The Landscape of Potential Small and Drug Substance Related Nitrosamines in Pharmaceuticals.

This article reports the outcome of an in silico analysis of more than 12,000 small molecule drugs and drug impurities, identifying the nitrosatable structures, assessing their potential to form nitrosamines under relevant conditions and the challenges to determine compound-specific AIs based on data available or read-across approaches for these nitrosamines and their acceptance by health authorities. Our data indicate that the presence of nitrosamines in pharmaceuticals is likely more prevalent than originally expected. In total, 40.4 % of the analyzed APIs and 29.6 % of the API impurities are potential nitrosamine precursors. Most structures identified through our workflow could form complex API-related nitrosamines, so-called nitrosamine drug substance related impurities (NDSRIs), although we also found structures that could release the well-known small and potent nitrosamines NDMA, NDEA, and others. Due to common structural motifs including secondary or tertiary amine moieties, whole essential drug classes such as beta blockers and ACE inhibitors are at risk. To avoid the risk of drug shortages or even the complete loss of therapeutic options, it will be essential that the well-established ICH M7 principles remain applicable for nitrosamines and that that the industry and regulatory authorities keep an open communication not only about the science but also to make sure there is a good balance between risk and benefit to patients.

A GC-MS/MS Method for Trace Level Quantification of Six Nitrosamine Impurities (NDMA, NDEA, NEIPA, NDIPA, NDPA, and NDBA) in Commercially Used Organic Solvents: Dichloromethane, Ethyl Acetate, Toluene, and O-xylene.

Nitrosamines, the probable carcinogens have been reported with Angiotensin II Receptor Blocker (ARB) drugs, Ranitidine, and other medicines. Solvents play a vital role in the pharmaceutical industry in the separation, purification, and cleaning process for manufacturing APIs and drug products. According to the FDA and EMA, solvents used in the drug manufacturing process are potential root causes of Nitrosamine impurities. Hence, monitoring nitrosamines in solvents is an essential step for manufacturers. A sensitive direct injection GC-MS/MS, an essential analytical tool for low-level nitrosamine quantification in solvents, was developed by utilizing multiple reactions monitoring mode (MRM) for the simultaneous determination of six nitrosamines, namely, NDMA, NDEA, NEIPA, NDIPA, NDPA and NDBA in common solvents such as dichloromethane, ethyl acetate, toluene, and o-xylene. NDMA-d6 was used as an internal standard. The FDA reported a combined direct injection method for nitrosamine impurity assay by GC-MS/MS, which had several challenges for commercial-grade solvents in terms of interferences and resolution of unknown impurities and nitrosamine peaks. A novel method was developed to optimize the critical parameters of GC-MS/MS according to the solvent samples. The method validation was performed through the following parameters, sensitivity, linearity, accuracy, precision, specificity, and stability. The quantification of nitrosamines in commercial-grade solvents ranged from 100 ppb to 8000 ppb with respect to the sample concentration of 25 mg/mL with good sensitivity in LOQ level. The quantification ranged from 5 ppb (for NDMA, NDEA, NEIPA, NDIPA, NDPA) and 13 ppb (NDBA) to 2000 ppb with respect to the sample concentration of 100 mg/mL for analytical grade solvents with good sensitivity in the proposed method. Hence, it will be useful to quantify the low-level nitrosamines in commercial-grade solvents as well as analytical-grade solvents.

Isolation and characterization of novel degradation products of Doxofylline using HPLC, FTIR, LCMS and NMR.

Forced degradation of Doxofylline (DFL) in different stress (base and peroxide) conditions gave rise to two potential unknown impurities. These unknown degradation products DFL DEG-I and DFL DEG-II were evaluated using a new-reverse-phase high performance liquid chromatography (HPLC), where it was eluted at 0.44 and 1.09 relative retention times to DFL peak. DFL DEG-I and DFL DEG-II were isolated using preparative HPLC from degradation mixtures. The structure of DFL DEG-I and DFL DEG-II were elucidated using high resolution MS, multi-dimensional NMR and FTIR spectroscopic techniques, and characterized. The stereochemistry of the enantiomers in DFL DEG-II has further been investigated using computational techniques. To the best of our knowledge, DFL DEG-I and DFL DEG-II are novel impurities and not reported elsewhere.

Isolation and structural characterization of novel photolytic degradation impurities of Deflazacort using Q-TOF, 2D-NMR and FTIR.

Forced Degradation of Deflazacort drug substance in ultraviolet light condition resulted into a number of significant degradation products. Two of these degradation products were found to be unknown during the study and marked as DD-I and DD-II. Thus, the objective of this work is to investigate and identify these two novel degradation products of DFZ. The isolation method for these new degradation products were developed using a new reverse-phase high performance liquid chromatography (HPLC). DD-I and DD-II, eluting at 0.53 and 1.57 relative retention times with respect to Deflazacort (DFZ) peak respectively, were isolated from reaction mass using preparative HPLC and their structures were elucidated using high resolution MS, multidimensional NMR and FTIR spectroscopic techniques. To best of our knowledge, these two degradation products are novel impurities which are not discussed in any form of publication yet.