data + articles · 6 listed
newest 2020spec sheet11 rows
Adatanserin is an azapirone-like compound developed by Wyeth (as WY-50324) as a combined anxiolytic and antidepressant. Structurally it is an adamantane bolted onto a pyrimidinylpiperazine, the same piperazine motif found in buspirone. Pharmacologically it does two things at once: it partially activates the serotonin 5-HT1A receptor and blocks the 5-HT2 (chiefly 5-HT2A) receptor, a dual profile thought to combine calming and mood-lifting actions. It reached early development but was not marketed; the published work is preclinical, from the 1990s and a few later chemistry papers.
- Dual 5-HT1A partial-agonist plus 5-HT2A-antagonist profile in one molecule
- Buspirone-like anxiolytic action without a benzodiazepine mechanism
- Antidepressant-like activity in standard rodent screens
- Showed neuroprotective glutamate-sparing effects in a brain-slice model
- Theoretical serotonin-syndrome risk with other serotonergic drugs
- Possible azapirone-type effects (lightheadedness, nausea) by class analogy
Mechanism
Adatanserin came out of a Wyeth medicinal-chemistry program on adamantyl aryl- and heteroarylpiperazines. In binding and behavioral screens it showed high affinity for the receptor and moderate affinity for the 5-HT2 receptor, and functionally it behaved as a 5-HT1A partial plus a 5-HT2 ; that combination, together with anxiolytic activity in a conflict model, is what pushed it into development as a dual anxiolytic/antidepressant [1]. The partial- arm links it to the azapirone class (buspirone and relatives), where turning up 5-HT1A signaling underlies both the anti-anxiety and, over time, antidepressant effects [3].
The two arms were teased apart in animal work. In a forced-swim antidepressant test, the partial WY-50324 reduced immobility much like a full agonist or a tricyclic antidepressant, and the effect tracked with 5-HT1A efficacy [3]. In a pigeon conflict (anti-punishment) test of anxiety, adatanserin produced anti-anxiety-like effects comparable to the classic 8-OH-DPAT, standing out among several mixed 5-HT1A/5-HT2 compounds tested [4]. And in a brain-slice model of chemically induced ischemia, adatanserin cut the harmful outflow of ; notably, that protection was reversed by a 5-HT2 but not by a blocker, implying the -blocking arm carried much of that particular effect [2]. Later chemistry, such as a thio-analog (thioadatanserin), reproduced the same dual pharmacology of partial agonism plus antagonism [5].
Honest caveats: adatanserin was never approved, human efficacy was never established in the public literature, and some of the citations here concern its metabolism and analogs rather than clinical outcomes [6]. So the dual-receptor mechanism is well supported preclinically, but its real-world usefulness in people is unproven.
receptor fingerprint
receptorpartial agonist
receptorantagonist
Anxiety / conflict behaviorreduces (anti-punishment effect)
receptorlow affinity (relatively selective)
Safetyrisks and cautions, not medical advice
Adatanserin is an unapproved, investigational compound with no established human safety or dosing information, so anything here is preclinical. Azapirone-type 5-HT1A agents are generally considered non-sedating and low in dependence risk compared with benzodiazepines, but that is a class generalization, not proven for adatanserin. As a serotonergic drug it would carry theoretical serotonin-syndrome risk if combined with MAOIs, SSRIs, or other strongly serotonergic agents. Not a validated treatment and not for self-experimentation.
Subjective profileweighing the evidence above
A well-designed dual 5-HT1A and 5-HT2A molecule that never got tested in people, so the anxiolytic case rests entirely on 1990s rodent screens. Buspirone does much the same job with decades of human data behind it; this one stays a lab curiosity.
Resources
This entry is here for reference.
Research
- 1993first citedAntidepressant-like activity of compounds with varying efficacy at 5-HT1A receptors.
- 2020most recentSynthesis and biological evaluation of thioadatanserin and its dialkylated products as partial…
- 1.Synthesis and SAR of adatanserin: novel adamantyl aryl- and heteroarylpiperazines with dual serotonin 5-HT(1A) and 5-HT(2) activity as potential anxiolytic and antidepressant agents.
- 2.Attenuation of ischemic efflux of endogenous amino acids by the novel 5-HT(1A)/5-HT(2) receptor ligand adatanserin.
- 3.Antidepressant-like activity of compounds with varying efficacy at 5-HT1A receptors.
- 4.Pharmacological characterization of in vivo properties of putative mixed 5-HT1A agonist/5-HT2A/2C antagonist anxiolytics. I. Antipunishment effects in the pigeon.
- 5.Synthesis and biological evaluation of thioadatanserin and its dialkylated products as partial 5-HTR(1A) agonists and 5-HTR(2A) antagonists for potential use in depression and anxiety disorders.
- 6.Rapid drug metabolite profiling using fast liquid chromatography, automated multiple-stage mass spectrometry and receptor-binding.
6 listed here; entry last updated August 2026
Reviews
My notesprivate to this device
FAQ
Is adatanserin an approved medicine?
No. Wyeth advanced it into early development as WY-50324, but it was never marketed and there is no published proof of efficacy in people.
How does it compare to buspirone?
Both share the pyrimidinylpiperazine core and 5-HT1A partial agonism, so both are azapirone-style. Adatanserin adds meaningful 5-HT2A blockade, which is proposed to broaden it toward antidepressant as well as anxiolytic effects.
What does 5-HT1A partial agonism mean in plain terms?
It gently turns up a specific serotonin receptor rather than flooding the system. That measured activation is the basis of the slow, non-sedating anxiety relief seen with this class.
Why block 5-HT2A at the same time?
Blocking 5-HT2A is associated with mood benefit and, in one model, with reducing harmful glutamate release. Pairing that with 5-HT1A activation was the whole design rationale.
Limitations of the evidence
- No human safety data; investigational only
- Long-term effects unknown
Adverse effects
- Theoretical serotonin-syndrome risk with other serotonergic drugs
- Possible azapirone-type effects (lightheadedness, nausea) by class analogy