Third-Party Tested ≥98% HPLC Purity — USA Shipped

Research Comparison

TB-500 vs Thymalin

In Short

TB-500 is synthetic peptide fragment of thymosin beta-4; Thymalin is thymus-derived low-molecular-weight polypeptide complex; immunomodulatory peptide bioregulator (khavinson bioregulator class). Both are supplied as lyophilized powders for laboratory and in-vitro research use only. The table below compares their molecular data, half-life and research focus side by side.

TB-500 Thymalin
Classification Synthetic peptide fragment of thymosin beta-4 Thymus-derived low-molecular-weight polypeptide complex; immunomodulatory peptide bioregulator (Khavinson bioregulator class)
Molecular formula C212H350N56O78S C33H54N12O15
Molecular weight 4963.44 g/mol 858.864 g/mol
CAS number 77591-33-4
Research half-life Short circulating half-life in preclinical models Not well characterized in the published literature
Primary research focus Angiogenesis and blood vessel formation Immune-regulation research
Form Lyophilized powder Lyophilized powder
Price from $50.00 $72.49

TB-500

TB-500 is the synthetic version of Thymosin Beta-4, a naturally occurring 43-amino acid peptide present in virtually all human and animal cells. Its primary mechanism of action centers on sequestering G-actin monomers, which promotes actin polymerization and cell migration essential for tissue repair. TB-500 also upregulates expression of laminin-5, a key component of the basement membrane, and activates Akt (protein kinase B) signaling, which research indicates promotes cell survival and inhibits apoptosis. Published studies have demonstrated TB-500's wound healing properties in dermal repair models (Malinda et al., Journal of Investigative Dermatology, 1999) and corneal epithelium regeneration. In equine research, Thymosin Beta-4 has been extensively studied for tendon and ligament repair, with published veterinary trials showing accelerated recovery timelines. The peptide's anti-inflammatory properties appear to operate through suppression of NF-kB and reduction of pro-inflammatory cytokines including IL-1beta and TNF-alpha. Compared to BPC-157, TB-500 has a broader tissue distribution and systemic migration capability, making it a preferred research compound for widespread inflammatory conditions rather than localized injury models. The two peptides target complementary repair mechanisms, which is why they are frequently combined in research studies. Store lyophilized powder at -20C; reconstitute with bacteriostatic water and refrigerate at 2-8C for up to 28 days. TB-500 is investigated by regenerative medicine centers, veterinary research institutions, and cardiology labs studying post-ischemic tissue recovery.

Full TB-500 research guide

Thymalin

Thymalin is a polypeptide complex originally extracted from calf thymus glands, standardized as a mixture of short peptides including the dipeptide Glu-Trp (EW). Developed by Vladimir Khavinson and colleagues at the Saint Petersburg Institute of Bioregulation and Gerontology, Thymalin operates through thymic bioregulation, restoring T-cell populations and normalizing the ratio of T-helper to T-suppressor lymphocytes. It modulates thymulin production and supports immune homeostasis through gene expression changes in immunocompetent cells. Landmark cellular-aging research by Khavinson and Morozov published in Neuroendocrinology Letters reported that Thymalin use in a 6-year study of elderly subjects was associated with a 2-fold reduction in mortality rate compared to controls, alongside improvements in immune markers, endocrine function, and cardiovascular parameters. Additional studies published in Bulletin of Experimental Biology and Medicine showed restoration of melatonin production and normalization of cortisol rhythms in aged subjects receiving Thymalin. Research in animal models demonstrated increased average and maximum lifespan when Thymalin was used to aging rodents. Compared to Thymosin Alpha-1, which is a defined single-sequence peptide with extensive Western clinical data, Thymalin represents a complex bioregulatory approach rooted in the Russian peptide bioregulator tradition. Thymosin Alpha-1 has more targeted receptor-level data, while Thymalin's effects appear more systemic and multi-pathway. Both aim to restore immune competence, but through different pharmacological approaches. Lyophilized Thymalin should be stored at -20°C. Reconstitute with bacteriostatic water and store at 2-8°C, using within 3 weeks. Thymalin is primarily researched by gerontologists, immunologists studying age-related immune decline, and bioregulation scientists investigating peptide-based geroprotective interventions.

Full Thymalin research guide

Frequently Asked Questions

What is the main difference between TB-500 and Thymalin?
TB-500 is classified as synthetic peptide fragment of thymosin beta-4, while Thymalin is thymus-derived low-molecular-weight polypeptide complex; immunomodulatory peptide bioregulator (khavinson bioregulator class). They are distinct research compounds with different mechanisms — the comparison table above sets out the molecular and pharmacokinetic differences side by side.
Can TB-500 and Thymalin be studied together?
Some research protocols evaluate related peptides in combination, and research blends exist. Combination study design depends entirely on the research question and model. Both compounds are supplied for laboratory and in-vitro research use only — not for human use.
Are TB-500 and Thymalin legal to buy for research?
Both are sold in the United States as research chemicals for laboratory and in-vitro use only. Neither is FDA-approved for human use. Researchers are responsible for compliance with all applicable regulations.

Buy TB-500

From $50.00 — ≥98% HPLC, COA included.

Buy Thymalin

From $72.49 — ≥98% HPLC, COA included.

Research Use Only. This comparison summarizes published research. It is not medical advice. Neither compound is for human consumption or FDA-approved.