Peptides Loosen, GLP-1 Compounding Tightens — The FDA’s Two Opposite Tracks

If you have read this year that “the FDA is loosening the rules on peptides” and, in nearly the same breath, that “the FDA is moving to ban compounded GLP-1s,” you have not misread a contradiction. Those are two separate regulatory tracks moving in opposite directions, on different lists, over different substances, through different legal mechanisms. Vendors have every incentive to blur them into a single “peptides are being legalized” story. They are not the same story, and this piece keeps them apart.

The one thing to carry away first: removing a peptide from the FDA’s Category 2 list is not authorization to compound it. The twelve peptides removed in April were not moved into Category 1 and were not placed on the 503A compoundable list. They sit in a regulatory gray area pending further action. Nothing is legal to compound today that wasn’t legal yesterday.

Track 1 — Peptides generally: loosening

On April 16, 2026, the FDA published a Federal Register notice (Docket No. FDA-2025-N-6895) and, in a parallel action, removed twelve peptide bulk substances from Category 2 — the “significant safety concern” list — because their nominations had been withdrawn. Those twelve are the ones the agency is now routing through its Pharmacy Compounding Advisory Committee (PCAC) for possible inclusion on the 503A Bulks List, split across two meetings:

• Reviewed July 23–24, 2026 (seven): BPC-157, KPV, TB-500, MOTS-c, Epitalon, Semax, and Emideltide (DSIP).
• Slated for a second PCAC meeting, expected by the end of February 2027 (five): GHK-Cu, Melanotan II, Cathelicidin LL-37, Dihexa, and pegylated Mechano Growth Factor (PEG-MGF).

At the July meeting, the committee voted to recommend six of the seven peptides for the 503A list — BPC-157, KPV, TB-500, MOTS-c, Epitalon, and Semax, on 8–6 and 7–5 splits — and rejected DSIP. We covered the tallies in detail in our vote recap. The important framing bears repeating: a PCAC vote is a non-binding recommendation, not an approval. For any of the six to actually become compoundable, the FDA must still act — realistically through notice-and-comment rulemaking, with HHS sign-off — a process observers expect to run into 2027. The direction of this track is toward broader access. It has not arrived.

Track 2 — GLP-1 drugs specifically: tightening

On April 30, 2026, the FDA proposed to exclude semaglutide, tirzepatide, and liraglutide from the 503B Bulks List — the roster of substances that federally registered outsourcing facilities may compound in bulk on a finding of “clinical need.” The agency said it found no such need. The notice was published in the Federal Register on May 1, 2026.

Two precision points, because “proposed” and “banned” are different words. First, this is a proposal, not a final rule. The comment period was originally set to close at the end of June and was then extended to July 30, 2026. As of early August, that window has closed and the FDA is weighing comments; no final determination has been issued. Second, exclusion from the 503B list would close the clinical-need route to bulk compounding — but it would not, by itself, foreclose bulk compounding “regardless of shortages.” A separate pathway remains: if any of these drugs returns to the FDA drug-shortage list, outsourcing facilities may compound it while the shortage lasts. That pathway is currently dormant — the tirzepatide shortage resolved in October 2024 and the semaglutide shortage on February 21, 2025 — but it is a conditional door, not a sealed one.

Why these two tracks are not a contradiction

They touch different lists and different substances. Track 1 concerns research peptides and the 503A framework (patient-specific compounding by a licensed pharmacy). Track 2 concerns three approved GLP-1 drugs and the 503B framework (large-scale compounding by outsourcing facilities). A peptide can be moving toward the 503A list while a GLP-1 is moving off the 503B list with no inconsistency at all — they are separate rosters maintained under separate statutory tests. The through-line is not a single direction of travel; it is that the FDA is drawing sharper lines around what may be compounded, and where.

A third layer: the states

Federal compounding status is not the only rulebook. States regulate the practice of pharmacy and medicine directly, and in 2025–2026 the great majority of state action has targeted GLP-1 compounding specifically rather than peptides in general. Medical boards in New York, California, Texas, and Florida have brought disciplinary actions against telehealth-only weight-loss operations, and states including California, Michigan, and New York have issued their own guidance on compounded GLP-1s. Some of that activity cuts the other way — several states have eased telehealth prescribing of these drugs by dropping in-person-visit requirements — which is precisely the point: state law and federal compounding status are separate questions that can diverge. The clearest peptide-broad exception is Louisiana’s SB 253, effective August 1, 2026, which bars state boards from prohibiting authorized providers from supplying patients with peptides shipped from FDA-registered 503A/503B facilities. It is the outlier that proves the pattern: nearly everything else at the state level has been about GLP-1s.

Questions about the panel that produced the peptide votes

The peptide track’s advisory votes came from a committee that was largely reconstituted just before the meeting. Eight of the twelve PCAC members were appointed on June 29, 2026, and by the reporting of STAT News and the Associated Press, six of the eight run wellness, longevity, or regenerative-medicine clinics that prescribe peptides. Named examples include Dr. Haleem Mohammed, who operates the Gameday Men’s Health clinic chain; Dr. Gabriel Alizaidy, who charges for peptide and hormone consultations and promotes BPC-157 and GHK-Cu online; and Bobby Harshbarger, a Tennessee state senator and pharmacist at his family’s compounding pharmacy. The FDA’s own meeting roster is public. HHS has said the members underwent standard ethics review and that, where conflicts existed, waivers were granted on a “broad sector interest” basis. Both characterizations are on the record; readers can weigh them.

What this means for the research community

The two tracks send one combined signal, and it is not “peptides are now legal.” On the peptide side, an advisory panel has pointed at where the FDA could go, and the agency has not gone there yet. On the GLP-1 side, the FDA has proposed to narrow bulk compounding and has not finalized that either. Treat any “now legal to compound” or “now banned” claim as premature until the FDA completes rulemaking in each case.

Prof. Peptide’s position is unchanged. We report on these compounds as research chemicals; a compounding recommendation or a bulk-list proposal is a regulatory-process event, not a safety, efficacy, or approval determination. Nothing here should be read as a statement that any of these substances is safe, effective, or approved for human use. We’ll update this article as the FDA acts on either track.