Summary
Thymosin alpha-1 is a 28-amino-acid peptide originally isolated from thymus tissue, the gland where T cells mature. The synthetic form is called thymalfasin. It has been through a large clinical programme as an immune modulator, mostly outside the UK, US and Australia, and is not an approved medicine in any of the three.
What it targets
Thymosin alpha-1 is described in the literature as modulating T-cell activity rather than acting on a single receptor, and trials have used CD4+ T-cell counts as a marker of that effect. The strongest evidence linked here is also the most sobering: a phase 3 trial in 1,106 adults with sepsis across 22 Chinese hospitals found no significant difference in 28-day mortality against placebo, and no difference on any secondary or safety outcome. In COVID-19, a 49-patient open-label pilot found faster CD4+ T-cell recovery in treated patients on low-flow oxygen but no significant difference in clinical recovery, while a pooled analysis of eight studies reported lower mortality with very high disagreement between the studies pooled. A separate meta-analysis of 39 trials in COPD flare-ups reported better lung function and shorter hospital stays with the drug added to routine care. The pattern across the evidence is that pooled analyses of smaller studies look favourable while the single largest well-designed trial was negative.
Clinical Research
Suppliers stocking Thymosin alpha-1
15 of the 30 listed suppliers. Each row opens its full listing.