“Research Use Only” Is Not a Legal Shield — and Prosecutors Have Used It as Evidence

The regulation that decides it

The controlling text is 21 CFR § 201.128. It does not ask what the label says. It asks what the seller objectively intended, and it lists the evidence that can show it:

Read that last clause carefully. The regulation expressly reaches uses for which a product is neither labelled nor advertised. A disclaimer cannot defeat a test that was drafted to look past labels in the first place.

What FDA actually writes in the letters

FDA has rejected the disclaimer in near-identical language across a wave of warning letters. The clearest formulation came in the December 2025 letter to Pinnacle Peptides:

The phrase including your website is doing the work. The same reasoning appears in the February 2025 letter to USApeptide.com, where labels said “research use only” while the site described semaglutide as an approved injectable for weight loss; and in the June 2026 letter to Wholesale Peptide, where “RESEARCH USE ONLY” sat alongside claims that a product “reduces chronic inflammation” and treats an enlarged prostate. Three further letters issued on a single day in March 2026.

What counts as a claim

• Product pages, blog posts, FAQs, dosing charts and protocol guides
• Customer testimonials and before/after content
• Email marketing, social media, and affiliate copy
• SEO text written for human-use search terms, even on a separate page
• The composition and packaging itself — injectable-format vials sold with bacteriostatic water and syringes are “circumstances surrounding the distribution”

The part that turns a misdemeanour into a felony

This is the mechanism most sellers do not understand, and it is where the disclaimer actively harms them.

A plain FDCA violation is a strict-liability misdemeanour. Prosecutors rarely stop there. Adding intent to defraud triples the exposure — and a disclaimer the seller knows to be false is close to ideal proof of exactly that state of mind. The seller wrote down, in their own packaging, a statement they knew did not describe what they were doing.

How it has played out

United States v. Kawa (Paradigm Peptides) — sentenced July 2026

Matthew Kawa received 70 months in prison and a $5,000,000 money judgment; a co-defendant received 16 months. The operation ran 2019–2024 and reached more than 54,000 customers across all 50 states and 80-plus countries. His plea admitted he knew the products were marketed for human consumption despite the “research use only” labelling. FDA had sent warning letters in 2020 and 2022; both were ignored.

Government testing also found that many products sold as SARMs actually contained testosterone — a Schedule III controlled substance. That single fact converts a pure drug-approval case into potential controlled-substance exposure, whatever the vendor believed they were shipping.

United States v. Brown (Warrior Labz) — sentenced February 2025

Brown claimed “research purposes only” and “not for human consumption” while simultaneously making structure/function benefit claims. DOJ characterised the claim as false — the internal contradiction between the disclaimer and the marketing was the evidence of intent. He continued selling after a June 2023 FDA warning letter; three undercover buys followed.

United States v. DeFranco — the clearest statement

Older, but the cleanest articulation of the point. DOJ described DeFranco as having “deceived the Internet service provider and the FDA by falsely representing on the website that he was selling these substances ‘for research purposes only … not for human consumption.’” The disclaimer was not treated as a defence raised and rejected. It was charged as part of the deception, supporting mail fraud and money laundering counts alongside the drug offences.

What actually gets charged

1. Unapproved new drug — 21 U.S.C. §§ 331(d), 355(a). The workhorse count.
2. Misbranding — § 331(a)/(c)/(k), with § 352(f)(1) (no adequate directions for use) and § 352(b) (labelling omissions).
3. The felony escalator — § 333(a)(2), intent to defraud or mislead.
4. Smuggling — 18 U.S.C. § 545, where product is imported.
5. Mail and wire fraud, money laundering — 18 U.S.C. §§ 1341, 1343, 1956/1957.
6. Forfeiture — routinely large relative to the custodial sentence.

The short version

• Intended use is decided by conduct, not labels — 21 CFR § 201.128.
• FDA reads your website as labelling. It says so, in those words, in letter after letter.
• The disclaimer does not reduce exposure. Where it is knowingly false it tends to increase it, by supplying the intent element that makes the offence a felony.
• Aggravators that turn a civil matter criminal: ignoring prior warning letters, false claims about FDA registration or domestic manufacturing, forged certificates of analysis, mislabelled shipping, and downstream patient harm.

For where a specific compound stands, see our peptide database or the United States regulation page.