Yerra Naga Veera, Pallerla Pavankumar, Pandeti Sukanya, Tabet Jean-Claude, Thota Jagadeshwar Reddy
Analytical Chemistry and Mass Spectrometry, CSIR-Indian Institute of Chemical Technology, Hyderabad, - 500 007, India.
Academy of Scientific and Innovative Research, New Delhi, - 110001, India.
Rapid Commun Mass Spectrom. 2018 Jul 15;32(13):1075-1084. doi: 10.1002/rcm.8138. Epub 2018 May 27.
Stress testing of a drug candidate is an important step in the drug discovery and development process. The presence of degradation products in a drug affects the quality as well as the safety and efficacy of drug formulation. Hence, it is essential to develop an efficient analytical method which could be useful for the separation, identification and characterization of all possible degradation products (DPs) of a drug. Macitentan (MT) is an endothelin receptor antagonist (ERA) drug used to treat high blood pressure in the lungs. Comprehensive stress testing of MT was carried out as per ICH guidelines to understand the degradation profile of the drug.
MT was subjected to various stress conditions such as acidic, basic, neutral hydrolysis, oxidation, photolysis and thermal conditions; and the resulting degradation products were investigated using liquid chromatography/diode-array detection/electrospray ionization high-resolution mass spectrometry (LC/DAD/ESI-HRMS) and tandem mass spectrometry (MS/MS) techniques. An efficient and simple ultra-high-performance liquid chromatography (UHPLC) method has been developed using an Accucore C18 column (4.6 × 150 mm, 2.6 μm) using a gradient elution of 5 mM ammonium formate and acetonitrile as mobile phases.
MT was found to degrade under acid and base hydrolysis stress conditions; whereas it was stable under oxidation, neutral hydrolysis, thermal and photolytic conditions. MT formed nine DPs (DP1 to DP9) and one DP (DP10) under acidic and basic hydrolytic conditions, respectively. All the degradation products (DP1 to DP10) were identified and characterized by LC/MS/MS in positive ion mode with accurate mass measurements.
MT was found to be labile under hydrolytic conditions. The structures of the DPs were characterized by appropriate mechanisms. The proposed method can be effectively used for the characterization of MT and its DPs.
对候选药物进行稳定性研究是药物发现和开发过程中的重要一步。药物中降解产物的存在会影响药物制剂的质量以及安全性和有效性。因此，开发一种高效的分析方法对于分离、鉴定和表征药物所有可能的降解产物至关重要。马昔腾坦（MT）是一种内皮素受体拮抗剂（ERA）药物，用于治疗肺动脉高压。按照国际人用药品注册技术协调会（ICH）指南对MT进行了全面的稳定性研究，以了解该药物的降解情况。
MT分别置于各种应激条件下，如酸性、碱性、中性水解、氧化、光解和热条件下；并使用液相色谱/二极管阵列检测/电喷雾电离高分辨率质谱（LC/DAD/ESI-HRMS）和串联质谱（MS/MS）技术研究所得的降解产物。采用Accucore C18柱（4.6×150 mm，2.6μm），以5 mM甲酸铵和乙腈为流动相进行梯度洗脱，开发了一种高效且简便的超高效液相色谱（UHPLC）方法。
发现MT在酸和碱水解应激条件下降解；而在氧化、中性水解、热和光解条件下稳定。MT在酸性和碱性水解条件下分别形成9种降解产物（DP1至DP9）和1种降解产物（DP10）。所有降解产物（DP1至DP10）均通过LC/MS/MS在正离子模式下进行了鉴定和表征，并进行了精确质量测定。
发现MT在水解条件下不稳定。通过适当的机制对降解产物的结构进行了表征。所提出的方法可有效地用于MT及其降解产物的表征。
