Dear Esteem Community Members,
May anyone assist or share publication and or protocol outline for an In Vitro Metabolism Study with Human hepatocytes or microsome to study metabolites generate by NDSRI ?
Any assistance ob this matter is appreciate!
Thanking you in anticipation.
Regards
This study, published by Cheung et al., might give you a good reference as a starting point.
Evaluation of the nitrosamine impurities of ACE inhibitors using computational, in vitro, and in vivo methods demonstrate no genotoxic potential
https://onlinelibrary.wiley.com/doi/10.1002/em.22618
Abstract:
Evaluation and mitigation of the potential carcinogenic risks associated with nitrosamines in marketed pharmaceutical products are areas of interest for pharmaceutical companies and health authorities alike. Significant progress has been made to establish acceptable intake (AI) levels for N -nitrosamine drug substance-related impurities (NDSRIs) using SAR, however some compounds require experimental data to support derivation of a recommended AI. Many angiotensin-converting enzyme inhibitors, identified by the suffix “pril,” have secondary amines that can potentially react to form nitrosamines. Here we consider a structural assessment and metabolism data, coupled with comprehensive in vitro and in vivo (mouse) genotoxicity testing to evaluate this particular class of nitrosamines. N -nitroso ramipril and N -nitroso quinapril, both of which are predicted to have inhibited nitrosamine bioactivation due to steric hinderance and branching at the α-position were non-genotoxic in the in vivo liver comet assay and non-mutagenic in the in vivo Big Blue® mutation and duplex sequencing assays. Predicted metabolism along with in vitro metabolism data and quantum chemical calculations related to DNA interactions offer a molecular basis for the negative results observed in both in vitro and in vivo testing. These nitrosamines are concluded to be non-mutagenic and non-carcinogenic; therefore, they should be controlled according to ICH Q3B guidance. Furthermore, these results for N -nitroso ramipril and N -nitroso quinapril should be considered when evaluating the appropriate AI and control strategy for other structurally similar “pril” NDSRIs.
The USFDA has specifically cited this article on their website ( CDER Nitrosamine Impurity Acceptable Intake Limits | FDA ) for the human in vitro assays:
Li X, et al. Revisiting the mutagenicity and genotoxicity of N-nitroso propranolol in bacterial and human in vitro assays. Regul Toxicol Pharmacol. 2023 Jun; 141:105410
doi:10.1016/j.yrtph.2023.105410
The following article is also available in the public domain,
Mutagenicity and genotoxicity evaluation of 15 nitrosamine drug substance-related impurities in human TK6 cells, 10.1016/j.yrtph.2024.105730
Both these articles have been published by USFDA and are free to download; they should serve as a basis for performing in vitro studies using human tissues.
Thank you for sharing valuable information!