Detection and structure elucidation of the new degradation impurities in the pharmaceutical formulations of ruxolitinib hydrobromide

Physicochemical Stability Study of Oral Suspension Containing Ruxolitinib in Children with Steroid-Refractory Acute Graft-Versus-Host Disease

Ruxolitinib, used in children with steroid-refractory acute graft-versus-host (GVH) disease, is currently commercially available only as a tablet adult dosage. For the paediatric population, an oral liquid would be an adapted dosage formulation. The aim of this study was to develop ruxolitinib compounded oral suspensions at 2 mg/mL by using commercial tablets in available aqueous vehicle (Inorpha) and to measure its stability at both room temperature and under refrigeration. Chemical stability of suspensions containing ruxolitinib was evaluated for 60 days based on pH, degradation, and drug content. Physical stability of the drug suspension was evaluated by visual aspect and odour. The remaining ruxolitinib concentration of the suspension was at least 95% of the initial concentration after 60 days at both temperatures. The pH, colour, and odour of the suspensions throughout the study remained unchanged with respect to the initial time point.

Recent Progresses in Analytical Perspectives of Degradation Studies and Impurity Profiling in Pharmaceutical Developments: An Updated Review

Forced degradation studies have been used to simplify analytical methodology development and achieve a deeper knowledge about the inherent stability of active pharmaceutical ingredients (API) and drug products. This provides insight into degradation species and pathways. Identification of impurities in pharmaceutical products is closely related to the selection of the most appropriate analytical methods like HPLC-UV, LC-MS/MS, LC-NMR, GC-MS, and capillary electrophoresis. Herein, recent trends in analytical perspectives during 2018-April 14, 2021, are discussed based on forced and impurity degradation profiling of pharmaceuticals. Literature review showed that several methods have been used for experimental design and analysis conditions such as matrix type, column type, mobile phase, elution modes, detection wavelengths, and therapeutic category. Thus, since these factors influence the separation and identification of the impurities and degradation products, we attempted to perform a statistical analysis for the developed methods according to the abovementioned factors.

LC-HRMS studies on ruxolitinib degradation: a comprehensive approach during drug development

Ruxolitinib, a kinase inhibitor, was subjected to stress studies as described in the ICH Q1A(R2) guidelines. Solution state hydrolytic and solid state oxidative and thermal stress studies were carried out to understand its degradation behaviour. The drug showed significant instability in the hydrolytic condition in comparison with other conditions. HPLC and UHPLC methods were developed for the separation of the drug and its hydrolytic degradation products. Mass fragmentation pathway of the drug was established as the first step of the LC-MS characterization of the degradation products. MS/MS analysis of the drug and MS³ of selected fragments were achieved through QTOF and QTRAP by varying the collision energy and performing an H/D exchange. LC-MS/MS QTOF studies were subsequently carried out on stress samples and the structures of the degradation products were identified through comparison of the drug fragmentation pathways. The four hydrolytic products viz. 4-(1H-pyrazol-4-yl)-7H-pyrrolo[2,3-d]pyrimidine, 3-(4-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl)-3-cyclopentylpropanoic acid, 3-(4-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-1H-pyrazol-1-yl)-3-cyclopentylpropanamide, and 3-(4-(6-amino-5-formylpyrimidin-4-yl)-1H-pyrazol-1-yl)-3-cyclopentylpropanenitrile were formed under acidic and basic conditions. The degradation pathway was delineated through a mechanistic explanation. The in silico tools preADMET and Protox-II predictor were used to compare the toxicity of the impurities with respect to the drug.

Ruxolitinib photodegradation mechanisms by theoretical and experimental chemistry

Ruxolitinib is a Janus Kinase inhibitor currently approved for the treatment of myelofibrosis. It is also a promising drug for the treatment of skin and infectious diseases. In terms of pharmaceutical stability, although ruxolitinib has been established as being sensitive to light, no data on photodegradation processes are available to date, while these may be useful for quality risk management and any potential development of other pharmaceutical forms for other routes of administration. One way to partially fill this gap was to carry out a study that combines a consistent determination of the most sensitive sites of the molecule to photolysis through theoretical calculations based on functional density, with the identification of the main photodegradation products obtained after forced degradation. This integrated approach has shown converging results describing the mechanisms based on photo-oxidation that can lead to the opening of the pyrrole ring. Having access to the structure of the degradation products and intermediates then made it possible to carry out an in silico evaluation of their potential mutagenicity and it appears that some of them feature alert structures.