FDA FILEDOCUMENTED

FDA tells five peptide sellers “research use only” labels do not exempt their injectables

DOCUMENTED. FDA posted warning letters on Sept. 1, 2026 (dated Aug. 24) to five peptide sellers, stating that products sold as “research use only” are unapproved new drugs. The letters are FDA’s allegations; each firm was told to respond within 15 business days.

Attribution: Compiled from the five warning letters as posted on FDA’s website and FDA’s warning-letters table, read on October 5, 2026. Quoted phrases are FDA’s. We have not seen any company response.

Allegations in government documents and in reports by others are theirs, not findings by us. Verify against the linked sources. Disclaimer.

By Peptide Industry Gossip · Observed 2026-09-01 · Published 2026-10-05

5 letters

Posted by FDA on Sept. 1, 2026, all dated Aug. 24, 2026, from the Center for Drug Evaluation and Research

505(a)

Section of the FD&C Act the letters cite for selling unapproved new drugs (with 301(d))

15 days

Business days each firm was given to respond in writing

Still online

All five company homepages loaded when we checked on Oct. 5, 2026

What is and is not supported

SUPPORTED

FDA issued warning letters to five peptide sellers

Tex Peptides (Dallas, TX), Royal Peptides (Boynton Beach, FL), NuScience Peptides (Cornelius, NC), Peptide Partners (Sarasota, FL) and Peak Performance Peptides (Phoenix, AZ).

FDA: Tex FDA: Royal FDA: NuScience FDA: Peptide Partners FDA: Peak

FDA ALLEGES

The products are unapproved new drugs sold in violation of the law

FDA cites sections 301(d) and 505(a) of the FD&C Act. These are FDA’s findings from a website review, not a court ruling.

FDA: NuScience

FDA REJECTS

“Research use only” or “not for human consumption” labels change the legal status

Each letter says that despite such labeling, evidence on the firm’s website shows the products are intended as drugs for human use.

FDA: Peak FDA: Royal

NONE LOCATED

The firms have responded publicly

We did not find a response. We did not search outside the FDA pages and the company homepages.

NOT REPORTED

Seizure, injunction or other further action has been taken

The letters warn that failure to address the violations may lead to seizure and injunction. We found no report that either has happened.

OBSERVED

The five firms are still operating

Each homepage loaded on Oct. 5, 2026. We did not check which of the cited products are still listed.

What happened

On Sept. 1, 2026, FDA posted five warning letters dated Aug. 24, 2026, each issued by the Office of Unapproved Drugs and Labeling Compliance in the Center for Drug Evaluation and Research.
The recipients are TXP Innovations LLC dba Tex Peptides, Royal Peptides LLC, NuScience Peptides LLC, Peptide Partners LLC and Peak Performance Peptides. The letters for Peptide Partners and NuScience date FDA’s website review to July 2026.
FDA says the firms offer injectable products it treats as unapproved new drugs and not generally recognized as safe and effective. Products named across the letters include semaglutide, tirzepatide and retatrutide, along with SS-31, PT-141 and tesamorelin; the NuScience letter also names survodutide and mazdutide.
Each letter addresses “research use only” labeling directly: FDA says website evidence shows the products are intended for human use. At least one letter (Peak Performance Peptides) also says the firm markets bacteriostatic water as a solvent for reconstituting its products.
Each firm was told to respond in writing within 15 business days of receipt and warned that failure to address the violations may lead to seizure and injunction.

What we can verify

FDA posted all five letters on its website on Sept. 1, 2026, and its warning-letters table lists them under “Unapproved New Drugs/Misbranded.”
Each letter cites sections 301(d) and 505(a) of the FD&C Act and the 15-business-day response window.
All five company homepages loaded (HTTP 200) on Oct. 5, 2026.

What remains unknown

Whether any of the five has responded to FDA, removed the listed products, or been subject to further action.
Which of the cited products remain for sale; we checked homepages only.
Whether FDA will send similar letters to other sellers. Earlier peptide-seller letters were posted in December 2024, March 2026 and June 2026 (see timeline).

Timeline

Date / time	Event
2024-12-17	FDA posts warning letters (dated Dec. 10, 2024) to four research-peptide sellers: Prime Vitality dba Prime Peptides, Swisschems, Xcel Research and Summit Research Peptides. FDA table
2025-12-23	FDA posts a warning letter (dated Dec. 12, 2025) to Pinnacle Professional Research dba Pinnacle Peptides. fda.gov
2026-04-07	FDA posts five warning letters (dated Mar. 31, 2026) to Lovega dba Pink Pony Peptides, Gram Peptides, Prime Sciences, Mile High Compounds and PekCura Labs. fda.gov fda.gov
2026-06-23	FDA posts a warning letter (dated June 17, 2026) to Wholesale Peptide. fda.gov
2026-07	FDA reviews the websites of NuScience Peptides and Peptide Partners, per those two letters. FDA: NuScience FDA: Peptide Partners
2026-08-24	Date on all five letters: Tex Peptides, Royal Peptides, NuScience Peptides, Peptide Partners and Peak Performance Peptides. FDA: Tex FDA: Royal
2026-09-01	FDA posts the five letters. Each gives the firm 15 business days from receipt to respond. FDA table
2026-10-05	Our check: all five company homepages load. No company response located. texpeptide.com royal-peptides.com nusciencepeptides.com peptide.partners pppepz.com

Locations

Location	What public reporting established
Tex Peptides: Dallas, TX	TXP Innovations LLC dba Tex Peptides. Letter MARCS-CMS 735067. FDA: Tex
Royal Peptides: Boynton Beach, FL	Royal Peptides LLC. Letter MARCS-CMS 734884. FDA: Royal
NuScience Peptides: Cornelius, NC	NuScience Peptides LLC. Letter MARCS-CMS 733652. FDA: NuScience
Peptide Partners: Sarasota, FL	Peptide Partners LLC. Letter MARCS-CMS 735063. FDA: Peptide Partners
Peak Performance Peptides: Phoenix, AZ	Letter MARCS-CMS 735127. FDA: Peak

Participating agencies

Agency	Reported role or presence
FDA Center for Drug Evaluation and Research (CDER)	Issuing center for all five letters, signed by the Director of the Office of Unapproved Drugs and Labeling Compliance, Office of Compliance. FDA: NuScience

Receipts

FDA warning letter: TXP Innovations LLC dba Tex Peptides (Aug. 24, 2026) · captured 2026-10-05 · tier 1
FDA warning letter: Royal Peptides LLC (Aug. 24, 2026) · captured 2026-10-05 · tier 1
FDA warning letter: NuScience Peptides LLC (Aug. 24, 2026) · captured 2026-10-05 · tier 1
FDA warning letter: Peptide Partners LLC (Aug. 24, 2026) · captured 2026-10-05 · tier 1
FDA warning letter: Peak Performance Peptides (Aug. 24, 2026) · captured 2026-10-05 · tier 1
FDA warning letters table (searched for “peptide” on Oct. 5, 2026) · captured 2026-10-05 · tier 1
Tex Peptides homepage, observed Oct. 5, 2026 · captured 2026-10-05 · tier 1
Royal Peptides homepage, observed Oct. 5, 2026 · captured 2026-10-05 · tier 1
NuScience Peptides homepage, observed Oct. 5, 2026 · captured 2026-10-05 · tier 1
Peptide Partners homepage, observed Oct. 5, 2026 · captured 2026-10-05 · tier 1
Peak Performance Peptides homepage, observed Oct. 5, 2026 · captured 2026-10-05 · tier 1

Company response

No company response located as of the publish date.

Why people care

Sellers who label injectable peptides “research use only” have been treating that wording as a legal shield. These letters state FDA’s position that it is not, and they arrive in a run of peptide-seller letters going back to December 2024. Buyers and competing sellers are watching whether any firm changes its listings and whether FDA escalates.

Corrections and update log

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