Riluzole is a medication used to treat amyotrophic lateral sclerosis (ALS) and other motor neuron diseases. Riluzole delays the onset of ventilator-dependence or tracheostomy in some people and may increase survival by two to three months. Riluzole is available as 50 mg oral tablets and as a 5 mg/mL oral suspension. Chemically described as 6-(trifluoromethoxy)-2-aminobenzothiazole (CAS 1744-22-5), riluzole has a molecular weight of about 234.2 g/mol, is sparingly soluble in water and more soluble in organic solvents such as ethanol and dimethyl sulfoxide, and is handled and stored as a crystalline API under recommended conditions to limit degradation. Formulation considerations include controlling particle size distribution for content uniformity, maintaining low moisture uptake, and applying validated analytical methods such as HPLC-UV and LC-MS for assay, related substances and stability-indicating impurity profiling.
Parent: Riluzole
Parent: Riluzole
Parent: Riluzole
Parent: Riluzole
Typical quality control limits applied to riluzole active pharmaceutical ingredient are conservative to support patient safety: individual identified related substances are commonly limited to not more than 0.10 to 0.30% w/w, individual unspecified impurities are often reported at or above 0.05% w/w and typically limited to ≤0.10% w/w, and total impurities are generally controlled to ≤1.0% w/w in the finished API; specific manufacturer specifications may set tighter bounds for certain known degradants. Common related compounds and degradants observed by forced-degradation and synthetic route monitoring include des-trifluoromethoxy analogs, oxidative N-oxide species, hydroxy and deaminated benzothiazole derivatives, and residual starting materials such as 2-aminobenzothiazole; their acceptance criteria are established based on toxicological qualification and route knowledge. Residual solvents and elemental impurities are controlled per applicable ICH guidelines, for example residual solvents limited to the concentrations in ICH Q3C and elemental impurities to limits in ICH Q3D.
Riluzole is used to treat amyotrophic lateral sclerosis and other motor neuron diseases; it can slow disease progression for some patients by delaying respiratory failure and may extend survival by a few months.
Riluzole modulates glutamatergic neurotransmission through multiple actions including inhibition of presynaptic glutamate release, blockade of voltage-gated sodium channels that reduce excitatory neurotransmitter release, and indirect modulation of excitotoxic signaling pathways, which together reduce motor neuron excitotoxic stress.
Riluzole is classified as a neuroprotective agent with antiglutamatergic activity and is marketed as a prescription oral small-molecule medication for ALS and related motor neuron disorders.
Riluzole is used in ALS because reducing glutamate-mediated excitotoxicity and stabilizing neuronal electrical activity can slow motor neuron degeneration in some patients, translating into delayed respiratory compromise and a modest improvement in survival time.
