amifampridine   Click here for help

GtoPdb Ligand ID: 8032

Synonyms: 3,4-DAP | 3,4-diaminopyridine | Firdapse® | Ruzurgi® | Zenas®
Approved drug PDB Ligand
amifampridine is an approved drug (EMA (2009), FDA (2018))
Compound class: Synthetic organic
Comment: Amifampridine is a potassium channel blocker.
2D Structure
Click here for help

2D Structure

An image of the ligand's 2D structure. For small molecules with SMILES these are drawn using the NCI/CADD Chemical Identifier Resolver. Click on the image to access the chemical structure search tool with the ligand pre-loaded in the structure editor. For other types of ligands, e.g. longer nucleotides and peptides, a manually drawn representation of the molecule may be provided.

✖
Click here for structure editor
Physico-chemical Properties
Click here for help

Physico-chemical Properties

Calculated molecular properties are available for small molecules and natural products (not peptides). Properties were generated using the CDK toolkit. All properties were selected to enable the prediction of the Lipinski Rule-of-Five profile or ‘druglikeness’ for each ligand. For more info on each category see the help pages.

✖
Hydrogen bond acceptors 3
Hydrogen bond donors 2
Rotatable bonds 0
Topological polar surface area 64.93
Molecular weight 109.06
XLogP -0.86
No. Lipinski's rules broken 0
SMILES / InChI / InChIKey
Click here for help

SMILES / InChI / InChIKey

SMILES (Simplified Molecular Input Line Entry Specification) A specification for unambiguously describing the structure of chemical molecules using short ASCII strings. Canonical SMILES specify a unique representation of the 2D structure without chiral or isotopic specifications. Isomeric SMILES include chiral specification and isotopes.

Standard InChI (IUPAC International Chemical Identifier) and InChIKey InChI is a non-proprietary, standard, textual identifier for chemical substances designed to facilitate linking of information and database searching. An InChIKey is a simplified version of a full InChI, designed for easier web searching.

✖
Canonical SMILES Nc1cnccc1N
Isomeric SMILES Nc1cnccc1N
InChI InChI=1S/C5H7N3/c6-4-1-2-8-3-5(4)7/h1-3H,7H2,(H2,6,8)
InChI Key OYTKINVCDFNREN-UHFFFAOYSA-N
No information available.
Summary of Clinical Use Click here for help
Amifampridine was approved in the EU as a treatment for the orphan disease, Lambert-Eaton myasthenic syndrome (LEMS) in 2009. FDA approval for this indication was granted in November 2018. It may be useful for treatment other congenital myasthenic syndromes. The FDA authorised use in paediatric LEMS patients of 6-17 years of age in May 2019.
Mechanism Of Action and Pharmacodynamic Effects Click here for help
Lambert-Eaton myasthenic syndrome (LEMS) arises from the autogenic destruction of pre-synaptic proteins, in particular P/Q‐type voltage-gated calcium channels, at the neuromuscular junction. The damage results in reduced release of acetylcholine into the synaptic cleft, impairing muscle contraction which would be the normal response to activation of post-synpatic acetylcholine receptors. Amifampridine acts to block pre-synaptic potassium channels, thereby extending the duration of the action potential, and increasing acetylcholine release. The subsequent increase in acetylcholine receptor activation improves muscle tone.
LEMS often occurs as a paraneoplastic condition [1] in cancer patients or in patients with other autoimmune diseases [2,4].