Category 2 peptides: what the access limits mean for patients
The FDA's Category 2 designation is not a permanent ban — but FDA says the substances in it raise significant safety risks.
TL;DR
- FDA removed MOTS-c, BPC-157, and TB-500 from Category 2 on April 22, 2026. FDA's advisory committee voted in July 2026 to recommend adding all three to the Section 503A bulk drug substances list, and FDA's final decision is pending.
- Limited legal access pushes some patients toward unregulated gray-market sources, which carry real risks.
- In February 2026, HHS Secretary Robert F. Kennedy Jr. said in a podcast interview that FDA would soon make more peptides accessible. That was not a formal proposal; the formal step was FDA's April 2026 change to its category list.
What it is
The FDA reviews bulk drug substances — the raw ingredients compounding pharmacies use. It places each one into a category. Category 1 lists substances FDA is still evaluating. Category 2 lists substances FDA says raise significant safety risks. Section 503A is the law governing most retail compounding pharmacies. FDA's policy of not taking action against compounding with a substance not yet on the 503A bulks list applies only to Category 1 substances, when other conditions are met (FDA interim policy, January 2025).
Peptides that FDA placed in Category 2 in 2023 include TB-500 (thymosin beta-4 synthetic), MOTS-c (mitochondrial open reading frame of the twelve S rRNA-c), and BPC-157 (body protection compound). FDA removed all three from Category 2 on April 22, 2026, after their nominations were withdrawn. As of September 14, 2026, none of them is in any FDA 503A category or on the 503A bulks list. As of September 2026, FDA has not made a final decision on BPC-157 or TB-500. At its July 23–24, 2026 meeting, FDA's Pharmacy Compounding Advisory Committee voted separately on each. Both votes were 8 yes, 6 no, and 1 abstention to recommend adding the peptide to the Section 503A bulk drug substances list. The committee is advisory, and formal addition to the list requires further FDA action. On July 23, 2026, the committee also voted to recommend adding MOTS-c to the list.
How it works
Imagine a licensed kitchen that can only use ingredients from an approved supplier list. If an ingredient is not on the list, the kitchen cannot legally use it. Demand doesn't change that. Promising early research doesn't either. Category 2 is that "not on the list" status.
The ingredient may still be studied in research settings. It may eventually be reclassified. But today, a licensed 503A pharmacy cannot fill a prescription for it.
Who asks about it
People come here after reading about TB-500, MOTS-c, or other peptides that were in Category 2 — in research articles, from a physician, or in health communities. They want to know what Category 2 means. And they want to know what their legal options actually are.
What the research says
The evidence base for Category 2 peptides is mostly preclinical. That means studies in animals or cell cultures, not human clinical trials. The FDA's category determination reflects that gap. Federal Register notices document the agency's review of available literature and its reasoning (Federal Register, 2021; FDA, 2024). In February 2026, HHS Secretary Robert F. Kennedy Jr. said in a podcast interview that FDA would soon make more peptides accessible. That was not a formal proposal; the formal step was FDA's April 2026 change to its category list. FDA removed BPC-157, TB-500, and MOTS-c from Category 2 on April 22, 2026.
What to know before considering it
Patients who cannot access Category 2 peptides through licensed channels sometimes turn to vendors selling products labeled "research use only." These are not made under the sterile compounding standards required of licensed pharmacies. Potency, purity, and sterility are unverified. Any peptide access requires a licensed physician. If a peptide you want is in Category 2, your healthcare provider can advise on legal options and track regulatory changes as they happen.
The Halftime POV
At Halftime Health, we follow peptide regulatory status closely because it changes. Our patients deserve accurate information about what is and is not legally available. Halftime Health protocols are prescribed by licensed physicians and prepared by licensed 503A compounding pharmacies. Compounded drugs are not FDA-approved and have not been evaluated by FDA for safety or effectiveness. Of the peptides FDA added to Category 2 in 2023, only MK-677 (ibutamoren) and kisspeptin-10 remain there as of September 14, 2026. We will update our protocols as the FDA Federal Register reflects any formal reclassification.
Related reading:
- Why certain peptides are still in Category 2
- Secretary Kennedy's February 2026 peptide remarks
- 12 peptides removed from FDA restriction in 2026
- The three-category access model explained
- FDA reclassification April 2026 explained
FAQ
Q: What does FDA Category 2 mean for a peptide? A: Category 2 is FDA's interim list of bulk drug substances nominated for compounding under Section 503A that FDA says raise significant safety risks. FDA's policy of not taking action against compounding with a substance not yet on the 503A bulks list applies only to Category 1 substances, when other conditions are met. As of September 14, 2026, Category 2 lists six substances, including the peptides ibutamoren (MK-677) and kisspeptin-10.
Q: Are BPC-157, TB-500, and MOTS-c currently available from compounding pharmacies? A: FDA removed BPC-157, TB-500, and MOTS-c from Category 2 on April 22, 2026, after their nominations were withdrawn. As of September 14, 2026, none of them is in any FDA 503A category or on the 503A bulks list. In February 2026, HHS Secretary Robert F. Kennedy Jr. said in a podcast interview that FDA would soon make more peptides accessible. That was not a formal proposal; the formal step was FDA's April 2026 change to its category list. As of September 2026, FDA has not made a final decision on BPC-157 or TB-500. At its July 23–24, 2026 meeting, FDA's Pharmacy Compounding Advisory Committee voted separately on each. Both votes were 8 yes, 6 no, and 1 abstention to recommend adding the peptide to the Section 503A bulk drug substances list. The committee is advisory, and formal addition to the list requires further FDA action. On July 23, 2026, the committee also voted to recommend adding MOTS-c to the list. Halftime Health protocols are prescribed by licensed physicians and prepared by licensed 503A compounding pharmacies. Compounded drugs are not FDA-approved and have not been evaluated by FDA for safety or effectiveness.
Q: What is the patient risk of seeking Category 2 peptides outside licensed pharmacies? A: Unlicensed online vendors may sell peptides labeled "research use only." These products are not manufactured under the sterile compounding standards required of licensed pharmacies, and potency, purity, and sterility are unverified.
Q: What is the difference between Category 1 and Category 2? A: Category 1 lists bulk drug substances that FDA is still evaluating. FDA's policy of not taking action against compounding with a substance not yet on the 503A bulks list applies only to Category 1 substances, when other conditions are met. Category 2 lists substances that FDA says raise significant safety risks. Category 3 lists substances that were nominated without adequate support.
Q: How should patients find out the current regulatory status of a specific peptide? A: The FDA maintains an updated list of 503A bulk drug substance categories at fda.gov. Your prescribing physician can also advise on what is legally accessible through licensed channels at any given time.
Disclaimer
Several peptides discussed in this article — including MOTS-c — were previously in FDA's Category 2. FDA removed them from Category 2 on April 22, 2026. As of September 14, 2026, they are not in any FDA 503A category and are not on the 503A bulks list. As of September 2026, FDA has not made a final decision on BPC-157 or TB-500. At its July 23–24, 2026 meeting, FDA's Pharmacy Compounding Advisory Committee voted separately on each. Both votes were 8 yes, 6 no, and 1 abstention to recommend adding the peptide to the Section 503A bulk drug substances list. The committee is advisory, and formal addition to the list requires further FDA action. This article is educational and is not medical advice. Halftime Health only prescribes through licensed physicians in states where our partner physicians are credentialed.
Get started
We share what we learn along the way — the research, the regulations, the real-world trade-offs. Get started with Halftime Health.
Sources
- U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A. FDA, 2024. https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503a
- Robert F. Kennedy Jr., HHS Secretary. Remarks on peptides, The Joe Rogan Experience podcast. February 27, 2026. No HHS press release or Federal Register notice was issued.
- Federal Register. Bulk Drug Substances That May Be Used in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act. 2021. https://www.federalregister.gov
Frequently asked questions
What does FDA Category 2 mean for a peptide?
Category 2 is FDA's interim list of bulk drug substances nominated for compounding under Section 503A that FDA says raise significant safety risks. FDA's policy of not taking action against compounding with a substance not yet on the 503A bulks list applies only to Category 1 substances, when other conditions are met. As of September 14, 2026, Category 2 lists six substances, including the peptides ibutamoren (MK-677) and kisspeptin-10.
Are BPC-157, TB-500, and MOTS-c currently available from compounding pharmacies?
FDA removed BPC-157, TB-500, and MOTS-c from Category 2 on April 22, 2026, after their nominations were withdrawn. As of September 14, 2026, none of them is in any FDA 503A category or on the 503A bulks list. In February 2026, HHS Secretary Robert F. Kennedy Jr. said in a podcast interview that FDA would soon make more peptides accessible. That was not a formal proposal; the formal step was FDA's April 2026 change to its category list. As of September 2026, FDA has not made a final decision on BPC-157 or TB-500. At its July 23–24, 2026 meeting, FDA's Pharmacy Compounding Advisory Committee voted separately on each. Both votes were 8 yes, 6 no, and 1 abstention to recommend adding the peptide to the Section 503A bulk drug substances list. The committee is advisory, and formal addition to the list requires further FDA action. On July 23, 2026, the committee also voted to recommend adding MOTS-c to the list. Halftime Health protocols are prescribed by licensed physicians and prepared by licensed 503A compounding pharmacies. Compounded drugs are not FDA-approved and have not been evaluated by FDA for safety or effectiveness.
What is the patient risk of seeking Category 2 peptides outside licensed pharmacies?
Unlicensed online vendors may sell peptides labeled 'research use only.' These products are not manufactured under the sterile compounding standards required of licensed pharmacies, and potency, purity, and sterility are unverified.
What is the difference between Category 1 and Category 2?
Category 1 lists bulk drug substances that FDA is still evaluating. FDA's policy of not taking action against compounding with a substance not yet on the 503A bulks list applies only to Category 1 substances, when other conditions are met. Category 2 lists substances that FDA says raise significant safety risks. Category 3 lists substances that were nominated without adequate support.
How should patients find out the current regulatory status of a specific peptide?
The FDA maintains an updated list of 503A bulk drug substance categories at fda.gov. Your prescribing physician can also advise on what is legally accessible through licensed channels at any given time.
Keep reading
Every protocol is reviewed by a licensed physician and filled by a licensed 503A compounding pharmacy.
Membership from $39/mo, or $390 for the year, including your onboarding panel. Each protocol is its own monthly subscription.