FDA Warning Letters to Research Peptide Sellers

On 24 August 2026 the FDA sent warning letters to five online peptide vendors, including Peak Performance Peptides and NuScience Peptides. Each sold products with research labels. Law firm ArentFox Schiff put the message in six words: "The RUO label is not protection."

Why did the research use label fail?

The FDA judged the products by the sellers' websites. Its letter to Peak Performance Peptides says: "Despite statements on your product labeling marketing your products for 'research use only' and 'not for human consumption,' evidence obtained from your website establishes that your products are intended to be drugs for human use."

What did the FDA say about bacteriostatic water?

It treated the water as evidence of intended use. The Peak Performance letter says marketing it as a solvent meant "providing the means to prepare an injectable drug for human administration". That letter also lists "Bac water" itself as an unapproved new drug.

Did the letters mention peptide calculators?

Yes. The NuScience letter calls a "peptide calculator" sold alongside the water "a resource that provides the means to prepare an injectable drug for human administration". The letter to Royal Peptides cites a calculator and a "peptide guide".

Does this apply in Australia?

No. These are US letters under US law. Australian rules sit with the Therapeutic Goods Administration, covered in our Australian legal guide. For the US position, see are peptides legal in the US.

Research use only

Peptide Labs supplies research peptides strictly for in-vitro laboratory use, not for human or animal use. This article reports public news and gives no use or dosing guidance.

Sources

• •FDA letter to Peak Performance Peptides
• •FDA letter to NuScience Peptides
• •FDA letter to Royal Peptides
• •ArentFox Schiff, 18 September 2026