Where to buy IGF-1 LR3 (Long R3 IGF-1) in the UK: the sellers with a verifiable COA
The newest verifiable IGF-1 LR3 certificate on any UK seller's website is on Ascendpeptidesuk (ascendpeptidesuk.com), analysed 7 Apr 2026 (task #125388 on Janoshik's site); 3 verified sellers hold one covering IGF-1 LR3, listed newest first below.
A record of paperwork, not a recommendation: The Peptide Watch sells nothing, takes no money from sellers and links to none of them.
Who has the newest report · Why the date matters · What purity means · What IGF-1 LR3 is · Regulators · Every report
Who holds the newest IGF-1 LR3 report (3 verified UK sellers)
Newest report first. Every report was opened on Janoshik's own website and names the seller as the client. The date is the analysis date printed on the report. The verify link opens the laboratory, never the shop. Audit findings, not recommendations.
| Seller | Newest IGF-1 LR3 report | Age of that report | Purity on it | |
|---|---|---|---|---|
| Ascendpeptidesuk | 7 Apr 2026 | 6 months, 6 days | 97.756% | verify |
| Kensingtonlabs | 4 Nov 2025 | 11 months, 9 days | 99.083% | verify |
| Xlpeptides | 28 Jan 2025 | 20 months, 15 days | 99.386% | verify |
Every IGF-1 LR3 purity report we have read (3), one row per report
The 3 verifiable IGF-1 LR3 certificates we have read, newest first
Each row was opened on Janoshik's own site by a real page load and transcribed. The client column is the name the laboratory printed; a certificate counts as a seller's own only when that name is the seller. The report date is the analysis date printed on the report where we have read it, otherwise the date the laboratory received the sample. The verify link opens the laboratory, never the shop. Audit findings, not recommendations.
| Seller | Task | Client on the report | Report date | Result | Batch | |
|---|---|---|---|---|---|---|
| Ascendpeptidesuk | #125388 | Ascend Peptides UK | 7 Apr 2026 | IGF-1 LR3 · 1.14 mg · 97.756% | 20260114 | verify |
| Kensingtonlabs | #85944 | Kensingtonlabs.co.uk | 4 Nov 2025 | IGF-1 LR3 · 1.29 mg · 99.083% | IGF-371DK | verify |
| Xlpeptides | #56756 | XL Peptides | 28 Jan 2025 | IGF-1 LR3 · 1.02 mg · 99.386% | 007001 | verify |
Why the date on a certificate matters
What a purity figure means
The purity on a Janoshik report is the share of the main peak in an HPLC chromatogram. 99.5% means that 99.5% of what the detector saw was one substance and 0.5% was something else. It is not the amount in the vial: that is the separate quantity line, in milligrams. It does not by itself prove which substance the peak is: that is identity, confirmed by mass spectrometry. And it says nothing about sterility, endotoxins or heavy metals, which are separate tests.
A purity figure printed on a shop page with no report behind it is a claim, not a measurement. Between two reports, the difference that matters is rarely 99.2% against 99.8%; it is whether the report exists at all, names the seller as the client, covers this compound on its own, and is recent.
What IGF-1 LR3 is, and what it is sold as
IGF-1 LR3 is a laboratory analogue of insulin-like growth factor 1 built in Adelaide in the late 1980s so it would not bind the body's IGF-binding proteins. It was made as a cell-culture reagent, has no clinical trials and no licence, and is banned in sport; the licensed IGF-1 medicine, mecasermin, is a different product.
| Development status | Never in clinical development. Never in human trials. Made as a cell-culture growth factor. |
|---|---|
| Originator | GroPep Pty Ltd, Adelaide (a University of Adelaide and CSIRO spin-out), late 1980s, as a laboratory growth factor. Rights: GroPep's patents have expired; the reagent is sold by several biotechnology suppliers. No medicine developer. |
| Registered clinical trials | 0 on ClinicalTrials.gov |
A cell-culture reagent, sold as an injection. Long R3 IGF-1 is insulin-like growth factor 1 with an arginine swapped in at position 3 and a 13-amino-acid extension, built by GroPep in Adelaide, a University of Adelaide and CSIRO spin-out, in the late 1980s so that it would not be captured by the body's IGF-binding proteins. Its purpose was to grow cells in bioreactors and to study growth in animals. PubMed indexes 118 papers, 47 in rodents and none a clinical trial; ClinicalTrials.gov lists no study. The most recent animal study, in growth-restricted fetal sheep in 2025, found no growth effect.
IGF-1 itself is a medicine; the LR3 analogue is not. Mecasermin (Increlex), recombinant human IGF-1, was approved by the FDA on 30 August 2005 and by the European Commission in August 2007 for children with severe primary IGF-1 deficiency, and is listed as a UK product. LR3 has never been submitted anywhere, and the 2026 WADA Prohibited List bans IGF-1 and its analogues at all times. The one human safety fact that transfers is the medicine's own warning: IGF-1 causes hypoglycaemia.
What a certificate can tell you. One report, from XL Peptides in January 2025, recovered 1.02 mg at 99.386% purity on a 1 mg label.
The published record in numbers, and the sources
| Papers on PubMed | 118 |
|---|---|
| Indexed as rat or mouse studies | 47 |
| Indexed as clinical trials | 0 |
| Published since 2020 | 11 |
Counts are from PubMed on 15 September 2026 using the queries recorded in our evidence file. A description of the published record, not medical advice and not an argument for or against use.
- Anabolic effects of insulin-like growth factor-I (IGF-I) and an IGF-I variant in normal female rats. (J Endocrinol, 1993, PMID 8371075)
- IGF-1 LR3 does not promote growth in late-gestation growth-restricted fetal sheep. (Am J Physiol Endocrinol Metab, 2025, PMID 39679943)
- Measurement of an analog of insulin-like growth factor-I in blood plasma using a novel enzyme-linked immunosorbent assay. (J Endocrinol, 1998, PMID 9582496)
- The emerging landscape of performance-enhancing peptides modulating GH-IGF1 axis: bridging the gap between clinical evidence and patient self-administration. (Front Endocrinol (Lausanne), 2026, PMID 42395176)
- European Medicines Agency, Increlex (mecasermin) product information
- USADA, IGF-1 and the WADA Prohibited List
- WADA, 2026 Prohibited List (S2: peptide hormones, growth factors, related substances and mimetics)
- electronic medicines compendium, UK product search for mecasermin
What regulators say about IGF-1 LR3
In the UK. Not a licensed medicine. The licensed IGF-1 is mecasermin (Increlex), a prescription-only medicine for a rare childhood condition.
We hold no statement from the FDA, MHRA or EMA specifically about IGF-1 LR3 on file. Its development and licence sources are listed under the record above.
What the 3 IGF-1 LR3 certificates show
We have read 3 Janoshik reports covering IGF-1 LR3, published by 3 UK sellers. Each was opened on Janoshik's own website. All 3 name the seller itself as the client. 0 of the 3 are dated within the last six months and 1 is more than a year old. The newest is dated 7 Apr 2026 and the oldest 28 Jan 2025.
All 3 reports give a purity figure for IGF-1 LR3. The figures run from 97.756% to 99.386%, and 2 of the 3 are at 99% or above. A purity figure describes the sample the laboratory received, not every vial from that batch.
Read directly from the newest reports: Ascendpeptidesuk: task #125388, analysed 7 Apr 2026, 1.14 mg recovered at 97.756%, client Ascend Peptides UK; Kensingtonlabs: task #85944, analysed 4 Nov 2025, 1.29 mg recovered at 99.083%, client Kensingtonlabs.co.uk; Xlpeptides: task #56756, sample received 28 Jan 2025, 1.02 mg recovered at 99.386%, client XL Peptides.
A certificate is a batch document. The lines that matter are the compound (it must say IGF-1 LR3, not only a batch code), the client (the shop, not its supplier) and the analysis date. A new batch is untested until a new report appears.
IGF-1 LR3 in the UK at a glance
| Active UK sellers listing IGF-1 LR3 | 8 |
|---|---|
| Of which publish a verifiable own-name certificate | 3 |
| Of which name no laboratory at all | 3 |
Counted from the vendor ledger at build time. The A-Z directory lists every seller and what each publishes instead.
Questions people ask
Which UK sellers publish a verifiable Janoshik certificate naming IGF-1 LR3?
As of 13 October 2026, 3: Ascendpeptidesuk, Kensingtonlabs, Xlpeptides. Each has a report on Janoshik's own website that names the seller as the client and lists IGF-1 LR3. That is a statement about paperwork, not a recommendation; The Peptide Watch does not recommend anywhere to buy IGF-1 LR3.
How recent is the newest IGF-1 LR3 certificate from a UK seller?
The newest we have read is Janoshik task #125388, analysed 7 Apr 2026. It is published by Ascendpeptidesuk and names it as the client. A certificate covers one batch, so an old one says little about stock on sale today.
How do I check that a certificate for IGF-1 LR3 is genuine?
Four things: an independent laboratory is named; the client field names the seller you are buying from, not a supplier; the compound line says IGF-1 LR3; and the report's task number and key open the same report on the laboratory's own website (verify.janoshik.com). A branded PDF with no laboratory name and no verification code fails on the first check, however professional it looks. The free COA Checker on this site runs the checks for you.
Is IGF-1 LR3 a licensed medicine in the UK?
Not a licensed medicine. The licensed IGF-1 is mecasermin (Increlex), a prescription-only medicine for a rare childhood condition. Never in human trials. Made as a cell-culture growth factor. The Peptide Watch does not give legal or medical advice.
Why does The Peptide Watch not say where to buy IGF-1 LR3?
Because the site records paperwork, not recommendations. A verifiable certificate proves that a sample of one batch was tested. It does not prove the vial you receive matches it, and it says nothing about whether anyone should use IGF-1 LR3. Listing which sellers publish a certificate you can check, and which publish nothing, is as far as the evidence goes.
The Peptide Watch's position on IGF-1 LR3
Not a licensed medicine. The licensed IGF-1 is mecasermin (Increlex), a prescription-only medicine for a rare childhood condition. The Peptide Watch reads the certificates UK sellers publish and does not recommend anywhere to buy IGF-1 LR3. Sellers on this page are listed by the date of their newest IGF-1 LR3 certificate and by nothing else. If you can verify a seller's testing, you can at least judge its evidence; if you cannot, you are taking the seller's word for what is in the vial. See how UK testing compares across every seller in the market statistics.
An honest note: a verifiable certificate proves a sample of a batch was tested, not that the specific vial you receive matches it, see what this can and can't tell you. The Peptide Watch sells no IGF-1 LR3 and links to no shop; this is research-use-only information, not medical or dosing advice.
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