Forced degradation studies provide rapid access to degradation products (DPs), where structural characterization and assessment of their potential toxicity are vital for pharmaceutical safety and regulatory compliance. As per the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) Q1A R(2) guidelines, a forced degradation study of Bictegravir (BIC), a USFDA-approved drug for HIV wild type, in hydrolytic conditions (acid, base, and neutral) revealed the formation of six DPs in RP-HPLC (Reverse Phase- High-Performance Liquid Chromatography) gradient elution program using a C18 (4.6 × 250 mm, 5 µm) column. DP-1, 2, and 3 were characterized using liquid chromatography-tandem mass spectrometry (LC-MS/MS), whereas DP-4, 5, and 6 posed difficulties in characterization due to their isomeric nature. Using characteristic NOEs (Nuclear Overhauser Effect) from 2D ROESY NMR (Nuclear Magnetic Resonance) studies, we have elucidated diastereomeric DP-4/5 and isomeric DP-6/BIC configurational structures. Furthermore, in silico toxicity studies for the six degradation products were predicted for toxicity endpoints by employing DEREK, SARAH, and Pro Tox-II application tools. The DP-1 (methanamine) and DP-3 (carboxylic acid) resulting from acid-catalyzed hydrolysis, were predicted to have potential carcinogenic and mutagenic properties. These findings contribute significantly to our understanding of BIC’s stability and safety profile in pharmaceutical development and underscore the rigorous characterization of stereoisomers by NMR that were further utilized for toxicity prediction.Copyright © 2023 Elsevier B.V. All rights reserved.
