Varenicline is a synthetic pharmaceutical active ingredient used primarily in smoking-cessation medicines. It belongs to the class of nicotinic acetylcholine receptor ligands and acts as a partial agonist, particularly at the α4β2 nicotinic acetylcholine receptor subtype. Varenicline is commercially used predominantly in the form of varenicline tartrate, which provides the active varenicline moiety in pharmaceutical formulations.
Varenicline free base has the molecular formula C₁₃H₁₃N₃ and a molecular weight of approximately 211.26 g/mol. The commonly used pharmaceutical salt, varenicline tartrate, has the molecular formula C₁₇H₁₉N₃O₆, CAS Number 375815-87-5, and molecular weight approximately 361.35 g/mol.
Varenicline tartrate is described as a white to off-white or slightly yellow solid and is highly soluble in water in current pharmaceutical product information.
Varenicline is primarily used in pharmaceutical formulations intended to support smoking cessation. Its pharmacological action involves partial stimulation of α4β2 nicotinic acetylcholine receptors. By partially activating these receptors while also reducing the rewarding effects associated with nicotine, varenicline is used as an active pharmaceutical ingredient in smoking-cessation products.
The API is suitable for pharmaceutical development where controlled identity, assay, related substances, water content, residual solvents, and other critical quality attributes are required.
For pharmaceutical manufacturing, Varenicline Tartrate is the principal salt form encountered in approved oral varenicline products. Regulatory documentation identifies the active-substance specification as including appearance, IR and HPLC identification, assay, tartaric acid content, water content, residue on ignition, heavy metals, residual solvents, impurities, and particle-size controls.
Varenicline tartrate is supplied to pharmaceutical manufacturers and development organizations for use in formulations requiring a controlled and consistent source of API. Its quality characteristics can be evaluated through validated analytical procedures such as HPLC, IR, Karl Fischer water determination and chromatographic impurity testing.
Varenicline API requires careful control of related substances and process-related impurities. Published analytical research has identified multiple related substances associated with varenicline tartrate during development and stress studies.
Nitrosamine control is also an important consideration for varenicline because N-nitroso-varenicline has been subject to regulatory investigation. FDA has published analytical information concerning N-nitroso-varenicline testing in varenicline drug substances and drug products.
Varenicline API intended for pharmaceutical manufacturing should be sourced with appropriate documentation covering identity, assay, related substances, water, residual solvents and other applicable quality attributes. Manufacturers and buyers may require supporting documentation such as Certificate of Analysis, analytical specifications, batch information and regulatory documentation according to their intended market and application.
Swapnroop Drugs & Pharmaceuticals provides Varenicline API for pharmaceutical industry requirements, supporting manufacturers and organizations involved in pharmaceutical formulation and development.
| 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% |
| pH (1% Solution) | 3.78 |
| Melting Point | 195.8–197.5°C |