Mile High Compounds FDA Warning Letter: Letter 721600

Updated August 23, 2026

Mile High Compounds LLC of Clifton, Colorado received FDA warning letter 721600, dated March 31, 2026. The agency posted the letter to its public index on April 7, 2026, alongside six other letters to research-peptide sellers signed the same day. The full letter text is public.

The action

On March 31, 2026, FDA signed a warning letter to Mile High Compounds LLC of Clifton, Colorado — letter number 721600. The agency posted it a week later, on April 7, as part of a seven-letter release naming research-peptide sellers in six states. Mile High Compounds is the batch's only Colorado recipient; the remaining letters went to companies in Florida, Arizona, California, Michigan, and Illinois. The batch as a whole is documented at the April 2026 batch record.

The letter itself is published on FDA's site, and its address encodes the record: the company name, the number 721600, and the date suffix 03312026. That page, not this one, is the primary document; it is linked under Sources.

What the batch documents

Across the seven letters, the agency's findings sort into two categories. One is written: therapeutic-effect descriptions on the product pages of compounds sold under research-use labels. The other is structural, and newer as an evidentiary method: the letters cite carts in which administration supplies were offered next to the compounds themselves, the pairing itself counting as evidence of intended use with nothing written down.

The disclaimer question

Research-use-only disclaimers appear across the recipients' sites, and the letters take a direct position on them. Quoted from the batch: despite such disclaimers, "evidence obtained from your website establishes that your products are intended to be drugs for human use."

Coded names, recorded at batch level

Some listings in the batch replaced standard compound nomenclature with coded designations; "GLP-1 SM" and "GLP-3 RT" are the two examples the record preserves. Per the letters, FDA read the practice as circumvention. The examples are batch-level — this index does not tie either name to Mile High Compounds or to any other named recipient.

Record summary

Scale of the action

For context inside this index's own record: FDA's previous multi-recipient action against research-peptide sellers, dated December 10, 2024, named four companies. The March 31, 2026 signing named seven. On the dates this index tracks, no warning-letter action in the category has been larger, and none has reached more states at once.

Limits of the record

No response deadline for this batch is captured in this index, and no account of Mile High Compounds' conduct after March 31, 2026 appears here — the verified record ends with the letter. The company's entry, together with the other six recipients', is kept in the vendor index.

Sources

1. FDA Warning Letter, Mile High Compounds LLC, 721600-03312026. fda.gov
2. FDA Warning Letters index. fda.gov
3. Policy Canary analysis of the batch. policycanary.io

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