Category 1, Category 2, 503A, 503B, Approved: The Five Terms That Decide Whether You Can Get a Peptide

The short answer

Five words decide whether a doctor can get a peptide into your hands legally in the United States. Approved means FDA reviewed the finished drug and it can be prescribed. 503A and 503B are the two kinds of compounder, a pharmacy filling individual prescriptions and a larger outsourcing facility, and neither makes anything approved. Category 1 and Category 2 are FDA's interim labels for ingredients that have been nominated for compounding: roughly, "may be used while FDA decides" and "significant safety concerns."

As of September 30, 2026, the peptides most people ask about sit in a narrow gap. Twelve came off Category 2 in April, an advisory committee backed six in July, and none has been added to the list pharmacies need or moved into Category 1. That means no lawful compounding route yet, and the vial sold online as "research use only" was never on any route at all.

Approved: the only status that means FDA reviewed the drug

An approved drug has been through a new drug or biologics application: FDA has reviewed evidence that it works for a defined use, that its benefits outweigh its risks, and that it is made consistently to a set standard. Several peptides have reached that point. Bremelanotide, sold as PT-141 in the grey market, is approved as Vyleesi High; tesamorelin is approved as EGRIFTA High; and elamipretide, the SS-31 of forums, received accelerated approval as Forzinity High.¹

Everything else in this guide is a way of getting an unapproved drug. FDA states it plainly: compounded drugs are not FDA approved, which means the agency does not review their safety, effectiveness or quality before they are marketed.² Compounding can meet real needs, such as a patient who cannot take an ingredient in the approved version, but it is an exception to approval, not a lighter form of it.

503A: a pharmacy, a prescription, and a short list of ingredients

Section 503A of the Food, Drug, and Cosmetic Act covers the traditional compounding pharmacy. A drug compounded under it is exempt from the approval, manufacturing and labeling requirements that apply to ordinary drugs, provided the pharmacy meets the section's conditions; one of them is that it compounds on receipt of a valid prescription for an individual patient.³

The ingredient matters as much as the prescription. A 503A pharmacy may compound from a bulk drug substance only if it has a USP or National Formulary monograph, is a component of an FDA-approved drug, or appears on the 503A bulks list.⁴ That list lives in the Code of Federal Regulations, at 21 CFR 216.23, and it is short: six substances, most of them for topical use, and no peptides. FDA judges candidates on four criteria: how well the substance is characterised, the safety issues it raises in compounded drugs, the evidence of effectiveness, and its history of use in compounding.⁵ Most research peptides have no monograph and are not part of any approved drug, so the bulks list is the only door, and it is closed to them today.

Category 1, 2 and 3: interim labels, not the list

Building the bulks list is slow, so FDA sorts nominated ingredients into three interim categories while it works. The current version of the policy applies to substances nominated before January 7, 2025. Category 1 means a substance is under evaluation and FDA does not intend to take action against a pharmacy compounding with it, if the other conditions in the guidance are met. Category 2 means FDA has identified significant safety risks, so the Category 1 policy does not apply. Category 3 means the nomination lacked enough information to evaluate.⁶

FDA's current categories document, updated May 14, 2026, shows how much has moved. Category 2 now holds six substances. The only peptide among them is kisspeptin-10; ibutamoren Medium, better known as MK-677, is there too, but it is not a peptide. GHK-Cu for non-injected use was added back to Category 1 in May after one nominator clarified that it had meant to withdraw only the injectable form, and FDA says it intends to consult its advisory committee on GHK-Cu before the end of February 2027. GHRP-2 Medium and GHRP-6 sit in Category 3.⁷

A category is not a verdict on whether a peptide works, and it is not a permanent status. Category 1 is enforcement discretion while FDA decides; Category 2 is a safety flag, and it can be lifted without anything replacing it, which is exactly what happened in April.

503B: outsourcing facilities

Section 503B, added in 2013, created a second kind of compounder: the outsourcing facility. Unlike a 503A pharmacy, it must follow current good manufacturing practice, it is inspected by FDA on a risk-based schedule, and it can supply compounded drugs to a hospital or clinic as office stock, without a prescription for a named patient.³ Its products are still not approved.

Outsourcing facilities have their own ingredient rule: they may compound from a bulk substance on the 503B list, which covers substances with a clinical need, or when the finished drug is on FDA's drug shortage list. The rule became the centre of the GLP-1 debate once the shortages ended. On May 1, 2026, FDA published a notice proposing not to add semaglutide High, tirzepatide or liraglutide to the 503B list; none was ever on it.⁸ The comment period was extended to July 30, 2026.⁹ As of September 30, the Federal Register shows no final decision, and our GLP-1 transition hub tracks it.

Three 2026 case studies

April: twelve peptides off Category 2. On April 15, FDA said it would remove twelve peptides from Category 2, effective April 22, because the nominators had withdrawn their nominations: BPC-157 Low, TB-500 Low, KPV Low, MOTS-c Low, emideltide (DSIP) Low, semax Medium, epitalon Low, injectable GHK-Cu, Melanotan II Low, LL-37, dihexa and PEG-MGF.¹⁰ None moved into Category 1. The safety flag was gone, but nothing yet let a pharmacy use them, and FDA's current document still lists none of the twelve in Category 1.⁷

July: six recommendations, one rejection. FDA's Pharmacy Compounding Advisory Committee met on July 23 and 24 to consider seven of the twelve for the bulks list.¹¹ FDA's briefing documents had argued against adding any of the seven.¹² The committee disagreed on six: BPC-157, KPV and TB-500 passed 8 to 6 with one abstention, MOTS-c 7 to 5 with two, and semax and epitalon the next day by similar margins, while emideltide failed 6 to 7.¹³ An advisory vote is advice. FDA's page for the meeting, last updated August 6, carries the agenda, questions and FDA's presentations, but no minutes.¹²

Still none on the list. Adding a substance to 21 CFR 216.23 takes rulemaking, and the regulation as it stood on September 1, 2026 still named six substances and no peptide.⁵ Our search of the Federal Register on September 30 found no 503A bulks action since July. The five peptides the July meeting did not cover wait for a second meeting, due before the end of February 2027.¹⁰ Our PCAC hub has the full record of the July votes and briefing documents.

Where each peptide stands on September 30, 2026

The table uses FDA's categories document of May 14, 2026, the July committee votes as reported, and the regulation as of September 1, 2026. "Pharmacy may compound" means a lawful 503A route exists today, not that a pharmacy will do it or that it is wise.

Approved drugs such as tesamorelin and PT-141 can be compounded only under the ordinary 503A conditions, including a prescription for an individual patient.³ For the full list of 298 compounds and their statuses, see the regulatory tracker.

What this means if you want a peptide

If a peptide is approved, the route is a prescription for the approved product. If it is not, the only lawful route is compounding, and that depends entirely on the ingredient: a 503A pharmacy needs a monograph, an approved-drug component, a place on the 503A list or interim Category 1, and a 503B facility needs the 503B list or a shortage. For BPC-157, TB-500 and the other peptides that dominate online sales, none of those applies on September 30, 2026, whatever the July vote suggested.

A vial labelled "research use only" is outside all of this. It is not approved, it is not compounded, and it sits in no category; our guide to what that label means explains why FDA and prosecutors treat it as an unapproved drug. For the country-by-country picture, see our legality guide. Statuses here will change: FDA can act on the July recommendations, the February 2027 meeting will take up five more peptides, and GHK-Cu has its own review coming. We date every status on this page for that reason.

Frequently asked questions

Is BPC-157 legal to compound after the July 2026 vote?

Not yet. The advisory committee recommended adding it to the 503A bulks list, but that is advice. As of September 30, 2026, FDA had not added it to the list in 21 CFR 216.23 or placed it in interim Category 1, so no lawful 503A compounding route exists.

What is the difference between 503A and 503B?

A 503A pharmacy compounds for individual patients on prescription and is overseen mainly by state boards. A 503B outsourcing facility follows current good manufacturing practice, is inspected by FDA, and can supply clinics without a named-patient prescription. Neither produces approved drugs.

Which peptides are FDA-approved?

Several, including semaglutide, tirzepatide, tesamorelin (EGRIFTA), bremelanotide (Vyleesi, sold as PT-141 in the grey market) and elamipretide (Forzinity, the SS-31 of forums). BPC-157, TB-500, KPV, MOTS-c, semax and epitalon are not.

What does Category 2 mean?

It is FDA's interim label for a nominated compounding ingredient that raises significant safety concerns, which puts it outside the policy that lets pharmacies use Category 1 substances. As of FDA's May 14, 2026 document it holds six substances, including kisspeptin-10 and ibutamoren (MK-677).

Does removal from Category 2 mean a peptide is safe or approved?

No. The twelve peptides removed in April 2026 left because their nominations were withdrawn, not because FDA found them safe. They were not moved to Category 1, and none is approved.

Related on Grey Peptides

• PCAC July 2026 hub
• Are peptides legal? Country guide
• What "research use only" means
• Regulatory tracker

Sources

1. U.S. Food and Drug Administration. Drugs@FDA (openFDA): VYLEESI (AUTOINJECTOR) (bremelanotide) NDA210557, approved June 21, 2019; EGRIFTA (tesamorelin) BLA022505, approved November 10, 2010; FORZINITY (elamipretide) NDA215244, approved September 19, 2025. Read September 30, 2026.
2. U.S. Food and Drug Administration. Human Drug Compounding (content current as of June 15, 2026). Read September 30, 2026. FDA
3. U.S. Food and Drug Administration. Human Drug Compounding Laws: sections 503A and 503B of the FD&C Act (content current as of December 17, 2024). Read September 30, 2026. FDA
4. U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act (content current as of May 14, 2026). Read September 30, 2026. FDA
5. Code of Federal Regulations. 21 CFR 216.23: bulk drug substances that can be used to compound drug products under section 503A (six listed; four not to be included; the four evaluation criteria). eCFR, current as of September 1, 2026; read September 30, 2026.
6. U.S. Food and Drug Administration. Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the Federal Food, Drug, and Cosmetic Act: guidance for industry (January 2025). FDA
7. U.S. Food and Drug Administration. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the FD&C Act: Categories 1, 2 and 3 (updated May 14, 2026). Read September 30, 2026. FDA
8. U.S. Food and Drug Administration. List of Bulk Drug Substances for Which There Is a Clinical Need Under Section 503B of the FD&C Act (semaglutide, tirzepatide, liraglutide). Federal Register notice, May 1, 2026 (2026-08552). Federal Register
9. U.S. Food and Drug Administration. List of Bulk Drug Substances for Which There Is a Clinical Need Under Section 503B: extension of the comment period to July 30, 2026. Federal Register, June 26, 2026 (2026-12937). Federal Register
10. Orrick, Herrington & Sutcliffe. FDA announces removal of 12 peptides from Category 2 and schedules PCAC meetings to consider adding peptides to 503A bulk drug substances list. April 2026. Read September 30, 2026.
11. U.S. Food and Drug Administration. Pharmacy Compounding Advisory Committee; notice of meeting (July 23-24, 2026); bulk drug substances nominated for inclusion on the section 503A list. Federal Register, April 16, 2026 (2026-07361). Federal Register
12. U.S. Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee (agenda, questions, briefing documents and FDA presentations; content current as of August 6, 2026; no minutes posted when read September 30, 2026). FDA
13. McDermott Will & Schulte. Bulk-list bound? PCAC backs majority of peptides in two-day public meeting (vote tallies for the July 23-24, 2026 meeting). July 2026. Read September 30, 2026.

This guide explains US regulatory terms as of September 30, 2026. It is general information, not legal or medical advice; statuses can change when FDA acts.