RESEARCH MONOGRAPH · KDC-MN-065

Afobazole

May 9, 2026 Kodiac biolabs Research Revised May 30, 2026 2 min read

Our opinion on this compound

68/100

Sigma-1 anxiolytic with a unique non-sedating profile and surprisingly clean mechanism story

Afobazole is genuinely interesting and we think undersold. The 2-mercaptobenzimidazole scaffold (developed by the Zakusov group at the State Institute of Pharmacology in Moscow) is one of the few anxiolytic mechanisms in clinical use that doesn't touch the GABA-benzodiazepine site directly, so you dont get the sedation, tolerance, or withdrawal profile of clonazepam-class drugs.

The mechanism is sigma-1 receptor agonism plus melatonin MT1/MT3 modulation plus some MAO-A reversible inhibition. The sigma-1 agonism is the part that matters; it's the same target that dimethyltryptamine, fluvoxamine, and dextromethorphan touch, and it modulates ER-mitochondria calcium signaling, IP3R function, and BDNF release. Hayashi and Su mapped a lot of this in the early 2000s. So afobazole isn't acting on classical anxiolytic targets, it's working through a chaperone-receptor pathway that affects neuroplasticity over weeks rather than minutes.

What we like: the Russian phase 3 data on generalized anxiety is reasonable quality, the non-sedation profile genuinely holds up in head-to-head comparisons, and there's preclinical work showing neuroprotection in stroke and Alzheimer models that fits the sigma-1 story. The compound has been in widespread Russian use since 2006 with a clean post-marketing safety record across millions of patient-years.

What we dont like: again, western trial replication is essentially zero. Seredenin's group has published a lot but it's mostly in-house, and we'd love to see a properly powered placebo-controlled GAD trial run outside Russia. The MAO-A reversible inhibition raises minor interaction concerns, though clinically these haven't shown up much.

Sourcing is fine, the benzimidazole synthesis is standard organic chemistry and HPLC purity is achievable at the gram scale without much trouble. Most research-grade afobazole is reasonably pure if you stick to vendors that publish actual chromatograms.

Honestly, for studying sigma-1 anxiolysis in animal models, this is a much better tool compound than people give it credit for. The mechanism is novel enough to matter, and the human safety data (even if mostly Russian) is genuinely encouraging.

Evidence: 55
Mechanism: 78
Reliability: 65
Safety: 82
Sourcing: 72
Value: 68
Signal: 62
Staying power: 65

Plain-language summary Intrigue 68 / 100

Afobazole is a Russian anxiolytic that works through sigma-1 and other receptors rather than the GABA system. It is approved in Russia for generalized anxiety without sedation or dependence. Not stocked by Kodiac. This monograph is provided for research and educational reference.

Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

Sigma-1 receptor agonist anxiolytic

A Russian-developed selective sigma-1 receptor agonist anxiolytic without sedation, dependence, or cognitive impairment liability.

Abstract

Afobazole (Afobazol; 2-mercaptobenzimidazole; CAS 173352-21-1; molecular formula C11H14N4OS; molecular weight 250.32) is a selective sigma-1 receptor agonist anxiolytic developed at the Zakusov Institute of Pharmacology in Russia in the 1990s and approved in Russia as Afobazole for generalized anxiety disorder. The compound is structurally distinct from benzodiazepines and produces anxiolytic effects without the sedation, dependence, withdrawal syndrome, cognitive impairment, or motor coordination liability characteristic of GABA-A allosteric modulators. Mechanism is sigma-1 receptor agonism with secondary stabilization of inositol-1,4,5-trisphosphate receptor function and enhancement of NGF and BDNF expression. The clinical evidence base is largely Russian-language; effect sizes in generalized anxiety disorder are modest but consistent. Pharmacokinetics: plasma half-life 1 to 2 hours, but the anxiolytic effect persists substantially longer. Reported research dose ranges in the literature are described in the source monograph.

Mechanism of action

Selective sigma-1 receptor agonist; IP3 receptor stabilization; NGF/BDNF upregulation. No GABA-A activity.

Reported research dose ranges

30 to 60 mg (reported research dose range).

References

Seredenin SB, Voronin MV. Neuroreceptor mechanisms of afobazole action. Bull Exp Biol Med 2009.

Read the full monograph

The full reference document covers compound identification, discovery and developmental history, mechanism of action, pharmacokinetics, reported research dose ranges, sourcing and quality verification, reconstitution and handling, stack interaction considerations, and a curated reference list. Available as a research-use-only PDF download.

KDC-MN-065

The full reference document is provided strictly for research use only. It reports research dose ranges from the published literature, not instructions for use in humans or animals.

Download PDF →

FOR RESEARCH USE ONLY. Not for medical, diagnostic, or therapeutic purposes. Not for human consumption. All information is provided for research and educational purposes only.

Kodiac sells research compounds for investigative use only.

Afobazole

Abstract

Mechanism of action

Reported research dose ranges

References

Read the full monograph

Quick actions

Categories

Help and policies

Abstract

Mechanism of action

Reported research dose ranges

References

Read the full monograph

Adjacent monographs