Eptapirone

Last updated
Eptapirone
Eptapirone.png
Clinical data
Routes of
administration
Oral
ATC code
  • none
Legal status
Legal status
  • In general: uncontrolled
Pharmacokinetic data
Elimination half-life 2 hours
Identifiers
  • 4-methyl-2-[4-(4-pyrimidin-2-ylpiperazin-1-yl)butyl]-1,2,4-triazine-3,5-dione
CAS Number
PubChem CID
ChemSpider
UNII
CompTox Dashboard (EPA)
Chemical and physical data
Formula C16H23N7O2
Molar mass 345.407 g·mol−1
3D model (JSmol)
  • Cn1c(=O)cnn(c1=O)CCCCN2CCN(CC2)c3ncccn3
  • InChI=1S/C16H23N7O2/c1-20-14(24)13-19-23(16(20)25)8-3-2-7-21-9-11-22(12-10-21)15-17-5-4-6-18-15/h4-6,13H,2-3,7-12H2,1H3
  • Key:NMYAHEULKSYAPP-UHFFFAOYSA-N

Eptapirone (F-11,440) is a very potent and highly selective 5-HT1A receptor full agonist of the azapirone family. [1] [2] Its affinity for the 5-HT1A receptor was reported to be 4.8 nM (Ki) (or 8.33 (pKi)), and its intrinsic activity approximately equal to that of serotonin (i.e., 100%). [1]

Contents

Eptapirone and related high-efficacy 5-HT1A full and super agonists such as befiradol and F-15,599 were developed under the hypothesis that the maximum exploitable therapeutic benefits of 5-HT1A receptor agonists might not be able to be seen without the drugs employed possessing sufficiently high intrinsic activity at the receptor. As 5-HT1A receptor agonism, based on animal and other research, looked extremely promising for the treatment of depression from a theoretical perspective, this idea was developed as a potential explanation for the relatively modest clinical effectiveness seen with already available 5-HT1A receptor agonists like buspirone and tandospirone, which act merely as weak-to-moderate partial agonists of the receptor. [1] [2] [3] [4] [5]

Animal studies

In the Porsolt forced swimming test, eptapirone was found to suppress immobility more robustly than buspirone, ipsapirone, flesinoxan, paroxetine, and imipramine, which was suggestive of strong antidepressant-like effects. [1] In this assay, unlike the other drugs screened, buspirone actually increased the immobility time with a single administration, while repeated administration decreased it, an effect that may have been related to buspirone's relatively weak intrinsic activity (~30%) at the 5-HT1A receptor and/or its preferential activation of 5-HT1A somatodendritic autoreceptors over postsynaptic receptors. [1]

After repeated administration, high dose paroxetine was able to rival the reduction in immobility seen with eptapirone. However, efficacy was seen on the first treatment with eptapirone, which suggested that eptapirone may have the potential for a more rapid onset of antidepressant effectiveness in comparison. [1] Imipramine was unable to match the efficacy of eptapirone or high dose paroxetine, which was probably the result of the fact that higher doses were fatal. [1]

In the conflict procedure, eptapirone produced substantial increases in punished responding without affecting unpunished responding, which was suggestive of marked anxiolytic-like effects. [1] In addition, the efficacy of eptapirone in this assay was more evident than that of buspirone, ipsapirone, and flesinoxan. [1]

Human studies

Eptapirone has been assayed in humans in preclinical trials at an oral dose of 1.5 mg. [6] [7] In these studies, eptapirone reduced body temperature, prolonged REM sleep, increased cortisol and growth hormone levels, and produced side effects such as dizziness and drowsiness while being overall well tolerated. [6] [7] It peaked rapidly within 30–60 minutes and had an estimated half-life of two hours, with a total duration of approximately three hours. [6] [7]

See also

Related Research Articles

An anxiolytic is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxiety disorders and their related psychological and physical symptoms.

Azapirone Drug class of psycotropic drugs

Azapirones are a class of drugs used as anxiolytics, antidepressants, and antipsychotics. They are commonly used as add-ons to other antidepressants, such as selective serotonin reuptake inhibitors (SSRIs).

<span class="mw-page-title-main">Buspirone</span> Medication used to treat anxiety disorders

Buspirone, sold under the brand name Buspar, among others, is a medication primarily used to treat anxiety disorders, particularly generalized anxiety disorder. Benefits support its short-term use. It is taken by mouth, and it may take up to four weeks to have an effect.

<span class="mw-page-title-main">Pindolol</span> Chemical compound

Pindolol, sold under the brand name Visken among others, is a nonselective beta blocker which is used in the treatment of hypertension. It is also an antagonist of the serotonin 5-HT1A receptor, preferentially blocking inhibitory 5-HT1A autoreceptors, and has been researched as an add-on therapy to selective serotonin reuptake inhibitors (SSRIs) in the treatment of depression.

<span class="mw-page-title-main">Trimipramine</span> Antidepressant

Trimipramine, sold under the brand name Surmontil among others, is a tricyclic antidepressant (TCA) which is used to treat depression. It has also been used for its sedative, anxiolytic, and weak antipsychotic effects in the treatment of insomnia, anxiety disorders, and psychosis, respectively. The drug is described as an atypical or "second-generation" TCA because, unlike other TCAs, it seems to be a fairly weak monoamine reuptake inhibitor. Similarly to other TCAs however, trimipramine does have antihistamine, antiserotonergic, antiadrenergic, antidopaminergic, and anticholinergic activities.

5-HT<sub>1A</sub> receptor Serotonin receptor protein distributed in the cerebrum and raphe nucleus

The serotonin 1A receptor is a subtype of serotonin receptor, or 5-HT receptor, that binds serotonin, also known as 5-HT, a neurotransmitter. 5-HT1A is expressed in the brain, spleen, and neonatal kidney. It is a G protein-coupled receptor (GPCR), coupled to the Gi protein, and its activation in the brain mediates hyperpolarisation and reduction of firing rate of the postsynaptic neuron. In humans, the serotonin 1A receptor is encoded by the HTR1A gene.

8-OH-DPAT Chemical compound

8-OH-DPAT is a research chemical of the aminotetralin chemical class which was developed in the 1980s and has been widely used to study the function of the 5-HT1A receptor. It was one of the first major 5-HT1A receptor full agonists to be discovered.

WAY-100635 Chemical compound

WAY-100635 is a piperazine drug and research chemical widely used in scientific studies. It was originally believed to act as a selective 5-HT1A receptor antagonist, but subsequent research showed that it also acts as potent full agonist at the D4 receptor. It is sometimes referred to as a silent antagonist at the former receptor. It is closely related to WAY-100135.

Flesinoxan Chemical compound

Flesinoxan (DU-29,373) is a potent and selective 5-HT1A receptor partial/near-full agonist of the phenylpiperazine class. Originally developed as a potential antihypertensive drug, flesinoxan was later found to possess antidepressant and anxiolytic effects in animal tests. As a result, it was investigated in several small human pilot studies for the treatment of major depressive disorder, and was found to have robust effectiveness and very good tolerability. However, due to "management decisions", the development of flesinoxan was stopped and it was not pursued any further.

<span class="mw-page-title-main">Quipazine</span> Chemical compound

Quipazine is a serotonergic drug of the piperazine group which is used in scientific research. It was originally intended as an antidepressant but never developed for medical use.

SB-399885 Chemical compound

SB-399885 is a drug which is used in scientific research. It acts as a potent, selective and orally active 5-HT6 receptor antagonist, with a Ki of 9.0nM. SB-399885 and other 5-HT6 antagonists show nootropic effects in animal studies, as well as antidepressant and anxiolytic effects which are comparable to and synergistic with drugs such as imipramine and diazepam, and have been proposed as potential novel treatments for cognitive disorders such as schizophrenia and Alzheimer's disease.

Befiradol Chemical compound

Befiradol is an experimental drug being studied for the treatment of levodopa-induced dyskinesia. It is a potent and selective 5-HT1A receptor full agonist.

<span class="mw-page-title-main">Pyrimidinylpiperazine</span> Chemical compound

1-(2-Pyrimidinyl)piperazine (1-PP, 1-PmP) is a chemical compound and piperazine derivative. It is known to act as an antagonist of the α2-adrenergic receptor (Ki = 7.3–40 nM) and, to a much lesser extent, as a partial agonist of the 5-HT1A receptor (Ki = 414 nM; Emax = 54%). It has negligible affinity for the dopamine D2, D3, and D4 receptors (Ki > 10,000 nM) and does not appear to have significant affinity for the α1-adrenergic receptors. Its crystal structure has been determined.

Umespirone Chemical compound

Umespirone (KC-9172) is a drug of the azapirone class which possesses anxiolytic and antipsychotic properties. It behaves as a 5-HT1A receptor partial agonist (Ki = 15 nM), D2 receptor partial agonist (Ki = 23 nM), and α1-adrenoceptor receptor antagonist (Ki = 14 nM), and also has weak affinity for the sigma receptor (Ki = 558 nM). Unlike many other anxiolytics and antipsychotics, umespirone produces minimal sedation, cognitive/memory impairment, catalepsy, and extrapyramidal symptoms.

Adatanserin Chemical compound

Adatanserin is a mixed 5-HT1A receptor partial agonist and 5-HT2A and 5-HT2C receptor antagonist. It was under development by Wyeth as an antidepressant but was ultimately not pursued.

<span class="mw-page-title-main">Roxindole</span> Dopaminergic & serotonergic drug developed for schizophrenia treatment

Roxindole (EMD-49,980) is a dopaminergic and serotonergic drug which was originally developed by Merck KGaA for the treatment of schizophrenia. In clinical trials its antipsychotic efficacy was only modest but it was unexpectedly found to produce potent and rapid antidepressant and anxiolytic effects. As a result, roxindole was further researched for the treatment of depression instead. It has also been investigated as a therapy for Parkinson's disease and prolactinoma.

F-15,599 Chemical compound

F-15,599, also known as NLX-101, is a potent and selective 5-HT1A receptor full agonist. It displays functional selectivity by strongly activating 5-HT1A receptors in the postsynaptic prefrontal cortex while having little effect on somatodendritic autoreceptors in the raphe nucleus. As a result, it has been touted as a preferential postsynaptic 5-HT1A receptor agonist and has been investigated as a novel potential antidepressant.

S-14671 Chemical compound

S-14671 is a naphthylpiperazine derivative which acts as a 5-HT1A receptor agonist (pKi = 9.3) with high efficacy and exceptional in vivo potency, and also as a 5-HT2A and 5-HT2C receptor antagonist (both are pKi = 7.8). It displays only low and non-significant affinity for 5-HT1B and 5-HT3 sites.

<span class="mw-page-title-main">Brexpiprazole</span> Atypical antipsychotic

Brexpiprazole, sold under the brand name Rexulti among others, is an atypical antipsychotic. It is a dopamine D2 receptor partial agonist and has been described as a "serotonin–dopamine activity modulator" (SDAM). The drug was approved by the U.S. Food and Drug Administration (FDA) on July 10, 2015, for the treatment of schizophrenia, and as an adjunctive treatment for depression. It has been designed to provide improved efficacy and tolerability (e.g., less akathisia, restlessness and/or insomnia) over established adjunctive treatments for major depressive disorder (MDD).

References

  1. 1 2 3 4 5 6 7 8 9 Koek W, Patoiseau JF, Assié MB, et al. (October 1998). "F 11440, a potent, selective, high efficacy 5-HT1A receptor agonist with marked anxiolytic and antidepressant potential". The Journal of Pharmacology and Experimental Therapeutics. 287 (1): 266–83. PMID   9765347.
  2. 1 2 Prinssen EP, Colpaert FC, Koek W (October 2002). "5-HT1A receptor activation and anti-cataleptic effects: high-efficacy agonists maximally inhibit haloperidol-induced catalepsy". European Journal of Pharmacology. 453 (2–3): 217–21. doi:10.1016/S0014-2999(02)02430-5. PMID   12398907.
  3. Celada P, Bortolozzi A, Artigas F (September 2013). "Serotonin 5-HT1A receptors as targets for agents to treat psychiatric disorders: rationale and current status of research". CNS Drugs. 27 (9): 703–16. doi:10.1007/s40263-013-0071-0. hdl:10261/88633. PMID   23757185. S2CID   31931009.
  4. Koek W, Vacher B, Cosi C, et al. (May 2001). "5-HT1A receptor activation and antidepressant-like effects: F 13714 has high efficacy and marked antidepressant potential". European Journal of Pharmacology. 420 (2–3): 103–12. doi:10.1016/S0014-2999(01)01011-1. PMID   11408031.
  5. Maurel JL, Autin JM, Funes P, Newman-Tancredi A, Colpaert F, Vacher B (October 2007). "High-efficacy 5-HT1A agonists for antidepressant treatment: a renewed opportunity". Journal of Medicinal Chemistry. 50 (20): 5024–33. doi:10.1021/jm070714l. PMID   17803293.
  6. 1 2 3 Wilson SJ, Bailey JE, Rich AS, et al. (November 2005). "The use of sleep measures to compare a new 5HT1A agonist with buspirone in humans". Journal of Psychopharmacology. 19 (6): 609–13. doi:10.1177/0269881105058775. PMID   16272182. S2CID   34590219.
  7. 1 2 3 Wilson SJ, Bailey JE, Nutt DJ (June 2005). "Dizziness produced by a potent 5HT(1A) receptor agonist (eptapirone) is not due to postural hypotension". Psychopharmacology. 179 (4): 895–6. doi:10.1007/s00213-004-2111-4. PMID   15619110. S2CID   27804035.