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. Of the 450 active UK sellers we audit, 38 (8%) publish their own verifiable Janoshik certificate of analysis, and this page lists which of them hold one covering IGF-1 LR3, newest certificate first. It is a record of paperwork, not a recommendation: The Peptide Watch sells nothing, takes no money from sellers and links to none of them. 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. Purity and identity cannot be judged by eye, so an independent certificate you can check is the only real proof of what is in the vial.

The one test that matters for IGF-1 LR3

Ignore the marketing. The question is simple: does the seller publish a verifiable Janoshik certificate that names the seller itself as the client? If it does, you can confirm an independent lab tested that batch. If it shows an in-house document, a borrowed certificate, or "COA on request", you cannot. Learn the two-minute check in how to verify a Janoshik COA.

Which UK sellers publish a verifiable COA

Of the 450 active UK research-peptide sellers we audit, only 38 (8%) publish their own verifiable Janoshik certificate. Any of them is where you can actually verify testing, for IGF-1 LR3 or any compound. A few: Lab77Peptides · Peptology Labs · Biovanta · Camo Chem · Biohackpeptides · Zenic Labs. See the full independently-tested list, or check a specific shop's certificate with the free COA Checker.

Verified UK vendors with a confirmed IGF-1 LR3 Janoshik certificate (3)

1. Ascendpeptidesuk ascendpeptidesuk.com · newest IGF-1 LR3 report 7 Apr 2026 · task #125388
2. Kensingtonlabs kensingtonlabs.co.uk · newest IGF-1 LR3 report 4 Nov 2025 · task #85944
3. Xlpeptides xlpeptides.com · newest IGF-1 LR3 report 28 Jan 2025 · task #56756

Audit findings, not recommendations. Every entry is a report covering IGF-1 LR3 that we opened on Janoshik's own site and that names the seller itself as the client; the date is the analysis date printed on the report where we have read it, otherwise the date the laboratory received the sample. The table below is the same ledger in full, so the two always agree. Not exhaustive: a vendor whose IGF-1 LR3 report we have not yet read is not listed.

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.

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. 1 of the 3 is 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.

Questions people ask

IGF-1 LR3 in the UK at a glance

Counted from the vendor ledger at build time: a seller is included when its audit records IGF-1 LR3 in its certificates or its catalogue notes. Audit findings, not recommendations.

The other 4 sellers: what they publish instead

• No named lab, nothing to verify: 3
• No lab named: 1

Each pattern is explained on the seller's own audit page, with what we saw and the date. The A-Z directory lists every seller.

The market for IGF-1 LR3 in the UK

Advertising. Google's Ads Transparency Centre shows 1 of these sellers running ads: Kensingtonlabs. Paid reach is where a new buyer meets a brand before meeting any certificate.

Companies. 3 of the 7 can be matched to a Companies House record; the median company is 1.9 years old and 1 was incorporated within the last year. A seller with no traceable company is not necessarily dishonest, but there is nobody to hold to its certificate.

Reviews. 2 of the 7 have a Trustpilot profile with a score; the median is 4.5, 1 sit at 4.5 or above and 0 below 3.0. A review score says who collects reviews, not who tests, which is why it sits next to a certificate and never instead of one.

Changes among IGF-1 LR3 sellers

• 2026-10-01 Best-Peptides (best-peptides.net) added to the audit on the watch list.
• 2026-09-29 Peptides.net (peptides.net) added to the audit on the watch list.
• 2026-09-15 Ascendpeptidesuk (ascendpeptidesuk.com) published a newer own-name certificate (now Apr 2026).
• 2026-09-15 Xlpeptides (xlpeptides.com) published a newer own-name certificate (now Apr 2026).
• 2026-09-15 Kensingtonlabs (kensingtonlabs.co.uk) published a newer own-name certificate (now May 2026).

From the site changelog, which also runs as a JSON feed.

What the research shows for IGF-1 LR3, and what it does not

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.

Who owns IGF-1 LR3, and where it stands

Counts are from PubMed on 15 September 2026 using the queries recorded in our evidence file; "clinical trial" is PubMed's own publication-type index. This is a description of the published record, not medical advice and not an argument for or against use.

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.

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