Retigabine, also known as Ezogabine, is a synthetic anticonvulsant and potassium-channel modulator. It acts primarily by opening neuronal KCNQ (Kv7) potassium channels, helping stabilize neuronal membrane potential and reduce neuronal excitability.
Retigabine is a small-molecule pharmaceutical active ingredient. The free-base compound has CAS Number 150812-12-7, molecular formula C16H18FN3O2, and molecular weight 303.33 g/mol.
The pharmaceutical salt is Retigabine Dihydrochloride, with CAS Number 150812-13-8, molecular formula C16H18FN3O2·2HCl, and molecular weight 376.25 g/mol.
Product Name: Retigabine
API Category: Neurological / CNS API
Therapeutic Class: Anticonvulsant
Drug Class: Potassium Channel Opener
CAS Number: 150812-12-7
Molecular Formula: C16H18FN3O2
Molecular Weight: 303.33 g/mol
PubChem CID: 121892
ChEBI: CHEBI:161945
ChEMBL: CHEMBL41355
UNII: 12G01I6BBU
Synonyms: Ezogabine, D-23129, D-20443, Retigabine
Pharmaceutical Salt: Retigabine Dihydrochloride
Dihydrochloride CAS: 150812-13-8
Dihydrochloride Molecular Weight: 376.25 g/mol
Retigabine is identified as the INN, while ezogabine is the USAN.
Retigabine is a substituted aniline carbamate containing a fluorobenzylamino group. PubChem describes it as a carbamate ester, organofluorine compound, substituted aniline and secondary amino compound.
The free base has a molecular weight of 303.33 g/mol and molecular formula C16H18FN3O2. The compound is structurally distinct from the dihydrochloride salt, which has a molecular weight of 376.25 g/mol.
Retigabine is a potassium-channel opener and was developed as an anticonvulsant for epilepsy. It has activity at KCNQ2–KCNQ5 potassium channels.
Retigabine has been used as an anticonvulsant for the treatment of partial-onset seizures in adults with epilepsy.
Its pharmaceutical and analytical applications include:
Retigabine acts as a positive allosteric modulator and opener of neuronal KCNQ/Kv7 potassium channels, particularly KCNQ2–KCNQ5 channels.
Opening these potassium channels increases potassium conductance and promotes membrane stabilization. This reduces neuronal excitability and contributes to the anticonvulsant effect of the compound.
Retigabine API quality assessment can include identity, assay, related substances and other applicable pharmaceutical quality attributes.
Analytical control may include:
For Retigabine Dihydrochloride, commercial analytical reference standards report HPLC purity specifications of ≥98.0%, but this should not automatically be treated as a universal pharmacopoeial API release specification.
Retigabine API manufacturing involves controlled chemical synthesis followed by purification and isolation of the active pharmaceutical ingredient or its dihydrochloride salt.
Manufacturing controls may include:
For the dihydrochloride form, controlled salt formation and characterization are important to ensure the correct chemical form and consistent quality.
Retigabine API should be packaged in suitable pharmaceutical-grade containers that protect the material from contamination, moisture and inappropriate environmental exposure.
For Retigabine Dihydrochloride reference material, storage at −20°C is reported by commercial analytical-standard sources. This should not automatically be adopted as the bulk API storage specification without supporting stability data.
The final API storage condition should be established according to validated stability data and the approved product specification.
Typical pharmaceutical API documentation may include:
Retigabine requires controlled chemical synthesis, purification and analytical characterization to ensure consistent pharmaceutical quality.
A qualified Retigabine API Manufacturer in India should maintain appropriate controls over raw materials, synthesis, impurity formation, purification, drying, analytical testing and batch documentation.
For Retigabine Dihydrochloride, additional controls should ensure correct salt formation and consistent chemical identity.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.1% |
| Individual Impurity | NMT 1.0% |
| Total Impurities | NMT 2.0% |
| Water Content | NMT 1.0% |