Verdict card (component)
⊘ Insufficient evidence
A heptapeptide developed at the Russian Academy of Medical Sciences as a synthetic analog of tuftsin, approved in Russia for generalized anxiety disorder but not characterized in Western trial systems. The Russian-language clinical evidence shows anxiolytic effects without sedation; published Western RCT data is essentially absent. The molecule is interesting mechanistically and likely has real anxiolytic activity, but the evidence base we’d need to recommend it does not exist.
Evidence signal row
- ! Russian clinical use — approved indication for generalized anxiety
- ! No Western RCT replication of clinical efficacy claims
- ⊘ Mechanism is partially characterized but not fully understood
Our verdict (4 sentences)
Selank, like Epitalon and Semax, is a Russian-developed peptide whose evidence base is concentrated in Russian-language clinical literature and has not been independently replicated in Western pharmaceutical research. The published Russian work suggests real anxiolytic effects, plausibly through tuftsin-related immune and CNS mechanisms, possibly through enkephalin-degrading enzyme inhibition. Whether these effects survive the higher trial standards typical of Western anxiety-disorder pharmaceutical development is unknown. We give this Insufficient evidence — it likely does something, but what it does and how reliably is not characterized at the level we’d require to recommend.
Mechanism
Selank is a synthetic heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) developed at the Institute of Molecular Genetics of the Russian Academy of Sciences. It is structurally related to tuftsin (Thr-Lys-Pro-Arg), a naturally-occurring tetrapeptide fragment of immunoglobulin G with characterized immunomodulatory and CNS effects.
The proposed mechanisms (none fully proven dominant):
- Tuftsin-related receptor activity — tuftsin has known immune-cell stimulating effects and some neuroactive effects; selank is hypothesized to act through related pathways with different specificity
- Enkephalin-degrading enzyme inhibition — selank may inhibit the enzymatic breakdown of endogenous enkephalins, prolonging their endorphin-like effects
- Modulation of GABA, serotonin, and dopamine systems — proposed in Russian literature, with some animal-model support
- Interferon and cytokine modulation — immune effects also reported
The C-terminal Pro-Gly-Pro extension to the tuftsin sequence is the engineered modification that confers stability against rapid peptidase degradation. Selank’s half-life is short (estimated 5–15 minutes in plasma) but tissue effects appear longer-lasting through unclear mechanisms.
The standard administration route in Russian clinical use is intranasal spray — bypassing first-pass metabolism and providing reasonable CNS bioavailability for a short peptide.
What the evidence shows
Russian clinical research base:
- Multiple published trials in generalized anxiety disorder showing anxiolytic effect comparable to medazepam (a benzodiazepine) without the sedation and cognitive impairment
- Studies in attention disorders, chronic stress, and asthenic conditions
- Smaller body of immunomodulatory studies
The Russian evidence is real and amounts to a substantial publication record. The methodological standards vary; not all of the published trials would meet contemporary Western pharmaceutical-trial standards.
Western evidence:
- A few mechanistic studies in non-Russian labs (limited)
- No RCTs in Western institutional contexts at pharmaceutical-development standards
Why this matters:
The Russian clinical use of selank for anxiety is established in that regulatory and clinical-care context. Whether the effects translate at the same magnitude in a different patient population, with different concomitant therapies, and under different trial standards is unknown. The molecule may work as well as the Russian literature suggests; or the effect sizes may shrink under more rigorous trial conditions. We don’t know.
Dosing literature
Russian clinical use (intranasal):
- 0.15% solution, 0.3 mL (~450 mcg) intranasal, 2–3 times daily
- Course duration typically 10–14 days, sometimes extended
Gray-market protocols (Western contexts):
- Generally similar to Russian clinical doses
- Some users use subcutaneous injection rather than intranasal; bioavailability calculations vary
The intranasal route is the studied route. Subcutaneous and oral preparations sold by gray-market vendors have different bioavailability and PK that may not match the Russian clinical-evidence dose.
Risks and adverse events
In published Russian clinical reports:
- Generally well-tolerated acute profile
- Mild local irritation with intranasal administration
- No major sedation, dependence, or withdrawal effects (the distinguishing feature versus benzodiazepines)
- No significant CNS depression
The clean profile in Russian reports is part of why the molecule is interesting — anxiolytics without sedation or dependence potential are valuable.
Theoretical concerns:
- Long-term effects on enkephalin/endorphin systems are not characterized. Chronic modulation of these systems through pharmacological means is not without precedent for adaptive changes.
- Immune effects (tuftsin-related) could theoretically be relevant in patients with autoimmune conditions or recent infections; this is uncharacterized.
- Drug interactions with conventional anxiolytics, antidepressants, or sedatives are not characterized in the Russian literature in detail.
Quality concerns:
The heptapeptide structure is straightforward to synthesize. Quality of gray-market selank is variable; intranasal sprays in particular are sometimes mis-formulated (wrong concentration, contamination from the vehicle).
Regulatory status
| Region | Status | Notes |
|---|---|---|
| United States | Not approved | |
| European Union | Not approved | |
| United Kingdom | Not approved | |
| Russia | Approved (2009) | For generalized anxiety disorder; available by prescription only. Ukraine also recognizes the approval. |
| Most other markets | Not approved |
The Russian regulatory status is the only formal approval. As with Epitalon, this is real but not directly comparable to Western pharmaceutical regulatory validation.
Where to get it
We do not route readers to a fulfillment partner for selank. The Insufficient evidence verdict reflects honest uncertainty about whether the molecule works as marketed in non-Russian-clinical-context use.
For readers in Russia or in clinical relationships with practitioners familiar with the Russian peptide pharmacopeia, the legitimate access path is prescription. For Western users, the gray-market is the practical-but-not-recommended path.
(See How we make money.)
References (selected)
- Zozulia AA et al. The efficacy of Selank in the therapy of generalized anxiety disorders and neurasthenia. Zh Nevrol Psikhiatr Im S S Korsakova 2008 (Russian).
- Medvedev VE et al. Optimization of therapy of patients with anxiety-asthenic disorders using selank. Zh Nevrol Psikhiatr Im S S Korsakova 2014.
- Kolik LG et al. Selank, a novel peptide anxiolytic, exhibits anxiolytic and anti-aggressive effects in animal experiments. Bull Exp Biol Med 2014.
- Inozemtseva LS et al. Intracerebroventricular administration of the neuroprotective peptide Selank protects against the development o
Quick Facts
| Also Known As | TP-7 |
|---|---|
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Molecular Formula | C33H57N11O9 |
| Molecular Weight | 751.9 Da |
| PubChem CID | 11765600 |
Research Parameters
| Half-Life | ~30-60 minutes (estimated, based on peptide structure and administration route) |
|---|---|
| Stability | Lyophilized powder is stable for at least 24 months when stored at -20°C, protected from light and moisture. After reconstitution in bacteriostatic water, the solution should be stored at 2-8°C and is typically stable for up to 21-30 days. |
| Solubility | Bacteriostatic Water (0.9% benzyl alcohol) or Sterile Water for injection. |
| Vial Size | 5 mg |
| Storage (Lyophilized) | -20°C or below, protected from light and moisture. |
| Storage (Reconstituted) | 2-8°C (refrigerated), protected from light. Use within the recommended stability period (e.g., 21-30 days). |
| Typical Research Dose | 1500-4500 mcg per day (intranasal, in divided doses) in human research. Animal research doses vary widely by model (e.g., 50-300 mcg/kg, subcutaneous). |
| Cycle Parameters | In clinical research, daily intranasal administration for periods of 10 to 28 days is common. Specific cycle parameters (e.g., weeks on/off) are not standardized in the literature and are protocol-dependent. |
| Amino Acid Count | 7 |
Mechanism of Action
Selank's mechanism of action is multifaceted, involving modulation of both the central nervous system and the immune system. Its effects are mediated through interactions with various neurotransmitter systems, neurotrophic factors, and cytokine networks, rather than binding to a single classical receptor like GABA-A for benzodiazepines.
Serotonergic and Dopaminergic Modulation: Selank increases the expression and metabolism of serotonin in key brain regions such as the frontal cortex and hippocampus. It also influences dopamine metabolism, normalizing its levels under stress conditions, which contributes to its anxiolytic and antidepressant-like effects.
Brain-Derived Neurotrophic Factor (BDNF) Regulation: The peptide upregulates the expression of BDNF, a critical neurotrophin for neuronal survival, plasticity, and growth. This action is believed to underlie its nootropic (cognition-enhancing) and neuroprotective properties.
Immune System Modulation: As a tuftsin analog, Selank modulates the immune response. It influences the production of key cytokines, including interleukin-6 (IL-6) and interferon-gamma (IFN-γ), shifting the balance towards a more regulated immune state. This immunomodulation is thought to contribute to its anti-stress and resilience-promoting effects.
Enkephalinase Inhibition: Research suggests Selank can inhibit enzymes that degrade endogenous enkephalins (natural opioid peptides). This leads to increased levels of enkephalins in the brain, which may contribute to its anxiolytic and mild analgesic effects.
Research Applications
Anxiety and Depression Research: Selank has demonstrated significant anxiolytic and antidepressant effects in numerous animal models and human clinical trials. It reduces anxiety-like behaviors without causing sedation, muscle relaxation, or addiction, making it a valuable research compound for studying non-benzodiazepine pathways in emotional regulation.
Cognitive Function and Nootropic Research: Studies indicate Selank can improve learning and memory processes, particularly under conditions of stress or fatigue. Its ability to enhance BDNF expression positions it as a tool for researching neuroplasticity and cognitive enhancement strategies.
Immunology and Psychoneuroimmunology Research: The peptide's roots in tuftsin make it a prime candidate for investigating the bidirectional communication between the immune system and the brain. Research focuses on its ability to modulate cytokine profiles and improve immune response, especially in stress-induced immunosuppression models.
Stress Resilience and Adaptation: Selank has been shown to increase resilience to various stressors, both physical and emotional. Research explores its role in normalizing stress-induced changes in neurotransmitter levels, hormone secretion (e.g., cortisol), and immune parameters.
Safety & Side Effects
Based on clinical trial data, Selank has a favorable safety profile with low toxicity. No serious adverse events have been reported in controlled studies. Anecdotally reported side effects are rare and mild, potentially including transient dizziness or local irritation at the administration site (for nasal spray).
Theoretical concerns are minimal due to its peptide nature and endogenous analog structure, suggesting a low risk of severe off-target effects. However, as with any biologically active compound, the potential for individual hypersensitivity reactions exists. Long-term safety data beyond several weeks of continuous use are limited.
Dosage Information
This information is derived from published research literature and is for research purposes only. It does not constitute medical advice.
In human clinical studies, Selank has been administered intranasally as a 0.15% aqueous solution. Typical research doses range from 1.5 mg to 4.5 mg per day, divided into 2-3 intranasal administrations. The duration of administration in clinical trials has varied from 10 days to 2-4 weeks. Animal research often employs subcutaneous or intraperitoneal injection, with doses calculated per kilogram of body weight.
References
Zozulya, A.A., et al., The neurotropic activity of tuftsin derivative–selank. Bulletin of Experimental Biology and Medicine, 1998. 126(5): p. 500-502.
Kovalev, G.I., et al., Comparative study of the effects of Selank and benzodiazepine anxiolytics on the passive avoidance response in rats. Neuroscience and Behavioral Physiology, 2012. 42(3): p. 315-320.
Ashmarin, I.P., et al., Two faces of the same peptide–from psychotropic to neuroprotective action. Journal of Molecular Neuroscience, 2005. 27(1): p. 103-110.
Kost, N.V., et al., Effect of Selank on the expression of genes controlling serotonin and dopamine metabolism in the brain. Doklady Biological Sciences, 2002. 382: p. 36-38.
Medvedev, V.E., et al., Efficacy and safety of Selank in the treatment of anxiety disorders: results of a multicenter clinical trial. Neuroscience and Behavioral Physiology, 2014. 44(3): p. 302-307.
Myasoedov, N.F., et al., Effects of Selank on BDNF expression in the rat hippocampus. Bulletin of Experimental Biology and Medicine, 2013. 155(5): p. 612-614.