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TB-500 reference material, supplied as a lyophilized powder in a sealed vial for in-vitro laboratory research and analytical method development. Each fill size is a separate SKU. Lot and COA records are shown when assigned.
This listing is a research chemical / reference material. No therapeutic, preventive, or diagnostic claims are made or implied. The storefront displays only approved analytical characterization data released through its public report records.
TB-500 is a synthetic variant of thymosin beta-4 of 43 amino acids. Based on Thymosin Beta-4, an endogenous 43-amino-acid peptide encoded by the TMSB4X gene on the X chromosome.
Reported to promote cell migration, cytoskeletal dynamics, and localised tissue remodelling. Vectra makes no claim as to mechanism or effect.
Developed by RegeneRx Biopharmaceuticals. Two Phase 3 ophthalmic trials are on record: SEER-1 returned a positive result in neurotrophic keratopathy, and SEER-3 failed its primary endpoint. First described by RegeneRx Biopharmaceuticals.
Studied in ophthalmic surface repair, cardiac and wound-healing models, and cytoskeletal dynamics. Vectra supplies it as a reference material for in-vitro laboratory research and analytical method development only.
Rated 4 of 5 for ophthalmic indications, 2–3 of 5 for cardiac and wound applications, and 0 of 5 for unregulated subcutaneous use. The evidence is strongly indication-dependent. Ophthalmic use carries Phase 3 data; the unregulated subcutaneous route that dominates the gray market carries none. A rating earned in one route does not transfer to another.
Reported in high-dose intravenous trials at up to 1,260 mg: headache in about 15% of subjects, injection-site reactions in about 10%, and fatigue in about 8%.
Lyophilised: stable at -20°C for two to three years, or at 2–8°C for three to six months. In solution: stable refrigerated for up to 30 days.
Our sources carry no CAS number, molecular formula, or letter sequence for TB-500.
Not approved as a medicinal product. No therapeutic, preventive, or diagnostic claims are made or implied.
Not approved as a medicinal product in any jurisdiction. Current FDA position: 503A Category 2. Awaiting FDA determination and rulemaking following the July 2026 advisory recommendation. Vectra supplies this material as a research-use-only reference material. No therapeutic, preventive, or diagnostic claims are made or implied.
Yes. The FDA Pharmacy Compounding Advisory Committee considered it at its July 23–24, 2026 meeting. The committee's vote was: recommended (8–6, 1 abstention, July 23). The votes are advisory and not binding. FDA makes the final determination, and inclusion requires proposed and final rulemaking, with formal approval by the Secretary of Health and Human Services. None of the six is legal to compound on the strength of the vote alone; reporting at the time put the earliest realistic timeline at roughly twelve months.
FDA reviewers concluded the substance did not meet the agency's four-part standard, citing short and underpowered studies. FDA career reviewers published briefing documents recommending against all seven substances, concluding that none met the agency's four-part evidentiary standard.
Category 2 is not a ban and not a scheduling action. It describes where a nominated substance sits in an unfinished evaluation process. An interim FDA designation for nominated bulk drug substances for which the agency identified potential significant safety risks. Substances in Category 2 sit outside FDA's Category 1 enforcement-discretion policy.
These are the specific, documented failure modes that lot-level third-party analysis addresses. A report reachable from the lot code printed on the vial — without asking the seller for it — is the only document that answers 'is this vial what the label says'. That is why every Vectra vial carries a QR code resolving to its own lot's published report.
Findings reported by commercial testing providers. Each names its source; none is registry- or peer-review-grade, so read them as a documented pattern rather than established prevalence.
Yes, and altered certificates have been reported in this market at material rates — see the testing findings above. Three properties make a report hard to fake:
Peptide identity data in the vendor market is often wrong in ways that are hard to see. Near-identical compounds get their CAS numbers, residue ranges, formulas and molecular weights swapped. A certificate can be internally consistent and still describe a different molecule than the label names. Most commercial peptide material ships as an acetate salt, not free base. The two forms have different measured masses, so a figure quoted against the wrong one will not reconcile. A report that does not state which form it assayed cannot be checked at all.
The standard our own reports are built to meet:
FDA has acted in this market between 2024 and 2026. Actions include a civil forfeiture over $1.7 million against a compounding operation, several rounds of warning letters to peptide vendors, and more than thirty letters in March 2026 concerning compounded GLP-1 products.
Buyers here increasingly compare document trail, not price.