FDA Category 2 Designations for Peptides (2023-2024)

This is a historical record. None of these peptides is on FDA’s Category 2 list today. The designations described below were unwound in April 2026, when the nominations were withdrawn and the substances were removed from Category 2. They were not moved to Category 1 — most now appear in no interim category at all, and that is still not permission to compound: a substance in no category is not on the 503A bulks list either. The current Category 2 list contains exactly six substances, none of them peptides on this page. For today’s position see FDA-503A-Category-System and regulatory-timeline-2024-2026.

Between 2023 and 2024, the FDA placed a wave of popular therapeutic peptides on the Category 2 bulk drug substances list, effectively prohibiting their compounding under Section 503A of the Federal Food, Drug, and Cosmetic Act.

Affected Compounds

The following peptides were designated as Category 2 at the time (cannot be compounded under 503A). All were removed from Category 2 in April 2026:

• BPC-157 — body protection compound, used for tissue repair and gut healing
• TB-500 (Thymosin Beta-4) — wound healing and anti-inflammatory peptide
• CJC-1295 — growth hormone releasing hormone analog
• Ipamorelin — selective growth hormone secretagogue
• GHRP-2 — growth hormone releasing peptide
• GHRP-6 — growth hormone releasing peptide
• AOD-9604 — anti-obesity drug fragment of hGH
• Melanotan II — synthetic melanocortin peptide

What Category 2 Means

Under the FDA-503A-Category-System, the FDA evaluates bulk drug substances nominated for use in compounding and places them into categories:

• Category 1 — “Under Evaluation”: FDA “does not intend to take action … provided that the conditions described in the guidance are met.” That is enforcement discretion while an evaluation is pending, not approval — and it is not the same as being on the 503A bulks list. Do not read Category 1 as “approved for compounding.”
• Category 2: FDA has determined these substances raise significant safety risks and intends to take action; they cannot be compounded under 503A
• Category 3: Nominated without adequate supporting information for FDA to evaluate — also not on the bulks list, also no lawful compounding route

A Category 2 designation means compounding pharmacies are prohibited from preparing these peptides for patients, even with a valid prescription. This does not make the peptides illegal to possess but removes the legal pathway for pharmacies to prepare them.

Rationale

The FDA cited several concerns in its Category 2 designations:

• Insufficient safety data: Most of these peptides lack completed Phase III clinical trials
• No FDA-approved reference drug: Unlike compounded versions of approved drugs (e.g., compounded semaglutide during shortage), these peptides have never been FDA-approved
• Quality concerns: Peptides sourced from grey-market suppliers often lacked adequate purity testing
• Adverse event reports: The FDA received reports of adverse reactions, though the quality of reporting varied

Impact on the Market

The Category 2 designations had immediate and far-reaching effects:

1. Compounding pharmacies were forced to stop preparing these peptides, losing a significant revenue stream
2. Patients who relied on compounded peptides for chronic conditions lost legal access
3. Grey-market vendors saw increased demand as patients sought alternative sources with no quality oversight
4. Telehealth peptide clinics had to restructure their offerings or shut down
5. Research chemical vendors became the de facto supply chain, operating in a legal grey area

Timeline

Related Notes

• FDA-503A-Category-System — explanation of the category framework
• FDA-Reclassification-Announcement-Feb-2026 — Kennedy’s proposed reversal
• Peptide-Sciences-Shutdown-March-2026 — grey-market vendor closure