Donitriptan (INNTooltip International Nonproprietary Name; developmental code name F-11356) is a triptan drug which was investigated as an antimigraine agent but was never marketed. It acts as a selective serotonin 5-HT1B and 5-HT1D receptor agonist. The drug reached phase 2 clinical trials prior to the discontinuation of its development.

Pharmacology

Donitriptan activities
TargetAffinity (Ki, nM)
5-HT1A12–25 (Ki) 182–1,150 (EC50Tooltip half-maximal effective concentration)
5-HT1B0.08–0.36 (Ki) 0.10–1.8 (EC50) 94–100% (EmaxTooltip maximal efficacy)
5-HT1D0.06–0.48 (Ki) 0.27–0.83 (EC50) 97–99% (Emax)
5-HT1E1,150–1,700 (Ki) >10,000 (EC50)
5-HT1F3,390–6,610 (Ki) >10,000 (EC50)
5-HT2A182–447 (Ki) 7.9 (EC50)
5-HT2B813 (Ki) 25 (EC50)
5-HT2C575 (Ki) (rat) ND (EC50)
5-HT3>10,000 (mouse)
5-HT42,000 (guinea pig)
5-HT5A813
5-HT62,340
5-HT7372–617 (Ki) 5,890 (EC50)
α1Aα1DND
α2Aα2CND
β1β3ND
D1>10,000
D2>10,000
D3D5ND
H1>10,000
H2>10,000
H3, H4ND
M1M5ND
mACh>10,000
I1, I2>1,000
σ1, σ2ND
TAAR1Tooltip Trace amine-associated receptor 1ND
SERTTooltip Serotonin transporter>1,000 (IC50Tooltip half-maximal inhibitory concentration)
NETTooltip Norepinephrine transporter>1,000 (IC50)
DATTooltip Dopamine transporter>1,000 (IC50)
MAO-ATooltip Monoamine oxidase A>10,000
MAO-BTooltip Monoamine oxidase B>10,000
Notes: The smaller the value, the more avidly the drug binds to the site. All proteins are human unless otherwise specified. Refs:

Donitriptan acts as a high-affinity, high-efficacy near-full agonist of the serotonin 5-HT1B (Ki = 0.079–0.40nM; EmaxTooltip maximal efficacy = 94%) and 5-HT1D receptors (Ki = 0.063–0.50nM; Emax = 97%), and is among the most potent of the triptan series of drugs. It is also notable and unique among most of the triptans in being a potent serotonin 5-HT2A receptor agonist (EC50Tooltip half-maximal effective concentration = 7.9nM), albeit with about one or two orders of magnitude lower activational potency than at the serotonin 5-HT1B and 5-HT1D receptors.

Chemistry

Donitriptan is a tryptamine derivative, a 5-substituted derivative of tryptamine and 5-methoxytryptamine, and an analogue of the psychedelic drugs dimethyltryptamine (DMT) and 5-MeO-DMT.

The predicted log P of donitriptan is 1.32 to 2.2.

History

Donitriptan was being developed in France by bioMérieux-Pierre Fabre and made it to phase II clinical trials in Europe before development was discontinued.

See also