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503A Compounding of Peptides: How the Rules Work
How 503A and 503B compounding differ, what FDA's lists and categories mean, and what HHS's Oct. 2026 interim policy on six peptides does and does not do.
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“503A” shows up in almost every story about compounded peptides. This guide explains what it is, how it differs from 503B, how FDA’s lists and categories work, and what HHS’s October 2026 policy changed and did not change.
The short answer
HHS’s October 2026 policy is an interim enforcement-discretion policy for six peptides under 503A, under conditions. It is not FDA approval and does not add them to the 503A bulks list.
Section 503A is the part of federal law that sets conditions for pharmacies and physicians who compound drugs for individual patients. It does not approve any compounded product. FDA says compounded drugs are not FDA-approved, and that it does not review them for safety, effectiveness or quality before they are marketed. This guide gives no legal conclusion about any product. For a specific situation, ask a licensed attorney, clinician or pharmacist.
How this guide is built
This is a regulatory explainer, not a ranking. We use FDA’s and HHS’s own words and say when a source is a law firm’s analysis (a secondary source, not a legal finding). We checked the status on Nov. 5, 2026, and some of it will change; see “What could change soon.” We do not cover where to buy, how to import or how to use any peptide. For the wider picture, see are peptides legal in the US.
What are 503A and 503B?
A compounded drug is made when a licensed pharmacist or physician, or a person supervised by a licensed pharmacist at an outsourcing facility, combines, mixes or alters ingredients. FDA describes two sets of rules (FDA):
| Section 503A | Section 503B | |
|---|---|---|
| What it sets | The conditions under which compounded products are exempt from FDA approval before marketing, from current good manufacturing practice (CGMP) requirements and from labeling with adequate directions for use | A voluntary category of compounders called outsourcing facilities |
| Who it covers | Licensed pharmacists and physicians | Outsourcing facilities, supervised by a licensed pharmacist |
| CGMP | Exempt, if the conditions are met | Subject to CGMP requirements |
| Prescription | One condition is a valid patient-specific prescription | May distribute under a patient-specific prescription or in response to an order from a health care provider |
| Compounded product approved by FDA? | No | No |
For drugs that already have an approved version, FDA adds a limit: a compounder may not make products that are “essentially copies” of a commercially available drug regularly or in inordinate amounts. See what FDA says about compounded GLP-1 drugs.
What are the lists and categories?
FDA keeps lists of bulk drug substances, which FDA says are also known as active pharmaceutical ingredients. The ones that matter for peptides:
- The 503A bulks list and FDA’s categories. The 503A bulks list is the list of bulk drug substances that can be used under 503A when there is no applicable USP or NF monograph and the substance is not a component of an FDA-approved drug. Separately, FDA keeps a list of nominated substances in three categories, updated May 14, 2026; Category 1 holds substances under evaluation.
- 503B. FDA keeps a separate list of substances nominated under 503B, also in categories.
- Category 2. FDA’s page on substances that may present significant safety risks lists substances FDA said may present significant safety risks for compounding.
- The advisory committee. FDA’s Pharmacy Compounding Advisory Committee (PCAC) reviews substances and votes on them. Its votes are cited below.
Where do individual peptides sit?
As of Nov. 5, 2026. We checked the documents linked and draw no legal conclusion about any product.
| Group | Peptides | What the documents say |
|---|---|---|
| Six peptides in HHS’s interim policy | BPC-157, TB-500, epitalon, semax (free base), KPV, MOTS-c | HHS says it does not intend to take enforcement action against certain 503A compounding, under conditions. See below |
| Listed by FDA as withdrawn from Category 2 | The six above, plus LL-37, CJC-1295, AOD-9604, selank and thymosin alpha-1 | FDA’s page, updated April 22, 2026, lists their nominations as withdrawn; HHS says its six were in Category 2 until that date. None appears in FDA’s 503A categories list (FDA; categories) |
| Still in Category 2 | Kisspeptin-10 (503A), ipamorelin (503B) | FDA’s page lists them |
| Advisory committee voted against listing (2024) | Ipamorelin, CJC-1295, AOD-9604, thymosin alpha-1 | See the Oct. 29, 2024 and Dec. 4, 2024 minutes |
| Category 1 (under evaluation) | GHK-Cu, non-injectable forms | FDA says it intends to consult its advisory committee before the end of February 2027 (FDA list) |
| Approved drugs with a 503B proposal | Semaglutide, tirzepatide, liraglutide | On May 1, 2026, FDA proposed not including them on the 503B list. We found no final notice |
| Cannot be compounded, per FDA | Retatrutide, cagrilintide | FDA says they “cannot be used in compounding under federal law” (FDA, Oct. 1, 2026) |
Leaving Category 2 did not make a substance compoundable. HHS says that neither the placement nor the removal changed their status under section 503A.
What did HHS do on Oct. 30, 2026?
HHS’s October 2026 policy is an interim enforcement-discretion policy for six peptides under 503A, under conditions. It is not FDA approval and does not add them to the 503A bulks list.
HHS said it does not intend to take enforcement action against state-licensed pharmacies, federal facilities and licensed physicians that compound the six peptides under section 503A, if all of the policy’s conditions are met. The covered forms and routes, per the policy:
| Peptide | Form covered | Routes covered |
|---|---|---|
| BPC-157 | acetate | subcutaneous, intramuscular, oral, topical |
| TB-500 | acetate | subcutaneous, intramuscular |
| Epitalon | acetate | subcutaneous, intramuscular, in intermittent courses |
| Semax | free base | intranasal |
| KPV | acetate | topical, oral |
| MOTS-c | acetate | subcutaneous, intramuscular |
Not FDA-approved. Under an interim policy published Oct. 30, 2026, and open for public comment, HHS said it does not intend to take enforcement action against state-licensed pharmacies, federal facilities or licensed physicians that compound BPC-157, TB-500, epitalon, semax, KPV or MOTS-c under section 503A, as long as all of the policy’s conditions are met, including limits on form and route. This is enforcement discretion, not approval. FDA does not review compounded drugs for safety, effectiveness or quality before they are marketed. HHS may revisit the policy. Read the notice.
What are the conditions?
In summary, per the policy:
- Exact identification of the substance, with a certificate of analysis and testing on each batch.
- An original manufacturer registered with FDA and following CGMP.
- Reporting of products, serious adverse events and quality problems to FDA’s MedWatch program and to the states.
- A label stating “This is a compounded drug product. Not for resale.”
- A single active ingredient.
- For oral products, documentation of oral bioavailability in humans.
- For injection, a syringe cleared as a medical device.
- A patient-specific prescription, and compliance with the rest of the law.
What does the policy not do?
- It is not FDA approval. HHS notes that FDA does not review compounded drugs.
- It is interim and open to comment. Public comments on the policy are open until Nov. 13, 2026, at 11:59 p.m. Eastern (docket).
- It creates no rights. The notice says it “does not establish any rights for any person and is not binding on HHS or the public.” HHS may revisit it.
- It does not add any peptide to FDA’s lists. It applies until a final rule includes or excludes the substances.
- It does not cover outsourcing facilities (503B) or blends, according to a law-firm analysis (secondary source); the single-ingredient condition is in HHS’s text.
- It does not replace state law, per the same analysis.
- It does not cover semaglutide, tirzepatide or other approved drugs. It names six peptides, and none of them is semaglutide or tirzepatide.
Do FDA and HHS agree?
Not entirely, and we do not choose between them. In July 2026, FDA’s drug center proposed not listing any of seven peptides it reviewed, and an advisory committee voted in favor of listing most of them, according to a law-firm account (secondary source). HHS’s policy relies on batch certificates and historical use that it describes as “documented and quantified,” and the document we read does not publish those data. The Federal Register notice announces it as a “draft” open for comment, while the document itself calls it an interim policy. Where it matters for a claim, we say which source we are using.
How did we get here?
| Date | What happened | Source |
|---|---|---|
| September 2023 | FDA placed these peptides in Category 2 | HHS policy |
| Oct. and Dec. 2024 | The advisory committee voted against ipamorelin, CJC-1295, AOD-9604 and thymosin alpha-1 | Oct. 29, Dec. 4 |
| April 22, 2026 | FDA updated its Category 2 page; HHS says its six peptides left Category 2 that day after nominations were withdrawn | FDA; HHS |
| May 1, 2026 | FDA proposed not including semaglutide, tirzepatide or liraglutide on the 503B list | Federal Register |
| May 14, 2026 | FDA updated its list of substances nominated under 503A | FDA list |
| July 23–24, 2026 | FDA’s drug center proposed not listing seven peptides; the advisory committee met | FDA |
| Oct. 30, 2026 | HHS published the interim policy | Federal Register |
What could change soon?
- The comment period. Public comments on the policy are open until Nov. 13, 2026, at 11:59 p.m. Eastern. After it closes, the policy remains interim. A law-firm analysis estimates a final rule could take 12 to 24 months (secondary source).
- FDA’s decision on the 503B list for GLP-1 drugs. FDA extended comments on its proposal to July 30, 2026 (Federal Register). We found no final notice as of Nov. 5, 2026.
- The advisory committee on GHK-Cu, which FDA says it intends to consult before the end of February 2027.
- State boards may update their notices.
How do state rules fit?
State rules are separate. Before the policy was issued, boards in Alabama and Mississippi told licensees they may not compound, administer or dispense non-FDA-approved or research-grade peptides. We found no update from them as of Nov. 5, and it isn’t clear how those notices apply to compounding under the HHS policy. We did not review other states.
What do the policy’s conditions mean for a patient?
They are a list of questions you can ask, not a way to decide whether a product is lawful:
- Is this prescribed for me by name, as the policy requires?
- Is it one active ingredient, or a blend? The policy covers a single ingredient.
- Which form and route is it? Each peptide is covered only in the forms and routes above.
- Does the label say “This is a compounded drug product. Not for resale.”?
- Who made the starting substance, and is that manufacturer registered with FDA?
- Is the pharmacy or physician licensed in my state, and does my state board have a notice?
A “research use only” product sold online is a different channel. See what “research use only” means.
Which claims are not supported?
- “HHS legalized these peptides” or “they are FDA-approved.” The policy is interim enforcement discretion under conditions. It is not approval.
- “They are now on the 503A list.” The policy does not add them.
- “It covers any form or route.” It covers specific forms and routes, and a single active ingredient.
- “It covers blends or outsourcing facilities.” A law-firm analysis says it does not, and the single-ingredient condition is in the policy text.
- “It covers semaglutide or tirzepatide.” It does not.
- “Leaving Category 2 made them compoundable.” HHS says the removal did not change their status under section 503A.
Frequently asked questions
What is the difference between 503A and 503B?
Section 503A sets conditions for compounding by licensed pharmacists and physicians, with a valid patient-specific prescription as one condition. Section 503B is a voluntary category of outsourcing facilities subject to CGMP requirements.
Did FDA approve BPC-157 or other peptides in October 2026?
No. HHS published an interim policy saying it does not intend to take enforcement action against certain compounding of six peptides under conditions. That is not approval. See our BPC-157 guide and semax guide.
Does the HHS policy cover compounded semaglutide or tirzepatide?
No. Those are approved drugs, and they are not among the six peptides the policy names. See what FDA says about compounded GLP-1 drugs.
When does the comment period end?
Public comments on the policy are open until Nov. 13, 2026, at 11:59 p.m. Eastern.
Is compounded BPC-157 legal?
We do not give legal conclusions. HHS says it does not intend to take enforcement action against certain 503A compounding of BPC-157 under conditions, on an interim basis. State rules are separate.
From Best Peptides Today
Sources we checked
- Federal Register: HHS enforcement discretion policy on 503A peptide compounding (Oct. 30, 2026)Other. Accessed .
- HHS: Enforcement Discretion Policy, with Appendices A and BOther. Accessed .
- Regulations.gov docket HHS-OASH-2026-0496Other. Accessed .
- FDA: compounding laws and policiesFDA. Accessed .
- FDA: bulk drug substances used in compoundingFDA. Accessed .
- FDA: bulk drug substances that may present significant safety risks (Category 2)FDA. Accessed .
- FDA: bulk drug substances nominated under section 503A, by category (updated May 14, 2026)FDA. Accessed .
- FDA: bulk drug substances nominated under section 503B, by category (updated March 21, 2025)FDA. Accessed .
- FDA CDER proposal on seven peptides (July 2026)FDA. Accessed .
- FDA Pharmacy Compounding Advisory Committee minutes (Oct. 29, 2024)FDA. Accessed .
- FDA Pharmacy Compounding Advisory Committee minutes (Dec. 4, 2024)FDA. Accessed .
- McDermott+: PCAC votes on peptides (secondary source)Other. Accessed .
- Federal Register: proposed 503B bulk drug substances list (May 1, 2026)Other. Accessed .
- Federal Register: extension of comments on the 503B list (June 26, 2026)Other. Accessed .
- FDA clarifies policies for compounders as national GLP-1 supply stabilizesFDA. Accessed .
- FDA: FDA's concerns with unapproved GLP-1 drugs used for weight lossFDA. Accessed .
- FDA: notice to compounders on changes that affect compounding (March 23, 2020)FDA. Accessed .
- Frier Levitt: HHS peptide compounding enforcement discretion policy (secondary source)Other. Accessed .
- Alabama Board of Medical Examiners: notice on prescribing non-FDA-approved research-grade peptidesOther. Accessed .
- Mississippi nursing, pharmacy and medical licensure boards: joint statement on peptides (Aug. 19, 2026)Other. Accessed .
Written and maintained by the Best Peptides For Editorial Team. How we rate evidence.