Separation, identification and characterization of stress degradation products of bortezomib using HPLC and LC-MS.

Bortezomib (BT) is a reversible inhibitor of proteasome which is used in the treatment of hematological cancers. To study the degradation behavior, BT was subjected to acidic, basic, neutral, photolytic, oxidative and thermal degradation conditions as per ICH guideline Q1A (R2). A gradient HPLC method has been developed for separating all the degradation products formed under various degradation conditions on Waters XBridge C₁₈ column (150 mm × 4.6 mm × 3.5 µm) using the mobile phase composed of ammonium formate and acetonitrile. A total of six degradation products were formed in various stress conditions and these were separated identified, and characterized using high performance liquid chromatography in combination with electrospray ionization tandem mass spectrometric studies.