Regulatory Sensitivity Matrix
Sorted by sensitivity descending. High-sensitivity entries include POM-adjacent compounds (GLP-1 agonists, PT-141) and combinations using them.
Educational research-literacy content only. Not medical advice, not dosing guidance, not sourcing advice, and not a protocol for human or animal use. See our responsible information policy.
Regulatory sensitivity flags compounds and stacks that attract — or are likely to attract — MHRA scrutiny under the medicinal-product definition or POM advertising rules. High sensitivity means a UK or US/EU prescription-only medicine is in the combination, active enforcement against public-facing UK marketing exists, or both.Moderate means an unapproved compound with credible medicinal claims; low means a compound with limited regulatory exposure as currently positioned. This is not a legal opinion. See UK regulation hub, POM advertising rules, borderline products.
| Compound / stack | Approval | Sensitivity | Note | |
|---|---|---|---|---|
| Peptide | Cagrilintide — Long-Acting Amylin Analogue (Research Evidence Summary) | not-approved | high | No standalone UK MHRA approval as of 2026-07. Investigational only; used almost exclusively in the CagriSema fixed-ratio combination programme with semaglutide. Not authorised for prescription or supply in the UK. Any weight-loss framing of cagrilintide in advertising falls under the POM-medicine advertising rules the MHRA applies to GLP-1s. |
| Peptide | Cerebrolysin — Porcine-Brain Neuropeptide Preparation | not-approved | high | Approved as a medicinal product in 40+ jurisdictions including Austria, Russia, China, Czech Republic, Mexico (post-stroke + cognitive indications). NOT licensed in UK or US — MHRA Special Authorisation required for UK import. Laboratory research use only outside approved territories. |
| Peptide | GHRP-2 — Growth Hormone Releasing Peptide 2 (Research Evidence Summary) | not-approved | high | Not UK-approved. Pralmorelin (GHRP-2) has been used as a diagnostic agent for GH deficiency in Japan but is not licensed in the UK. Research-grade material is permissible for laboratory use only. WADA-prohibited at all times. |
| Peptide | Melanotan II — Broad-Spectrum α-MSH Analogue | not-approved | high | Unapproved globally. MHRA enforcement priority for sales presented as a tanning agent for human use. Research and laboratory use only — never sell as cosmetic, supplement, or for human administration. |
| Peptide | MK-677 (Ibutamoren) — Oral Ghrelin-Receptor Agonist (Research Evidence Summary) | not-approved | high | No UK MHRA marketing authorisation. Not approved by the FDA or EMA. Development for indications including growth hormone deficiency and osteoporosis was not carried through to marketing. Listed by the World Anti-Doping Agency (WADA) as a prohibited substance in-competition and out-of-competition. Sold as a research chemical; any human-facing framing falls under UK medicines-advertising rules. |
| Peptide | PT-141 (Bremelanotide) — MC4R-Selective Melanocortin Agonist | unclear | high | FDA-approved as Vyleesi (2019) for premenopausal HSDD. Not licensed in UK by MHRA — research use only outside US. |
| Peptide | Retatrutide — Triple GIP/GLP-1/Glucagon Receptor Agonist | unclear | high | Phase III ongoing (2026). Unapproved globally as of May 2026. Research-grade material is unapproved for human medicinal use. |
| Peptide | Semaglutide — GLP-1 Receptor Agonist (Research Evidence Summary) | approved | high | UK MHRA approved. Wegovy (semaglutide 2.4 mg weekly SC) is approved for chronic weight management in adults with obesity or overweight with comorbidities. Ozempic (semaglutide 0.5–2 mg weekly SC) is approved for type-2 diabetes. Rybelsus (oral semaglutide) is approved for type-2 diabetes. All formulations are prescription-only medicines (POM). |
| Peptide | Tesamorelin — Stabilised GHRH Analogue (EGRIFTA) | unclear | high | FDA-approved (EGRIFTA, 2010) for HIV-associated lipodystrophy. EU/UK availability limited. Outside this indication, research use only. |
| Peptide | Thymosin α-1 — Thymic Immunomodulatory Peptide (Zadaxin / Thymalfasin) | not-approved | high | Approved as a medicinal product in 30+ countries (Zadaxin/Thymalfasin) for hepatitis B and C, primarily Italy, China, Mexico, Argentina. NOT approved in UK or US — research use only. |
| Peptide | Tirzepatide — Dual GIP/GLP-1 Receptor Agonist (Mounjaro / Zepbound) | approved | high | UK MHRA licensed (Mounjaro) for type 2 diabetes and obesity. FDA-approved as Mounjaro (T2DM) and Zepbound (chronic weight management). Research-grade material falls outside the licensed product authorisation. |
| Stack | BPC-157 + KPV + Thymosin α-1 — Research Evidence Review: Immune & Mucosal Mechanisms | not-approved | high | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | CJC-1295 + Ipamorelin + Tesamorelin — Research Evidence Review: GH Axis Mechanisms & Study Limitations | not-approved | high | Direct combination evidence is limited (mostly preclinical / small-trial). |
| Stack | CagriSema (Semaglutide + Cagrilintide) — Research Evidence Review (UK POM sensitivity, investigational) | unclear | high | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Cerebrolysin + Semax — Research Evidence Review: Neuropeptide & BDNF-Axis Mechanisms | not-approved | high | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Melanotan II + Bremelanotide — Research Evidence Review: Melanocortin Mechanisms & Safety Signals | not-approved | high | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | PT-141 + Kisspeptin-10 — Research Evidence Review: Melanocortin & Reproductive-Axis Mechanisms | not-approved | high | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Tesamorelin + AOD-9604 — Research Evidence Review: Visceral Adipose Research Context | not-approved | high | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Tirzepatide + Retatrutide + AOD-9604 — Research Evidence Review: Incretin & Lipolytic Mechanisms (UK POM sensitivity) | unclear | high | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Peptide | AOD-9604 — Growth Hormone C-terminal Lipolytic Fragment | not-approved | moderate | Granted GRAS status in the US (food/cosmetic), not approved as a medicinal product. Unapproved in UK/EU for therapeutic use. Research use only. |
| Peptide | BPC-157 — Body Protection Compound 157 | not-approved | moderate | Unapproved research compound in UK (MHRA), US (FDA) and EU (EMA). For in vitro laboratory research only. |
| Peptide | CJC-1295 — GHRH(1-29) Analogue (no DAC / DAC variants) | not-approved | moderate | Unapproved research compound in UK, US, EU. Laboratory research use only. Distinct from medicinally-approved Tesamorelin. |
| Peptide | DSIP — Delta Sleep-Inducing Peptide | not-approved | moderate | Unapproved research compound in UK, US, EU. Laboratory research use only. |
| Peptide | Epitalon — Pineal Tetrapeptide Bioregulator | not-approved | moderate | Khavinson group has medicinal-product approval for related bioregulators in the Russian Federation. Epitalon itself remains an unapproved research compound in UK, US, EU. |
| Peptide | GHK-Cu — Copper Tripeptide-1 | not-approved | moderate | Topical cosmetic use legal in UK / EU / US (multiple commercial dermal products). Injectable research-grade peptide remains unapproved for human medicinal use. |
| Peptide | Humanin — Mitochondrial-Derived 24-Amino-Acid Peptide | not-approved | moderate | Unapproved research compound globally. Laboratory and in vitro use only. |
| Peptide | Ipamorelin — Selective Growth Hormone Secretagogue | not-approved | moderate | Unapproved research compound globally. For in vitro and laboratory research only. |
| Peptide | Kisspeptin-10 — GnRH-Axis Hypothalamic Decapeptide | not-approved | moderate | Unapproved research compound in UK, US, EU — extensive clinical research (Dhillo, Imperial College) but no marketing authorisation. Laboratory research use only. |
| Peptide | KPV — α-MSH(11-13) C-Terminal Anti-Inflammatory Tripeptide | not-approved | moderate | Unapproved research compound in UK, US, EU. Laboratory and in vitro research use only. |
| Peptide | LL-37 — Human Cathelicidin Antimicrobial Peptide | not-approved | moderate | Unapproved research compound in UK, US, EU. Laboratory and in vitro research use only. |
| Peptide | MOTS-c — Mitochondrial Open Reading Frame 12S rRNA-c | not-approved | moderate | Unapproved research compound globally. Laboratory research use only. |
| Peptide | Pinealon — Pineal Tripeptide Bioregulator | not-approved | moderate | Khavinson group has medicinal-product approval for related bioregulators in the Russian Federation. Pinealon itself remains an unapproved research compound in UK, US, EU. |
| Peptide | Selank — Tuftsin-Derivative Anxiolytic Heptapeptide | not-approved | moderate | Approved in Russian Federation as a medicinal product (anxiolytic indication). Unapproved in UK, US, EU — laboratory research use only. |
| Peptide | Semax — ACTH(4-10) Heptapeptide Nootropic | not-approved | moderate | Approved as a medicinal product in the Russian Federation (essential drugs list, post-stroke + cognitive rehabilitation indications). Unapproved in UK, US, EU — research use only. |
| Peptide | SS-31 (Elamipretide) — Cardiolipin-Targeted Mitochondrial Peptide | not-approved | moderate | Phase III clinical-trial pipeline (Stealth BioTherapeutics) for primary mitochondrial myopathy and other indications. Not FDA/EMA/MHRA-approved as of May 2026. Research-grade material remains research-only. |
| Peptide | TB-500 — Thymosin β-4 (1-4) Synthetic Fragment | not-approved | moderate | Unapproved research compound in UK, US, EU. Laboratory and in vitro research use only. |
| Peptide | Thymalin — Thymic Peptide Complex Bioregulator | not-approved | moderate | Approved as a medicinal product in the Russian Federation. Unapproved in UK, US, EU — research use only. |
| Stack | BPC-157 + GHK-Cu — Research Evidence Review: Follicular Mechanisms & Evidence Limits | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | BPC-157 + TB-500 + GHK-Cu — Research Evidence Review: Tissue-Repair & Remodelling Mechanisms | not-approved | moderate | Direct combination evidence is limited (mostly preclinical / small-trial). |
| Stack | BPC-157 + TB-500 — Research Evidence Review: Tissue-Repair Mechanisms & Translational Limits | not-approved | moderate | Direct combination evidence is limited (mostly preclinical / small-trial). |
| Stack | DSIP + Selank — Research Evidence Review: Sleep & Anxiolytic Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Epitalon + Humanin + MOTS-c — Research Evidence Review: Mitochondrial & Telomeric Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Epithalon + Thymalin — Research Evidence Review: Khavinson Bioregulator Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | GHK-Cu + TB-500 — Research Evidence Review: Dermal Remodelling Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Ipamorelin + CJC-1295 + BPC-157 — Research Evidence Review: GH Axis + Tissue-Repair Mechanisms | not-approved | moderate | Direct combination evidence is limited (mostly preclinical / small-trial). |
| Stack | KPV + LL-37 — Research Evidence Review: Mucosal & Antimicrobial Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | MOTS-c + AOD-9604 — Research Evidence Review: Mitochondrial & Lipolytic Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | SS-31 + Humanin — Research Evidence Review: Mitochondrial Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | SS-31 + MOTS-c — Research Evidence Review: Mitochondrial Cardiovascular Mechanisms | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | Semax + Selank + Pinealon — Research Evidence Review: Neuropeptide Mechanisms & Translational Limits | not-approved | moderate | No direct combination studies; mechanism is inferred from monotherapy literature. |
| Stack | TB-500 + BPC-157 — Research Evidence Review: Tendon Repair Mechanisms & Study Models | not-approved | moderate | Direct combination evidence is limited (mostly preclinical / small-trial). |
Published: 2026-06-20Last updated: 2026-06-20Last reviewed: 2026-06-20
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