapter in This Book. What the Evidence Actually Shows. What It Cannot Show. Why Active Cancer Patients Must Read This Chapter Before Any Self-Administration Decision.

The Compound Designed to Kill Cancer Cells by Forming Pores in Their Membranes. The Reversal: Active Malignancy Is the Designed Use Context. How MDM2 on Cancer Cell Surfaces Creates the Selectivity Mechanism. p53 AA17-26 + Penetratin: What Each Domain Does. PNC-27 vs PNC-28: The Structural Difference and Whether It Matters. In Vitro Human Cancer Cell Data and In Vivo Mouse Model Evidence. The Community Off-Label Use Question.

The Selectivity Claim That Doesn't Hold Up in the Only Published Human Trial. Phase 1 Breast Cancer Study: 59% Elevated AST, 45% Elevated ALT. Six or More Published DILI Case Reports — Including Near-Transplant Cholestatic Hepatitis. HPTA Suppression: As Real as Testosterone. WADA S1.2 Absolute Ban. FDA Warnings. The 53% Problem: Only Half of SARM Products Contain What They Claim. Why 'Fewer Side Effects Than Steroids' Doesn't Mean Safe.

The ITP Mouse Data: Lifespan Extended at Multiple Labs, Doses, and Start Ages. The PEARL Trial (April 2025): First 48-Week Placebo-Controlled Human Longevity Trial Published. The Bioavailability Finding That Changes Everything: Compounded Rapamycin Is ~3x Less Bioavailable Than Commercial. Intermittent vs Continuous Dosing: The Pharmacological Divide Between Transplant Medicine and Longevity Use. The Immunosuppression Risk That Needs Honest Framing. The Drug Interaction Profile That Makes This the Most Dangerous Compound in This Book to Stack. Why the Community Uses ~6 mg Weekly. What Happens When You Stop.

Russia Approved It. The West Has Never Independently Validated It. And It Might Be the Only Anxiolytic That Doesn't Make You Stupid.

Russia Uses It for Stroke. The West Uses It for Morning Focus. The Evidence Is Strong for One of Those. Guess Which.

The Metabolically Active Member of a Six-Peptide Family From the Same Mitochondrial Gene as Humanin. A Receptor Has Been Found. An Obesity Protection Mechanism Has Been Identified. Lower Levels Are Associated With Prostate Cancer Risk. No Human Trial Has Been Run.

Not a Peptide. 70% Endurance Gain in Mice. Zero Human Trials. WADA Banned Before Anyone Had Studied It in a Human.

The Only FDA-Approved Mitochondrial Therapeutic. Most Clinical Trials Failed. The Basic Science Is Compelling. All Three of These Things Are True Simultaneously.

is not evidence quality — it is scope appropriateness

KLOW is mechanistically the most comprehensive tissue repair protocol in this book — four non-overlapping mechanisms covering angiogenesis, cell migration, ECM remodeling, and inflammatory suppression simultaneously. The tension: comprehensiveness is not the same as superiority. Adding a fourth compound means: more injections (or more complex blended vial formulation); more copper accumulation risk on extended cycles (GHK-Cu); more cost; and more moving parts when something doesn't work as expected. For many users, GLOW already covers their needs; KLOW is the right choice when the inflammatory dimension or gut protection is a specific priority. The chapter exists to clarify when KLOW is worth the additional complexity.

First Signaling Peptides Derived from the Mitochondrial Genome

Most Widely Used Peptide Healing Combination in Community History

Approved in 37+ Countries. The Most Extensively Studied Thymic Peptide in Clinical Medicine. 30+ RCTs. 11,000+ Subjects. HBeAg Seroconversion RR 2.31. A Positive Sepsis Trial in 2013 Followed by a Definitive Negative Phase 3 in 2025. The US Regulatory Rollercoaster: Category 2 (2023) → Nomination Withdrawn (2024) → Pending PCAC Review (2026). Immunomodulator, Not Immunostimulant — A Critical Distinction.

The Only Thymic Hormone That Requires a Metal Cofactor. Biologically Inactive Without Zinc. The Most Important Clinical Point: Zinc Deficiency Causes Functional Thymulin Deficiency — And Zinc Supplementation Restores It. One Human Interventional Study from 1982. Extensive Animal Evidence. The Chapter That Is Also a Zinc Education.

NOT a Fragment of TA1 — the Full 28-Amino-Acid Thymosin Alpha-1 with an RGDR Tumor-Targeting Sequence Appended. The RGDR Motif Binds Integrin αvβ3 Overexpressed on Tumor Vasculature. A Chinese Pharmaceutical University Research Construct Designed to Concentrate TA1’s Immune Activation at Tumor Sites. What the Lao 2013 and Peng 2020 Papers Actually Show. The Community Use Question: Why a Cancer-Targeting Construct Is in General Use. What Companion Chapter pbta1v4 Covers vs What This Chapter Covers.

The Most Physiologically Broad Compound in This Book. 28 Amino Acids. Every System in the Body. VPAC1 and VPAC2. The 90-Second Half-Life Problem That Blocked IV Use. How Intranasal Administration Changed Everything. Dr. Shoemaker's CIRS Protocol: 300+ Physicians, 90%+ Symptom Reduction. The Long-COVID Connection. Aviptadil COVID ARDS Trials. The Mast Cell / MCAS Intersection. Why the Community Uses It and What the Evidence Actually Shows.