Bosentan Monohydrate Research Articles

Isolation, Identification, and Characterization of Forced Degradation Products of Bosentan by Using Advanced Analytical Techniques

ABSTRACTThe present study explains the degradation behavior of bosentan (BOS), active pharmaceutical ingredient (API) (BOS monohydrate), a Food and Drug Administration (FDA)–approved drug used for the treatment of chronic heart failure, subarachnoid hemorrhage, and Raynaud's syndrome pulmonary hypertension. The stress study was performed under various stress conditions such as acid hydrolysis, base hydrolysis, oxidation, thermal degradation, and photolysis as per International Council for Harmonization (ICH) guidelines and found three degradation products (DPs) under acid hydrolysis conditions (1 N HCl/4 h/60°C reflux conditions) (the net degradation of API ∼ 21.39%). The drug was found to be stable under the remaining conditions (thermal, photolytic, oxidative, and basic hydrolytic conditions). Mechanisms for forming the three acid DPs were also proposed and discussed. The DPs were initially detected by ultrahigh‐performance liquid chromatography–mass spectrometry analysis. These DPs were isolated by preparative HPLC and then characterized by high‐resolution mass spectrometry and nuclear magnetic resonance spectroscopy techniques. Based on the structural characterization study, all these DPs are new and not reported elsewhere in the literature to my knowledge. Many reports were found in the literature for the quantification of the drug in the APIs and formulation products. However, there is no report published yet for the identification and characterization of DPs of the BOS drug.

Bosentan monohydrate and sildenafil base as two companions in enabling formulations

Hypothesis: Sildenafil base and bosentan monohydrate are co-administered in a chronic therapy of pulmonary arterial hypertension (PAH). Both drugs are poorly soluble in water, and their bioavailability is limited to ca. 50 %. Since bosentan is a weak acid, whereas sildenafil is a weak base, we assumed that their co-amorphization could: (i) improve their solubility in the gastrointestinal fluids, (ii) enable to reach supersaturation and (iii) ensure stabilization of supersaturated solutions. If successful, this could accelerate the development of new fixed-dose combination drugs. Experiments: The co-amorphous formulations were prepared using high energy ball milling. Their solid state properties were assessed using XRD, DSC, FT-MIR, and dielectric spectroscopy. Particle size distribution and surface wetting were also analyzed. Polarizing optical microscopy and scanning electron microscopy were applied to assess the microstructure of these powders. A new HPLC-DAD method was developed for a simultaneous quantification of both drugs. Findings: It was shown that binary formulations in which bosentan was molecularly dispersed in sildenafil base (Tg = 64-78 °C) could be manufactured in the high energy ball milling process. When the sildenafil load was below 50 wt. %, the formulations showed the greatest thermal stability and formed long-lasting bosentan supersaturation in PBS.

Formulation, Development, and Evaluation of Bosentan Monohydrate Spray Dried- Solid Dispersion Tablets for Improved Dissolution Profile

Bosentan monohydrate (BM) is utilized for the treatment of pulmonary arterial hypertension, exhibiting poor aqueous solubility and bioavailability. This study aims to enhance the dissolution rate of the drug using Eudragit®EPO through spray drying. The drug and Eudragit®EPO were combined in ratios of 1:1, 1:2, 1:3, 1:4, and 1:5 (w/w) to generate compositions SD1 to SD5. SD5, at a 1:5 drug-to-carrier ratio, demonstrated a statistically significant increase in saturation solubility and drug content. Six tablet formulations (F1 to F6) containing SD5 and tableting excipients were developed and processed. Formulation F2, consisting of 26.36% HPMC K4M and 23.63% MCC, exhibited the highest dissolution and drug release. The probable mechanism underlying BM dissolution in SD involves its amorphous form and the solubilizing effect facilitated by hydrogen bonding between BM and Eudragit®EPO. The carrier's binding effect likely contributed to high tensile strength, low friability, and extended disintegration time. Direct mixing of SD with HPMC might have improved the uniformity of SD within the tablet matrix and the release profile. This study demonstrates the efficacy of spray drying in preparing SD of BM with Eudragit®EPO, potentially enhancing its solubility and stability.

Molecular phenomena related to moisture uptake in amorphous solid dispersion loaded with bosentan monohydrate and copovidone

Amorphous bosentan alone lacks dissolution flux that could enhance its bioavailability. Its coamorphization with hydrophilic copovidone (1:1) enables to improve wettability and dissolution rate, but fine amorphous particles are prone to moisture uptake. Water sorbed on the surface of this amorphous solid dispersion can considerably alter its physical properties annihilating benefits of coamorphization. The gravimetric measurements of water uptake, the solid state 1H NMR spectroscopy and relaxometry enabled us to describe for the first time, phase changes initiated by hydration in amorphous bosentan systems. The properties of copovidone greatly impacted water uptake in bosentan solid dispersions. A nonlinear reduction of the Tg upon water sorption resulted in the transformation of the glassy state into the rubbery state at ambient temperature. The state diagrams were developed for optimization of manufacturing conditions, selection of suitable packaging material and storage temperature, ensuring long-term stability of amorphous bosentan products.

Development and Characterization of Bosentan Monohydrate-loaded Self-Nano Emulsifying Drug Delivery System

Aim/ Objective: The present investigation aims to develop a solid Self-nano emulsifying Drug Delivery System for enhancing the solubility and in vitro characteristics of poorly soluble an-ti-hypertensive drug Bosentan Monohydrate. Methods: The selection of formulation components on the basis of equilibrium solubility and pseu-do-ternary phase titration studies revealed the suitability of Isopropyl myristate, Tween 80 and Pol-yethylene glycol as the lipidic excipients and their optimized concentration ranges resulted in a sta-ble microemulsion region. Results: The systematic optimization of the liquid SNEDD formulations of Bosentan was per-formed using in vitro tests and detailed characterization studies. The results revealed that the F4 formulation produces excellent results and satisfactory results in all the CQA of liquid SNEDDS. The optimized liquid SNEDD formulations exhibited globule size of less than 100 nm, high and negative values of zeta potential, quick self-emulsification rate, negligible phase separation, and a high degree of physical stability during thermodynamic evaluation studies. SEM revealed nanostructured particles with negligible aggregation. Conclusion: In vitro dissolution studies of Bosentan in optimized liquid SNEDDS (F4) unveiled a multi-fold enhancement in release profile, as compared to pure API.

Formulation and optimization of polymeric agglomerates of Bosentan monohydrate by crystallo-co-agglomeration technique

BackgroundThe polymeric spherical agglomerate of Bosentan monohydrate was prepared by crystallo-co-agglomeration technique, for enhancing the micrometric properties and solubility of the drug. The agglomerates were developed using two distinct solvents, DCM as a good solvent and bridging liquid and water as a weak solvent, respectively. Hydrophilic polymer like HPMC K100M is used as a hardening agent which gives mechanical strength to the agglomerates, and PEG6000 is used as a wetting agent. Other excipients like talc which was used as a size enhancer, and PVA was used as an emulsifier agent. The formulation was optimized by Box–Behnken design. The concentration of talc and PEG6000, as well as rotation speed, was considered as independent variables. The particle size, angle of repose, and % drug content were used as dependent variables to investigate the effect of independent variables on dependent variables. The spherical crystal agglomerates were subjected to various physicochemical evaluations.ResultsThe results revealed that as the concentration of talc and PEG6000 increases, the sphericity and particle size of the agglomerates increase, and at a low agitation, speed agglomerates become more spherical and coarser, which is confirmed by FESEM. The characterization like FTIR confirms no interaction with excipients, while XRPD confirms the polymorphic changes, and gas chromatography (GC) confirms the concentration of residual organic solvents in PDE limits. The optimized formulation of SAs showed a good angle of repose which is 30.33 ± 0.35, and the % cumulative drug release at 20 min was 94.14 ± 0.628%. Finally, the FDTs of the optimized batch were prepared.ConclusionsThe comparison of the in vitro release study of pure drugs with agglomerates and fast dispersible tablets of agglomerates confirms the solubility improvement. Finally, it can be concluded that the polymorphic crystal agglomerates enhance the solubility and micrometric properties of Bosentan monohydrate.

Human medicines European public assessment report (EPAR): Stayveer, bosentan monohydrate, Hypertension, Pulmonary,Scleroderma, Systemic, Date of authorisation: 24/06/2013, Revision: 9, Status: Authorised

Human medicines European public assessment report (EPAR): Stayveer, bosentan monohydrate, Hypertension, Pulmonary,Scleroderma, Systemic, Date of authorisation: 24/06/2013, Revision: 9, Status: Authorised

Novel propyl karaya gum nanogels for bosentan: In vitro and in vivo drug delivery performance

The amphiphilic propyl Karaya gum (KG) with a degree of propyl group substitution of 3.24 was synthesized to design self-assembled nanogels as carriers for bosentan monohydrate, a poorly soluble antihypertensive drug. The drug was physically hosted into the hydrophobic core of the micellar nanogels by solvent evaporation method. TEM images revealed spherical shape and core-shell morphology of the nanogels. Depending upon polymer: drug weight ratio, the drug entrapment efficiency of >85% was attained. The carriers had hydrodynamic diameter in the range of 230–305 nm with narrow size distribution. The zeta potential of −23.0 to −24.9 mV and low critical association concentration (CAC) of 8.32 mg/l provided evidence that the colloidal nanogel system was physically stable. Thermodynamics of the propyl KG system in water favored spontaneous self-assembly of propyl KG. FTIR, thermal and x-ray analyses suggested that the drug was compatible in the hydrophobic confines of the nanogels. The micellar nanogels liberated their contents in simulated gastrointestinal condition in a pH-dependent manner over a period of 10 h. Peppas-Sahlin modeling of in vitro drug release data suggested that the polymer relaxation/swelling mechanism dominated the drug release process. Pre-clinical testing of the mucoadhesive nanogel formulations exhibited that the system could monitor the anti-hypertensive activity for a prolonged period. Overall, this propyl KG micellar nanogel system had a great potential and splendid outlook to serve as novel oral controlled release carriers for poorly soluble drugs with outstanding pharmacodynamics.

DESIGN DEVELOPMENT AND OPTIMIZATION OF A SUSTAINED RELEASE TABLET OF BOSENTAN MONOHYDRATE FOR PULMONARY ARTERIAL HYPERTENSION

Pulmonary arterial hypertension (PAH) means high blood pressure in the lungs caused by obstruction in the small arteries of the lungs.The current study involves the fabrication of oral matrix sustained release tablet of bosentan monohydrate, a dual endothelin receptor antagonist, the optimisation of its in vitro release and characterisation. Methocel K4M PremiumDC2, a directly compressible HPMC grade, has been used as the sustained release polymer. Pregelatinised starch is used as a diluent and release modifier and sodium lauryl sulphate as a solubiliser. The influence of the above variables on drug release is measured using a 23 factorial design using design expert software. Surface response plots show significant interaction among the formulation variables, thus aiding in optimization of bilayer tablet.

FORMULATION DEVELOPMENT AND STATISTICAL OPTIMIZATION OF A BILAYER TABLET OF BOSENTAN MONOHYDRATE AND SILDENAFIL CITRATE IN MANAGEMENT OF PULMONARY ARTERIAL HYPERTENSION

Objective: The current study aims at fabrication of an oral bilayer matrix tablet of bosentan monohydrate and sildenafil citrate; the optimisation of their in vitro release and characterization, thereby reducing the side effects associated with bosentan, reducing dosing frequency and increasing patient compliance in the management of pulmonary arterial hypertension.
 Methods: Methocel K4M Premium DC2, a directly compressible HPMC grade was used as the sustained release polymer. Pregelatinised starch is used as a diluent and release modifier and sodium lauryl sulphate (SLS) as a solubiliser. The blends of both layers were prepared, evaluated for precompression characteristics and compressed by direct compression. The compressed bilayer tablets were evaluated for their hardness, weight variation, friability, content uniformity and swelling index. The principle objective was to assess the influence of the above variables on in vitro drug release of Bosentan using a 23 factorial design. Responses are measured as drug release at 2h (Q2), 6h (Q6) and 10h (Q10).
 Results: HPMC and pregelatinized starch form a synergistic gel thereby controlling drug release of bosentan for a 12 hour period. Batch BS09 consisting of 40 mg HPMC, 30 mg Pregeletinized starch and 5 mg SLS showed adequate controlled release for a 12 h period. Immediate release layer of sildenafil citrate showed optimum drug release of 102.96% within 30 min.
 Conclusion: Bilayer tablet of bosentan and sildenafil is an ideal combination for patients failing monotherapy in pulmonary arterial hypertension.

PHARMACOKINETIC STUDY OF MATRIX MEMBRANE MODERATED TRANSDERMAL SYSTEM OF BOSENTAN MONOHYDRATE

Objective: The objective of the present research work is to carry out the pharmacokinetic studies of optimized matrix membrane moderatedtransdermal patch of bosentan monohydrate.Materials and Methods: The matrix membrane moderated transdermal system was formulated using HPMC, HPMC K4M and E RLPO. In vitrodiffusion studies were carried out using modified Franz diffusion cell and for the optimized transdermal patch, pharmacokinetic studies were carriedout using New Zealand male rabbits. Plasma samples were quantified using high-performance liquid chromatography.Results: The in vitro diffusion studies revealed that formulation F3 with HPMC K4M and E RLPO had controlled release up to 28 hrs, and a maximumof 95.02±2.68% drug was released. The release kinetics followed mixed order non-Fickian diffusion. The pharmacokinetic studies of the optimizedpatch revealed controlled release up to 45 hrs where a 2.2-fold increase in area under curve (AUC) and 3.8 times increase in mean residence time(MRT) were observed compared to oral route. The results were appeared to be significant at p≤0.05. The variation in half-life was found to be notstatistically significant when compared between oral and transdermal routes.Conclusion: The pharmacokinetic results concluded that the matrix membrane moderated transdermal system with extended AUC and MRT canenhance the bioavailability of bosentan monohydrate by minimizing the drug-related side effects in oral route.

Improvement in Dissolution of Bosentan Monohydrate by Solid Dispersions Using Spray Drying Technique

Background: Bosentan monohydrate (BM), a dual endothelin receptor antagonist, is indicated for the treatment of patients with pulmonary arterial hypertension (PAH). It is poorly soluble in water, and having absolute bioavailability of 50%. Objective: The aim of the present work is to develop and evaluate the solid dispersions (SD) of a poorly water soluble drug bosentan monohydrate (BM). Method: Solid dispersions (SDs) systems of BM were prepared with Hydroxy propyle β-cyclodextrin (HPβ-CD) and Polyethylene glycol (PEG-4000) polymers using a spray drying technique. Result: The significant rise in a saturation solubility 174.23±1.36 mg/mL; and drug dissolution 95.11±1.22%; was observed with optimized formulation (SD 6). The solid state characterization of optimized formulation (SD 6) by SEM, DSC, and XRPD revealed the absence of crystalline nature of BM in solid dispersion. High dissolution rate of solid dispersion (SD 6) compared with pure drug indicated the increase in dissolution characteristics. Conclusion: In conclusion, our studies illustrated that spray drying technique could be useful large scale producing method to prepare the solid dispersion of bosentan with HP β-CD, which can improve the solubility as well as stability of the formulation.

Bosentan Monohydrate Vesicles Loaded Transdermal Drug Delivery System: In Vitro In Vivo Evaluation

This study elucidates the enhancement of the permeation of bosentan monohydrate through skin by encapsulating it in vesicles loaded transdermal delivery system. Niosomal vesicles were formulated by ether injection method. Formulation FN7 (span 60: cholesterol: poloxamer 401, 1.25:1:0.25) showed maximum entrapment efficiency of 96.7±0.037% and was optimized for loading in to transdermal system. Transdermal systems were formulated using both hydrophilic and hydrophobic polymers like HPMC, HEC and EC. Formulation F1 with HPMC was optimized based on in vitro release (99.21±1.45 %) and was further evaluated for ex-vivo permeation. The results indicate that the ex vivo release (98.13±1.65%) was as par with in vitro release and followed zero order super case- II transport mechanism. The in vivo studies were done on New Zealand male rabbits for oral and transdermal route. The results inferred no significant change in half-life of drug but a substantial difference in Tmax, AUC and MRT was observed in transdermal systems. A two fold increase in AUC was observed in transdermal route (18.609±7.251µg/ml/h) when compared to oral route (9.644±5.621µg/ml/h). A controlled release was attained up to 35h and reservoir effect was observed and this may be due to the barrier properties of skin. Drug encapsulated niosomes were released in to the skin by loosening the lipid layers and the surfactant acted as penetration enhancer. The study infers that niosomes loaded transdermal patches of bosentan monohydrate can enhance the bioavailability and provided controlled release for better therapeutic efficacy and safety of drug.

A Study on the Effect of disintegrants and Processing Methods on the Physicochemical and In Vitro Release Characteristics of Immediate Release Tablets of Bosentan Monohydrate

A Study on the Effect of disintegrants and Processing Methods on the Physicochemical and <i>In Vitro</i> Release Characteristics of Immediate Release Tablets of Bosentan Monohydrate

Estimation of Bosentan Monohydrate in Male Rabbit Plasma by using RP-HPLC Method

Simultaneous estimation of lidocaine and prilocaine in topical cream by green gas chromatographyHashim Chekku Marakkarakath, Gurupadayya Bannimath, Prachi Pramesh Raikar

Improved Large-Scale Synthesis of Bosentan Monohydrate

Bosentan is a non-peptidic endothelin receptor antagonist used for the treatment of pulmonary artery hypertension (PAH), congestive heart failure and cardiovascular pathology.1,2 Bosentan monohydra...

Development and Validation of a UHPLC UV Method for the In-Process Control of Bosentan Monohydrate Synthesis.

Bosentan monohydrate (4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl) pyrimidin-4-yl]benzene-1-sulfonamide monohydrate) is a dual endothelin receptor antagonist (ERA) applied in the treatment of pulmonary arterial hypertension. To achieve effective process control of the bosentan monohydrate synthesis, it was necessary to develop a selective and not highly time-consuming method for ultra-high performance liquid chromatography (UHPLC). The method is characterized by adequate sensitivity, reproducibility and selectivity for the determination of bosentan monohydrate and related compounds from all synthetic stages. The UHPLC separation was carried out by reversed phase chromatography on the Acquity BEH C18 column (100 mm × 2.1 mm, 1.7 µm) with a mobile phase composed of solvent A (0.1 %, v/v, acetic acid in water) and solvent B (methanol), in the gradient mode at the flow rate of 0.4 mL min−1. Limits of detection and quantification for the compounds were ≤0.1 µg mL−1 and 0.3 µg mL−1, respectively. The linearity for all related compounds was investigated as in the range for the active pharmaceutical ingredient (API) and as in the range for the in-process control. The developed method was validated according to the current guidelines, proving the suitability of the method for its intended purpose.

Stability of an Extemporaneously Compounded Oral Suspension of Bosentan

To assess the stability of an extemporaneously compounded oral suspension of bosentan from commercially available tablets for a period of 1 month. A 6.25 mg/mL oral suspension of bosentan monohydrate was prepared from Tracleer tablets. The bosentan suspension was then evenly divided between 2 light-resistant prescription bottles and stored in the dark either under refrigeration (4-8°C) or at controlled room temperature (21-26°C). The suspensions were assessed for physical changes (ease of resuspendability, change in color, change in odor), and samples were drawn immediately after preparation and on days 0, 1, 3, 7, 10, 14, 21, 28, and 31. Samples were analyzed at each time point by high-performance liquid chromatography (HPLC) utilizing a reversed-phase column with chemical stability defined as the retention of at least 90% of the initial intact bosentan concentration measured. No change in suspendability, color, or odor of the compounded bosentan suspensions was noted throughout the storage period. Furthermore, regardless of storage conditions, the oral suspension of bosentan retained at least 94% of the active pharmaceutical ingredient for 31 days after preparation. The results of our study indicate that a 6.25 mg/mL bosentan oral suspension stored in the dark under refrigeration and at room temperature maintains physical and chemical stability for 1 month.

PSY47 - Patient-Reported Outcome (Pro) Claims In Products Indicated For The Treatment Of Rare Diseases And Approved By The European Medicines Agency (Ema)

different therapeutic areas (classified according to the ICD-10; see Table 1) and 67 different indications. The most represented therapeutic areas were neoplasms (28 products, 40.6%) and endocrine, nutritional and metabolic diseases (21 products, 30.4%).  Out of the 69 products, 14 had a PRO claim (20.3%); see Table 2. By comparison, a review performed in 2011 [1] showed that 22% of all EMA products approved between 2005 and 2010 had a PRO claim in their labeling (in particular in the 5.1. section of the approved labeling). PROs identified in the claims were assessing function [e.g., physical functioning ; 2 products (14.29%)], symptoms [e.g., pain; 12 products (85.71%)] and quality of life [(QOL) – 4 products (28.6%)]; with some products cumulating different types of claims. Corresponding therapeutic areas and indications were neoplasms (trabectedin, ofatumumab, ruxolitinib), endocrine diseases (aztreonam lysine, ivacaftor, tafamidis), nervous system diseases (stiripentol, rufinamide), blood diseases (eculizumab, icatibant), pulmonary arterial hypertension (bosentan monohydrate, ambrisentan), cryopyrin-associated periodic syndromes (rilonacept), and severe pain (ziconotide).  More than one product out of four (4/14) had a QOL claim: two for neoplasms [trabectedin (ovarian cancer) – no differences between treatment in QOL; and ruxolitinib (myeolofibrosis) improvement of QOL], one in diseases of the blood [eculizumab (two indications: paroxysmal nocturnal haemoglobinuria and atypical haemolytic uraemic syndrome improvement of QOL], one in endocrine disease [tafadimis (amyloidosis) – improvement of QOL]. Patient-reported outcome (PRO) claims in products indicated for the treatment of rare diseases and approved by the European Medicines Agency (EMA) Benoit Arnould*1, Laure-Lou Perrier2, Catherine Acquadro2 1Mapi, HEOR and Strategic Market Access, Lyon, France; 2Mapi Research Trust, Lyon, France

An Alternate Synthesis of Bosentan Monohydrate, an Endothelin Receptor Antagonist

An alternate synthesis of an endothelin receptor antagonist bosentan monohydrate is reported. This new synthetic route involves the coupling of p - tert -butyl- N -[6-chloro-5-(2-methoxy-phenoxy)(2,2′-bipyrimidin)-4-yl]benzene sulfonamide with commercially available raw material (2,2-dimethyl-1,3-dioxolan-4-yl)methanol as the key step. Attractive features of this approach are its versatileness, commercial availability of raw materials, usage of eco-friendly reagents, and it efficiently provides the desired bosentan monohydrate free from reported impurities such as dimer, N-alkylated, and pyrimidinone impurities.