TB-500 regulatory status: Category 2 and the path forward

FDA removed TB-500 from Category 2 in April 2026. FDA has not yet decided whether to add it to the 503A bulks list.

TL;DR

• FDA placed TB-500 in Category 2 on September 29, 2023. FDA removed it from Category 2 on April 22, 2026, after its nomination was withdrawn.
• 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. In July 2026, FDA's Pharmacy Compounding Advisory Committee voted 8 yes, 6 no, and 1 abstention to recommend adding TB-500 to the Section 503A bulk drug substances list. As of September 2026, FDA has not made a final decision.
• 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 it is

The FDA evaluates bulk drug substances that compounding pharmacies may use. FDA placed TB-500 in Category 2 on September 29, 2023. FDA's Category 2 list is for bulk drug substances that FDA says raise significant safety risks. FDA removed TB-500 from Category 2 on April 22, 2026, after its nomination was withdrawn. As of September 14, 2026, TB-500 is not in any FDA 503A category and is not on the 503A bulks list.

How it works procedurally

The procedural pathway for adding a peptide to the Section 503A bulk drug substances list is the same as for any bulk drug substance: PCAC review and recommendation, FDA proposed rule or guidance published in the Federal Register, public comment period (typically 30–60 days), final FDA rule, and only then does the change become legally effective. FDA's interim categories work differently: FDA removed TB-500 from Category 2 in April 2026 after its nomination was withdrawn.

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. The next milestone was the July 23–24, 2026 PCAC meeting, where the committee voted 8 yes, 6 no, and 1 abstention to recommend adding TB-500 to the Section 503A bulk drug substances list. The committee is advisory. As of September 2026, FDA has not made a final decision, and formal addition to the list requires further FDA action.

Who asks about it

People come to this topic when they have read news coverage suggesting TB-500 is "back" or "approved again" and want to know whether that is accurate as of today. The accurate answer, as of September 2026, is that FDA's advisory committee has recommended TB-500 for the 503A bulks list, but FDA has not yet made a final decision.

What to know before considering it

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. Vendors marketing TB-500 for human use through online or research-chemical channels without a valid prescription are not operating within the licensed clinical framework. Halftime Health will update this post when FDA makes a final decision.

The Halftime POV

The TB-500 reclassification process matters and is worth following. The distance between "recommended" and "decided" is also real. Both can be described accurately at once, and that is the position we take in our content.

Related reading:

• Category 1 vs Category 2 peptides: the access framework
• Secretary Kennedy's February 2026 peptide remarks
• BPC-157 and the FDA: Category 2 status and what comes next

FAQ

Q: Is TB-500 legal in the United States? A: TB-500 was placed in FDA Category 2 in 2023. FDA removed TB-500 from Category 2 on April 22, 2026, after its nomination was withdrawn. As of September 14, 2026, TB-500 is not in any FDA 503A category and is not on the 503A bulks list. FDA has not made a final decision on TB-500. At its July 23–24, 2026 meeting, FDA's Pharmacy Compounding Advisory Committee voted 8 yes, 6 no, and 1 abstention to recommend adding TB-500 to the Section 503A bulk drug substances list. The committee is advisory, and formal addition to the list requires further FDA action. 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 difference between 503A and 503B compounding? A: 503A pharmacies prepare individualized prescriptions on demand for a specific patient under physician supervision. 503B facilities are outsourcing facilities that manufacture larger batches without patient-specific prescriptions. Halftime Health works with 503A pharmacies only — every prescription is prepared for the individual patient.

Q: Did Secretary Kennedy's February 2026 remarks change TB-500 status? A: 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. The remarks did not change TB-500's status. FDA removed TB-500 from Category 2 on April 22, 2026, after its nomination was withdrawn. As of September 14, 2026, TB-500 is not in any FDA 503A category and is not on the 503A bulks list. FDA has not made a final decision on TB-500. At its July 23–24, 2026 meeting, FDA's Pharmacy Compounding Advisory Committee voted 8 yes, 6 no, and 1 abstention to recommend adding TB-500 to the Section 503A bulk drug substances list. The committee is advisory, and formal addition to the list requires further FDA action.

Disclaimer

As of September 2026, FDA has not made a final decision on TB-500. At its July 23–24, 2026 meeting, FDA's Pharmacy Compounding Advisory Committee voted 8 yes, 6 no, and 1 abstention to recommend adding TB-500 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 only and is not medical advice. Halftime Health only prescribes through licensed physicians in states where our partner physicians are credentialed.

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Sources

• FDA. "Bulk Drug Substances That May Be Used in Compounding Under Section 503A of the Federal Food, Drug, and Cosmetic Act." FDA.gov
• FDA. PCAC Meeting Materials, 2023. FDA.gov
• FDA. "July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee." FDA.gov
• McDermott Will & Schulte. "Bulk-list bound? PCAC backs majority of peptides in two-day public meeting." 2026
• Robert F. Kennedy Jr., HHS Secretary. Remarks on peptides, The Joe Rogan Experience podcast, February 27, 2026. HHS issued no press release or Federal Register notice.

This article discusses compounds whose FDA compounding status has been under review (see our FDA categorization explainer). 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. This article is provided for educational purposes only and does not constitute medical advice or an offer to sell.