Why did Peptide Sciences shut down, and is it still selling?
This is one entry from the TitrateLab Vendor Graveyard, a dated archive of peptide-market shutdowns, buyer-loss reports and enforcement actions. Documented as March 6, 2026. Evidence tier: Documented record. Sources for this entry are linked inline below and annotated in the full Vendor Graveyard entry.
Peptide Sciences shut down on March 6, 2026, calling the decision voluntary, and has not said why. It replaced its storefront at peptidesciences.com with a three-sentence notice that gave no reason and said nothing about open orders or refunds. Web searches of FDA and Justice Department pages on October 11, 2026 found no warning letter, enforcement action or charge naming the company. Nothing we found shows the company selling since. Every Internet Archive capture of its homepage that we read, from March 8 to September 8, 2026, shows the notice and no store, and since at least March 21 the notice has called anyone claiming to sell its products fraudulent. A store using the Peptide Sciences name since the closure is not shown to be the company, and a review of such a store may describe someone else.
Our certificate archive holds 125 results on Peptide Sciences vials dated before the closure, from December 17, 2024 to March 3, 2026. In 14 the laboratory did not find the labelled peptide. All 14 were vials that Finnrick, a testing service, bought itself, and they carry three printed batch codes, two for retatrutide and one for CJC-1295. Where the labelled peptide was present, purity was 98.6% or higher in all 111 results, but 56 of those 111 vials held more than 10% less than the label stated. We measured these figures on October 11, 2026; the method and exclusions are at the end of this entry.
The peptidesciences.com homepage as captured by the Internet Archive on March 8, 2026 at 15:21 UTC, the first capture after the closure (archived page). Screenshot taken by TitrateLab on October 10, 2026.
What the notice said, and how it changed. The March 8 capture shows the whole notice: “After careful consideration, Peptide Sciences has made the decision to voluntarily shut down operations and discontinue the sale of our research products. We are deeply grateful for your trust and support. Thank you for being part of the Peptide Sciences community.” The Peptide List, writing on March 6, quoted the first sentence and said the three-sentence notice appeared at about 2:00 PM Eastern that day.
The captures show two later versions. A March 18 capture still shows the three sentences alone. By March 21 the company had added: “Any website, entity, or individuals claiming to be Peptide Sciences, a successor to Peptide Sciences, or falsely claiming to sell our products are fraudulent, unauthorized, and have absolutely no affiliation with our company. Do not interact with them and report them to us immediately.”
The notice as captured by the Internet Archive on March 22, 2026 at 17:39 UTC (archived page). The same warning is in the March 21, 2026 capture taken at 14:40 UTC, the earliest we read that has it. Screenshot taken by TitrateLab on October 11, 2026.
By April 15 the notice carried the wording it still showed on September 8, the latest capture that shows the page rather than an access block when we checked on October 11. The company now says it “retains all rights, title, and interest in and to its name, brand, trademarks, intellectual property, and associated goodwill”. It adds: “Any website, platform, entity, or individual claiming affiliation with Peptide Sciences, representing themselves as a successor to Peptide Sciences, or claiming to sell our products is unauthorized, fraudulent, and has no affiliation with our company.” Both later versions give an email address for reports on a separate domain, registered in May 2024, before the closure. No version gives a reason, mentions orders or refunds, or names a site the company considers unauthorized.
The current notice as captured by the Internet Archive on September 8, 2026 at 05:07 UTC (archived page). The same wording appears in the April 15, April 18 and May 17, 2026 captures. Screenshot taken by TitrateLab on October 10, 2026.
Why it closed: what is and is not known. The date and the company’s description of the closure as voluntary are documented. The reason is not. A law-firm analysis a week later found “no confirmed public explanation” and noted that “no official enforcement action has been announced”. It reports that some observers read the closure as a sign of regulatory pressure and others as a change in business strategy. The closure came 7 days after Kennedy’s February 27 podcast remark about peptide access, and about five weeks after Science.bio closed on January 27 citing “regulatory compliance reasons”. No version of the Peptide Sciences notice mentions regulation, and no source we hold ties the closure to either event. The Peptide List’s March 6 article says the FDA sent the company a warning letter in 2023 over claims about BPC-157 and TB-500, but it links no FDA record, and a web search of fda.gov on October 11, 2026 found no warning letter addressed to Peptide Sciences. We treat that letter as unconfirmed. We also hold no buyer report showing whether orders open on March 6 were shipped or refunded.
What our certificate archive showed before the closure. These are the 125 results with test dates from December 17, 2024 to March 3, 2026. Finnrick bought 96 of the vials itself; members of the public mailed in 28; one is a Janoshik certificate, test 67573, printed for an anonymous client with the manufacturer name Peptide Sciences.
| Result | Count |
|---|---|
| Labelled peptide not found | 14 of 125 |
| Retatrutide, labelled peptide not found | 10 of 38 |
| CJC-1295, labelled peptide not found | 4 of 10 |
| Purity 99.5% or higher, where the labelled peptide was found | 79 of 111 |
| Amount within 10% of the label | 44 of 111 |
| More than 10% under the label | 56 of 111 |
| More than 35% under the label | 7 of 111 |
| More than 10% over the label | 11 of 111 |
All 10 retatrutide failures sit on two printed batch codes, RET7920231109-6 and RET7920231124-6, which also produced 3 passing results. Six of the 10 failing records name tirzepatide as the peptide the laboratory found instead; the other four say only that the vial did not contain retatrutide or held an unknown compound. Janoshik vs Chromate: Why Peptide Lab Results Disagree reproduces those records, including all eight results on RET7920231109-6, which came from two orders Finnrick placed itself. The other 25 retatrutide results, on other codes or none, all found retatrutide. The 4 CJC-1295 failures share one code, CJC320241122-5, and the 4 results on another code, CJC320250118-5, all found CJC-1295. The other compounds tested were tirzepatide, semaglutide, BPC-157, Melanotan II, ipamorelin, PT-141, GHK-Cu and tesamorelin, and none of their 77 results failed identity.
Finnrick record j7838b4, dated April 22, 2025: a vial sold as 6 mg retatrutide held 4.38 mg of tirzepatide. Screenshot captured by TitrateLab in August 2026.
Results dated after the closure. Ten more Finnrick results filed under Peptide Sciences carry test dates from April 2 to July 20, 2026. Members of the public mailed in all ten, and six did not contain the labelled peptide: three retatrutide, two tesamorelin and one CJC-1295. Three of the ten carry batch codes beginning PS6: PS6HRP22 on a retatrutide vial and on a tesamorelin vial, and PS6HRI22 on a CJC-1295 vial. No code in that format appears among the 125 earlier results, and all three of those vials failed identity. The records do not show where or when each vial was bought, and Finnrick describes four of the ten vials as having no label. The one below was registered as a public shipment on March 16, 2026, ten days after the closure. Ten results are too few to compare with the earlier record. A vial filed under the name could be stock bought before the closure or could come from someone else using it, and the records do not tell us which.
Finnrick record n552547, certificate issued April 28, 2026. Screenshot taken by TitrateLab on October 10, 2026.
A site that used the name after the closure. The domain peptidescienceslabs.com was registered on April 16, 2026, 41 days after the closure, according to its .com registry record, which we queried on October 11, 2026. The only Internet Archive capture of it, from May 16, 2026, shows a storefront titled “Home - Peptide sciences” that calls itself Peptide Sciences, lists research products at prices from $65 to $345 and offers a 15% discount on cryptocurrency orders. On October 11 the registry listed the domain under “client hold” with no name servers, a status a registrar sets to keep a domain from resolving; the record does not say why, and it was last updated on August 13, 2026. We have not established who ran the site. Nothing we hold connects it to the closed company. No version of the company’s notice names it, and the notice’s warning about sites claiming to sell its products was already in place by March 21, before the domain was registered. A Trustpilot page for peptidescienceslabs.com was among Google’s top 10 US results for “peptide sciences review” in Semrush data we pulled on October 5, 2026, so a review found under the name may concern this site rather than the company. Our guide to checking whether a peptide vendor is legit starts with confirming a seller’s exact domain and when it was registered.
peptidescienceslabs.com as captured by the Internet Archive on May 16, 2026 at 21:19 UTC (archived page); the archive did not keep the site’s stylesheets. Screenshot taken by TitrateLab on October 10, 2026. The capture is not evidence of who operated the site.
A certificate shown by any seller using the name says nothing about that seller unless it verifies on the laboratory’s own server and matches the vial in hand. Our guide to verifying a peptide COA lists the checks.
How we measured. We read TitrateLab’s certificate database on October 11, 2026 without writing to it. The count covers results filed on Finnrick’s Peptide Sciences vendor page, which lists peptidesciences.com as the vendor’s website, plus Janoshik test 67573. A result counts as “not found” when the laboratory reported that the vial did not contain the labelled peptide. Finnrick’s results come from laboratories it codes A to G, and laboratories do not measure amount identically, so some of the spread in amounts may come from the laboratory rather than the vial. Public submitters chose what to send. The figures describe the vials tested, not every batch the company sold. Our Peptide Sciences seller page counted 321 certificates on October 11, 2026. That total also includes 134 Finnrick results filed under Peptide-S, a separate Finnrick vendor that lists a different website, 12 filed under a Finnrick vendor called Science, and 40 Freedom Diagnostics reports printed for a client named “Peptides”. None of those records names Peptide Sciences, so we left them out here. We read nine Internet Archive captures of the homepage, dated March 8 to September 8, 2026. The FDA and Justice Department checks were web searches limited to fda.gov and justice.gov; FDA’s own warning-letter search refused our requests, so those searches cannot rule out a letter entirely. The image sources, capture times, registry records and counts are listed in the evidence manifest.
Evidence tier: Documented record.
Sources: Peptide Sciences closing notice, Internet Archive capture of March 8, 2026; notice with added warning, capture of March 22, 2026; current notice, capture of September 8, 2026; The Peptide List, March 6, 2026; LumaLex Law, March 13, 2026; Finnrick Peptide Sciences vendor page; Janoshik test 67573; .com registry record for peptidescienceslabs.com; Internet Archive capture of peptidescienceslabs.com, May 16, 2026; TitrateLab certificate database, read October 11, 2026.