Peptide Price Finder

Home · Research · Healing & recovery

TB-500 research

What published studies found for TB-500: 11 papers, 7 in humans, with sample sizes and key results, plus 15 registered clinical trials.

D
Little or no evidence
Why: Only one rat study tests TB-500 itself; the human trials and most animal work used full-length thymosin beta-4, a different molecule.

TB-500 is a synthetic version of a fragment of thymosin beta-4; essentially all published human data are small trials of full-length thymosin beta-4 applied topically (eye drops for dry eye and neurotrophic keratopathy, a gel for venous ulcers), with modest or borderline results. There are no published human trials of injected TB-500 itself; the rest is animal and cell work, mostly on full-length thymosin beta-4, with only one rat study of TB-500 itself.

✓ 5 positive~ 2 mixed? 4 inconclusive

Small topical thymosin beta-4 trials and two phase I intravenous trials of full-length thymosin beta-4 reported only mild to moderate adverse events; there are no published human safety data for injected TB-500.

US compounding: Recommended for compounding, not legal yet. FDA's Pharmacy Compounding Advisory Committee voted on July 23-24, 2026 to recommend adding it to the 503A bulks list (FDA staff had recommended against). The vote isn't binding: compounding stays illegal until FDA accepts it and finishes proposed and final rulemaking, which typically takes a year or more. Vote: 8-6 (evaluated for wound healing). Status for every peptide.

Browse and filter these papersTB-500 prices and vendors

Reported side effects

Registered clinical trials

15 trials of TB-500 on ClinicalTrials.gov: 3 active, 7 completed, 9 with posted results. Registered trials include ones that haven't published yet.

TrialStatusPhasePeopleSponsor
Recombinant Human Thymosin Beta 4 for Injection(NL005) for Acute Myocardial InfarctionNCT07586865 · started 2026-05-18Not yet recruitingPhase 2189Beijing Northland Biotech. Co., Ltd.
TB-500 (Thymosin Beta 4 17-23 Fragment) for Cardiovascular Biomarkers in Stable ASCVDNCT07487363 · started 2026-02-05RecruitingPhase 1, Phase 280Hudson Biotech
Assessment of the Safety and Efficacy of 0.1% RGN-259 Ophthalmic Solution for the Treatment of NK: SEER-2NCT05555589 · started 2023-04-11RecruitingPhase 370ReGenTree, LLC
Assessment of the Safety and Efficacy of RGN-259 Ophthalmic Solutions for Dry Eye Syndrome: ARISE-3NCT03937882 · started 2019-05-24 · results postedCompletedPhase 3700ReGenTree, LLC
Assessment of the Safety and Efficacy of RGN-259 Ophthalmic Solutions for Dry Eye Syndrome : ARISE-2NCT02974907 · started 2016-11 · results postedCompletedPhase 3601ReGenTree, LLC
Safety and Efficacy of Thymosin Beta 4 Ophthalmic Solution in Patients With Dry EyeNCT01387347 · started 2011-08 · results postedCompletedPhase 272ReGenTree, LLC
Study of Thymosin Beta 4 in Patients With Venous Stasis UlcersNCT00832091 · started 2006-07 · results postedCompletedPhase 272RegeneRx Biopharmaceuticals, Inc.
Study of Thymosin Beta 4 in Patients With Pressure UlcersNCT00382174 · started 2006-05 · results postedCompletedPhase 272RegeneRx Biopharmaceuticals, Inc.
A Phase 2 Study on Effect of Thymosin Beta 4 on Wound Healing in Patients With Epidermolysis BullosaNCT00311766 · started 2006-02 · results postedTerminatedPhase 230RegeneRx Biopharmaceuticals, Inc.
Assessment of the Safety and Efficacy Study of RGN-259 Ophthalmic Solutions for Neurotrophic Keratopathy : SEER-1NCT02600429 · started 2015-09-17 · results postedTerminatedPhase 318ReGenTree, LLC
A Phase 2 Study of the Safety and Efficacy of Thymosin Beta 4 for Treating Corneal WoundsNCT00598871 · started 2007-12 · results postedTerminatedPhase 212ReGenTree, LLC
Comparative Study of Thymosin Beta 4 Eye Drops vs. Vehicle in the Treatment of Severe Dry EyeNCT01393132 · started 2011-03 · results postedCompletedPhase 29Michigan Cornea Consultants, PC

All 15 TB-500 trials, with countries and recruiting status

Human studies

~ Mixedhuman RCTCardiovasc Res · 2025

Recombinant human thymosin beta 4 improves ischemic cardiac dysfunction in mice and patients with acute ST-segment elevation myocardial infarction after reperfusion.

n = 96 humans and animalsMouse and in vitro studies plus a randomized, placebo-controlled, double-blind human trial90-day follow-up in patients

Recombinant human thymosin beta-4 prevented cardiac dysfunction in mice after ischemia-reperfusion, but in a 96-patient STEMI trial the overall infarct-area difference vs placebo was not significant, though infarct area was smaller in the 43 patients dosed within 8 h (full-length protein, not TB-500).

Key resultInfarct area was significantly smaller with rhTB4 in the early-dosed group (n = 43) at 90 days, but overall differences in infarct area were not significant (n = 96)
Studied
Mice with myocardial ischemia/reperfusion and patients with acute ST-segment elevation myocardial infarction after reperfusion
Compared with
Placebo
Main outcome
Cardiac function and infarct area
Sample
96 STEMI patients; 43 received the first dose within 8 h of PCI; mouse and cell experiments also reported
Authors' conclusion
The authors say rhTB4 mitigates cardiac dysfunction in an ErbB2-dependent manner in mice and call for further rigorous randomized studies on early use after reperfusion.
Limitations
Overall human result was not significant; the early-dosing benefit comes from a subgroup; full-length protein, not TB-500.
PubMed 41229390DOI
? Inconclusivehuman RCTAnn N Y Acad Sci · 2010

The effect of thymosin treatment of venous ulcers.

n = 73 humansDouble-blind, placebo-controlled, dose-escalation phase 2 study of topical thymosin β4

Phase 2 dose-escalation trial of topical thymosin beta-4 in 73 patients with venous leg ulcers: safety comparable to placebo; authors report only that the 0.03% dose 'may have the potential' to speed healing.

Key resultComplete wound healing was achieved within 3 months in about 25% of patients at the 0.03% dose (no p-value in the abstract).
Studied
Patients with venous stasis ulcers
Compared with
Placebo
Main outcome
Safety, tolerability and wound healing
Sample
73 patients randomized at 8 European sites
Authors' conclusion
Safety was acceptable and comparable to placebo. A 0.03% dose may have potential to accelerate healing, especially in small to moderate wounds.
Limitations
Phase 2 dose-escalation study; efficacy findings are suggestive only.
PubMed 20536470DOI
~ Mixedhuman RCTInt J Mol Sci · 2022

0.1% RGN-259 (Thymosin ß4) Ophthalmic Solution Promotes Healing and Improves Comfort in Neurotrophic Keratopathy Patients in a Randomized, Placebo-Controlled, Double-Masked Phase III Clinical Trial.

10 RGN-259 and 8 placebo subjectsRandomized, placebo-controlled, double-masked phase III trial of 0.1% RGN-259 (thymosin β4) eye drops4 weeks of treatment; assessed to day 43

Phase III trial in 18 patients with neurotrophic keratopathy: thymosin beta-4 eye drops healed the corneal defect in 6 of 10 vs 1 of 8 on placebo at 4 weeks (p=0.066, not significant on the main endpoint), with significant differences at some later time points and comfort measures.

Key resultComplete healing at 4 weeks in 6 of 10 RGN-259 subjects vs 1 of 8 placebo subjects (p = 0.0656), a trend that did not reach significance.
Studied
Patients with Stage 2 or 3 neurotrophic keratopathy and persistent epithelial defects
Compared with
Placebo
Main outcome
Complete healing of the epithelial defect at 4 weeks
Authors' conclusion
The authors concluded 0.1% RGN-259 promotes rapid healing of epithelial defects in neurotrophic keratopathy, improves comfort and is safe; the primary healing result was a trend (p = 0.0656).
Limitations
Very small trial (18 subjects total across arms); primary endpoint not statistically significant.
PubMed 36613994DOIFree full text
✓ Positivehuman RCTCornea · 2015

Thymosin β4 significantly improves signs and symptoms of severe dry eye in a phase 2 randomized trial.

Nine patients (12 eyes RGN-259, 6 eyes vehicle)Multicenter, randomized, double-masked, placebo-controlled phase 2 trial at 2 US sites28 days of treatment, 56-day study

Small phase 2 trial in 9 patients with severe dry eye: thymosin beta-4 eye drops reduced ocular discomfort by 35% and corneal staining by 59% vs vehicle at day 56; well tolerated.

Key resultAt day 56, RGN-259 gave a 35.1% reduction of ocular discomfort vs vehicle (P = 0.0141) and a 59.1% reduction of total corneal fluorescein staining (P = 0.0108).
Studied
Patients with severe dry eye disease, including graft-vs-host disease
Compared with
Vehicle control
Main outcome
Ocular discomfort (OSDI) and corneal fluorescein staining
Authors' conclusion
In this small trial, RGN-259 eye drops were safe, well tolerated and met key efficacy objectives with significant symptom and sign improvements at various time points.
Limitations
Very small trial (9 patients).
PubMed 25826322DOI
✓ Positivehuman RCTJ Cell Mol Med · 2021

A first-in-human, randomized, double-blind, single- and multiple-dose, phase I study of recombinant human thymosin β4 in healthy Chinese volunteers.

54 healthy subjects in the single-dose trial and 30 in the multiple-dose trial (separate trials)Randomized, double-blind, placebo-controlled, single- and multiple-dose phase I trialSingle dose or 10 days of daily dosing, observed for 28 days

In a first-in-human phase I trial, single (54 subjects) and 10-day multiple IV doses (30 subjects) of recombinant full-length thymosin beta-4 in healthy Chinese volunteers caused only mild to moderate adverse events, no serious events and no drug accumulation (this is full-length thymosin beta-4, not TB-500).

Key resultAdverse events were mild to moderate; no dose-limiting toxicities or serious adverse events
Studied
Healthy Chinese volunteers
Compared with
Placebo
Main outcome
Safety, tolerability, pharmacokinetics and anti-drug antibodies
Authors' conclusion
Recombinant human thymosin beta-4 was well tolerated and safe in healthy people and suitable for clinical study in acute myocardial infarction.
Limitations
Healthy volunteers, short term, full-length protein given intravenously rather than TB-500.
PubMed 34346165DOIFree full text
FIGURE 1: The mean ± SD of the plasma concentrations (ng/mL) of Tβ4 following single intravenous administration to healthy human subjects
FIGURE 1. From PMC8419156, CC BY (terms); resized.
✓ Positivehuman RCTAnn N Y Acad Sci · 2010

A randomized, placebo-controlled, single and multiple dose study of intravenous thymosin beta4 in healthy volunteers.

Four cohorts of 10 healthy subjects eachRandomized, placebo-controlled, ascending single- and multiple-dose studySingle dose, then daily for 14 days

In four cohorts of 10 healthy volunteers, single and 14-day daily intravenous synthetic thymosin beta-4 across a 42-1260 mg range was well tolerated, with infrequent mild or moderate adverse events and no serious events (full-length thymosin beta-4, not TB-500).

Key resultNo dose-limiting toxicity or serious adverse events over 42-1260 mg
Studied
Healthy volunteers
Compared with
Placebo
Main outcome
Safety, treatment-emergent adverse events and pharmacokinetics
Authors' conclusion
Intravenous synthetic thymosin beta-4 was well tolerated, and further development for cardiac ischemia should be considered.
Limitations
Short-term safety study in healthy volunteers; no efficacy outcome; not TB-500.
PubMed 20536472DOI
? Inconclusivehuman trialAnn N Y Acad Sci · 2010

Treatment of chronic nonhealing neurotrophic corneal epithelial defects with thymosin beta4.

Nine patients, ages 37-84Compassionate-use case series of thymosin β4 eye drops28 or 49 days of treatment, 30-day follow-up

Compassionate-use series of 9 patients with chronic neurotrophic corneal defects given thymosin beta-4 eye drops: 6 with geographic defects healed, 3 with punctate defects showed no change; no control group.

Key resultSix patients with geographic defects showed dramatic healing; 3 patients with punctate defects had no demonstrable change.
Studied
Patients with chronic nonhealing neurotrophic corneal epithelial defects
Main outcome
Healing of corneal epithelial defects
Authors' conclusion
Results from these compassionate use cases indicate Tβ4 may provide a novel topical approach to healing chronic nonhealing neurotrophic corneal ulcers.
Limitations
Uncontrolled case series, 9 patients.
PubMed 20536469DOI

Reviews

? InconclusivereviewAm J Sports Med · 2026

Peptide Supplements and Their Therapeutic Applications in Sports Medicine.

No new dataScoping review (PubMed, PRISMA)

Review of six popular sports-medicine peptides including TB-500 found claimed musculoskeletal recovery benefits unsubstantiated by human trials and advised against use outside standard care.

Studied
Literature on 6 peptides (BPC-157, TB-500, CJC-1295, MK-677, ipamorelin, GHK-Cu) for musculoskeletal recovery
Main outcome
Musculoskeletal recovery and performance in animal and human models
Authors' conclusion
67% of publications were preclinical; human data were limited and showed modest improvements at best. Claimed benefits remain unsubstantiated by human trials, and these peptides should not currently be recommended.
Limitations
Few, poorly controlled human studies; heterogeneous dosing and routes.
PubMed 42578445DOI
? InconclusivereviewPreprints.org · 2026preprint

Thymosin Beta-4 and TB-500 in Tissue Healing, Regeneration, and Musculoskeletal Repair: A Scoping Review

80 studies included from 1772 recordsScoping review (PubMed, Europe PMC, ClinicalTrials.gov through March 2026)

Preprint (not peer-reviewed): A scoping review of 80 studies found mostly in vitro and animal work on thymosin beta-4, only a single included study directly on TB-500, and limited human evidence for musculoskeletal use.

Studied
Studies of thymosin beta-4 and TB-500 in tissue healing and repair
Main outcome
Mapping of evidence by tissue category
Authors' conclusion
The literature supports interest in several repair pathways but is unevenly distributed and largely preclinical, with limited human evidence directly relevant to musculoskeletal applications.
Limitations
Preprint not yet peer-reviewed; scoping review does not assess study quality.
Europe PMC preprint

Animal & lab studies

✓ PositiveanimalJt Dis Relat Surg · 2026

Effects of BPC-157 and TB-500 on Achilles tendon healing in rats: A histopathological and biomechanical study.

Thirty-two rats, eight per groupRandomized, four-group animal study (control, BPC-157, TB-500, BPC-157 + TB-500)4 weeks

In 32 rats with repaired Achilles tendons, TB-500 and BPC-157 each improved tissue organization vs control, and TB-500 also improved tendon strength at 4 weeks; combining them added no benefit.

Key resultMaximum load to failure was higher with TB-500 than control (p < 0.05); total Bonar score lower with TB-500 (p = 0.016).
Studied
Male Sprague-Dawley rats with Achilles tendon transection and repair
Compared with
Untreated control; BPC-157 alone
Main outcome
Biomechanical maximum load to failure and histopathology (Bonar, Movin scores)
Authors' conclusion
Both BPC-157 and TB-500 were associated with improved histology and matrix organization in this exploratory rat study; TB-500 also showed a biomechanical advantage. No additive effect of combination. Preliminary.
Limitations
Exploratory rat study; dose-optimization and longer-term studies needed.
PubMed 42542926DOI
✓ PositiveanimalJ Orthop Res · 2014

Thymosin β4 administration enhances fracture healing in mice.

AnimalsAnimal study, Tβ4 vs saline i.p. injectionCallus analysed at 21 days post-fracture

In mice with fibular fractures, thymosin beta-4 injections increased callus strength by 41% and stiffness by about 25% vs saline.

Key resultTβ4-treated calluses had a 41% increase in peak force to failure (p < 0.01) and were approximately 25% stiffer (p < 0.05) than saline controls.
Studied
Mice with bilateral fibular osteotomy
Compared with
Saline
Main outcome
Fracture callus biomechanics and composition (µCT, histomorphometry)
Authors' conclusion
Enhanced biomechanical properties of fractures in Tβ4-treated mice provide novel evidence of therapeutic potential for treating bone fractures.
Limitations
Mouse study; group sizes not stated in abstract.
PubMed 25042765DOI

Verdicts are judged on each paper's own main outcome; grades run from A (strong human evidence) to D (little or none). Details are read from the abstracts, and figures are reproduced only from openly licensed full texts. Not medical advice.