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Background: Access to inhaled nitric oxide (iNO) is limited in low resource settings due to non-availability and high cost. There is a need for research on low-cost alternative therapies for management of persistent pulmonary hypertension of the newborn (PPHN). We aimed to compare oral sildenafil and bosentan as monotherapy in the treatment of neonates with PPHN. Study design: In this single-centre open-label randomized controlled trial (RCT), term and late preterm neonates with PPHN, defined as pulmonary arterial systolic pressure (PASP) > 35 mmHg and requiring fraction of inspired oxygen (FiO2) > 0.21, were randomized to receive oral sildenafil and bosentan. The primary outcome was reduction of PASP by 25% within 48 h after start of drug. Results: Thirty-six neonates were analyzed (18 in each group). Initial PASPs were similar in both groups. The median (IQR) time for the primary outcome (PASP to reduce by 25% within 48 h) was 36 (24–48) h and 96 (48–120) h in sildenafil and bosentan groups respectively (p = 0.008). There was also a higher need to add other pulmonary vasodilators in bosentan group as compared to sildenafil group (p = 0.006). Conclusion: Sildenafil was associated with quicker reduction of PASP and FiO2 in neonates with PPHN, as compared to bosentan. Large multicentre blinded trials to assess efficacy and safety of bosentan in comparison with other pulmonary vasodilators would help to get a clearer understanding of its role in the management of PPHN, particularly for use in resource-limited settings that lack iNO. Clinical trial registration: https://ctri.nic.in/Clinicaltrials/rmaindet.php? trialid=63997&EncHid=39716.16132&modid=1&compid=19[CTRI/2022/06/043328]. [ABSTRACT FROM AUTHOR]

Abstract Background Access to inhaled nitric oxide (iNO) is limited in low resource settings due to non-availability and high cost. There is a need for research on low-cost alternative therapies for management of persistent pulmonary hypertension of the newborn (PPHN). We aimed to compare oral sildenafil and bosentan as monotherapy in the treatment of neonates with PPHN. Study design In this single-centre open-label randomized controlled trial (RCT), term and late preterm neonates with PPHN, defined as pulmonary arterial systolic pressure (PASP) > 35 mmHg and requiring fraction of inspired oxygen (FiO2) > 0.21, were randomized to receive oral sildenafil and bosentan. The primary outcome was reduction of PASP by 25% within 48 h after start of drug. Results Thirty-six neonates were analyzed (18 in each group). Initial PASPs were similar in both groups. The median (IQR) time for the primary outcome (PASP to reduce by 25% within 48 h) was 36 (24–48) h and 96 (48–120) h in sildenafil and bosentan groups respectively (p = 0.008). There was also a higher need to add other pulmonary vasodilators in bosentan group as compared to sildenafil group (p = 0.006). Conclusion Sildenafil was associated with quicker reduction of PASP and FiO2 in neonates with PPHN, as compared to bosentan. Large multicentre blinded trials to assess efficacy and safety of bosentan in comparison with other pulmonary vasodilators would help to get a clearer understanding of its role in the management of PPHN, particularly for use in resource-limited settings that lack iNO. Clinical trial registration: https://ctri.nic.in/Clinicaltrials/rmaindet.php? trialid=63997&EncHid=39716.16132&modid=1&compid=19[CTRI/2022/06/043328].

Background and Objective: Off‐label pulmonary arterial hypertension (PAH)‐targeted drugs are commonly prescribed for non‐operated chronic thromboembolic pulmonary hypertension (CTEPH), but their effect on the long‐term prognosis of CTEPH remains unknown. This study investigated the effect of off‐label PAH‐targeted drugs on the long‐term survival of CTEPH patients. Methods: CTEPH patients were enrolled from a prospective multicentre national registry. Except for licensed riociguat and treprostinil, other PAH‐targeted drugs were off‐label. In the original and propensity score–matched (PSM) samples, five‐year survival was compared in two groups: (a) patients not receiving off‐label PAH‐targeted drugs (control) versus (b) patients receiving off‐label PAH‐targeted drugs (treatment). The latter group was investigated for the effect of started off‐label PAH‐targeted drugs at baselines (initial) or during follow‐up (subsequent). Results: Of 347 enrolled patients, 212 were treated with off‐label PAH‐targeted drugs initially (n = 173) or subsequently (n = 39), and 135 were untreated. The 1‐, 2‐, 3‐ and 5‐year survival of the treatment group was significantly higher than that of the control group (97.1% vs. 89.4%, 92.3% vs. 82.1%, 83.2% vs. 75.1% and 71.1% vs. 55.3%, respectively, log‐rank test, p = 0.005). Initial treatment was correlated with better 5‐year survival after excluding patients with subsequent treatment to reduce the immortal‐time bias (hazard ratio: 0.611; 95% CI: 0.397–0.940; p = 0.025). In PSM samples, patients given initial treatment showed significantly better 5‐year survival than untreated patients (68.9% vs. 49.3%, log‐rank test, p = 0.008). Conclusion: Off‐label targeted drugs contributed to improved long‐term survival in CTEPH patients receiving pharmacotherapies. [ABSTRACT FROM AUTHOR]

Bosentan, an endothelin receptor antagonist (ERA), has potential anti-atherosclerotic properties. We investigated the complementary effects of bosentan and atorvastatin on the progression and composition of the atherosclerotic lesions in diabetic mice. Forty-eight male ApoE−/− mice were fed high-fat diet (HFD) for 14 weeks. At week 8, diabetes was induced with streptozotocin, and mice were randomized into four groups: (1) control/COG: no intervention; (2) ΒOG: bosentan 100 mg/kg/day per os; (3) ATG: atorvastatin 20 mg/kg/day per os; and (4) BO + ATG: combined administration of bosentan and atorvastatin. The intra-plaque contents of collagen, elastin, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-a (TNF-a), matrix metalloproteinases (MMP-2, -3, -9), and TIMP-1 were determined. The percentage of lumen stenosis was significantly lower across all treated groups: BOG: 19.5 ± 2.2%, ATG: 12.8 ± 4.8%, and BO + ATG: 9.1 ± 2.7% compared to controls (24.6 ± 4.8%, p < 0.001). The administration of both atorvastatin and bosentan resulted in significantly higher collagen content and thicker fibrous cap versus COG (p < 0.01). All intervention groups showed lower relative intra-plaque concentrations of MCP-1, MMP-3, and MMP-9 and a higher TIMP-1concentration compared to COG (p < 0.001). Importantly, latter parameters presented lower levels when bosentan was combined with atorvastatin compared to COG (p < 0.05). Bosentan treatment in diabetic, atherosclerotic ApoE−/− mice delayed the atherosclerosis progression and enhanced plaques' stability, showing modest but additive effects with atorvastatin, which are promising in atherosclerotic cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Background: In order to measure the plasma levels of Losartan and Bosentan, a sensitive Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) technique was developed. Methods: To compare bioavailability, the Area Under the Curve (AUC), peak plasma concentration (Cmax), and time to Cmax (Tmax) were employed. The standard curve (150-2400 ng/ml) was linear (R²=0.999), relative errors were between 2.4 to 10.05% and the coefficient of variation (CV%) ranged from 1.52 to 10.88. A single dosage (test and reference) was used for the in vivo investigation, which involved 16 healthy individuals. Results: The AUC0-48, AUC0-, Cmax, and Tmax of the test and reference had no statistically significant differences. The Cmax and 95% confidence intervals of the ratio of Cmax of the two formulations were 0.93-0.96 and 97.6-135%, respectively. Conclusion: Therefore, it was established that generic Bosentan was equivalent to Bosentan from Actelion and that both medications could be regarded as equally effective in clinical settings. The blood level of Bosentan could be measured using this straightforward procedure in all hospital laboratories. [ABSTRACT FROM AUTHOR]

The purpose of this study was to prepare and evaluate multiple unit mini tablets (MTs) of prolonged released (PR) bosentan (BSN) and fast release (FR) sildenafil citrate (SDC) on the basis of encapsulation method for the effective management of pulmonary artery hypertension. The system consists of MTs are in the form of uncoated tablets containing the superdisintegrating agents where as the PRMTs contains the polymer with film coating. All the units are prepared by direct compression method and encapsulated using size 1 hard gelatin capsule shells. The formulations were evaluated for differential scanning calorimetry, dissolution test and post compression studies for their quality attributes and it was found that all the parameters were in the acceptable limits. The optimized formulation for BSN PRMTs i.e BS3 which contains 5 % HPMC K15M shows a promising sustained release profile of 82.31 % in 24 h similarly FRMTs of SDC of formulation SD6 that having 3 % of magnesium aluminium silicate shows about 90 % of drug release within 15 min. The in-vivo pharmacokinetic characterization of the system was carried out using wister rats where the AUC value for SDC FRMTs and BSN PRMTs was found to be 94256.88625 ± 123.65 ng h/mL and 142438.084 ± 324.11 ng h/mL respectively. The other pharmacokinetics are also determined and found to be satisfactory. The six months stability samples showed no significant change in the drug content, hardness and uniformity of the content of the optimized formulations.

In this work, a solid-state electrochemical sensor relying on potentiometric transduction was constructed and optimized to detect Bosentan (BOS) in its pharmaceutical dosage form and human plasma. BOS is useful in pulmonary hypertension management as a nonselective endothelin receptor antagonist. A printed circuit board has been constructed and used as a substrate for microfabricated Cu electrodes. In comparison to a microfabricated control (Cu/ISM) electrode, the sensor potential signal drift was enhanced, and the response time was reduced by using multi-walled carbon nanotubes (MWCNTs) as an ion-to-electron transducer layer. According to IUPAC requirements, the suggested BOS sensors have been electrochemically characterized, and the linear dynamic range is (1.0 × 10−8 to 1.0 × 10−5) M with a limit of detection of 6.28 × 10−9 M and 6.12 × 10−9 M for MWCNT-based sensor (Cu/CNT-NC/ISM) and control sensor (Cu/ISM), respectively. The described sensors have been used successfully to selectively determine BOS in dosage form and human plasma without any pre-treatment steps.

This open-label, two-way, crossover, phase Ib drug–drug interaction study investigated whether the pharmacokinetics (PKs) and safety profile of lurbinectedin (LRB) are affected by co-administration of a moderate CYP3A4 inducer (bosentan, BOS) in adult patients with advanced solid tumors. Eleven patients were randomly assigned to Sequence 1 (LRB + BOS in Cycle 1 [C1] and LRB alone in Cycle 2 [C2]) or Sequence 2 (LRB alone in C1 and LRB + BOS in C2), and finally, eight patients (four per sequence) were considered evaluable for PK assessment. LRB (3.2 mg/m2, 1 h [h], intravenous) was administered alone or combined with multiple BOS administration (125 mg/12 h oral; 5.5 days). Co-administration with BOS decreased the systemic total exposure (area under the curve, AUC) of LRB by 21% for AUC0–t and 20% for AUC0–∞ and increased clearance by 25%. Co-administration with BOS did not significantly modify the unbound plasma LRB PK parameters. BOS increased the conversion of LRB to its metabolite M1, with no changes on its metabolite M4. The LRB safety profile was consistent with the toxicities previously described for this drug. No differences in terms of toxicity were found between LRB with and without BOS. In summary, the magnitude of the observed changes precludes a clinically relevant effect of BOS co-administration on LRB exposure and its safety profile. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim is to showcase the effectiveness and safety of bosentan or ambrisentan in individuals diagnosed with idiopathic pulmonary fibrosis (IPF) and offer fresh evidence for the management of this condition. MATERIALS AND METHODS: For this research, we conducted a meta-analysis of randomized controlled trials by searching various databases, including the Cochrane Library, Excerpta Medica Database, PubMed, and Web of Science. The retrieval was conducted until November 2021. We analyzed the variances in 6-minute walk distance (6MWD), death, diffusion capacity for carbon monoxide (DLCO), forced vital capacity (FVC), hospitalization, IPF worsening, mean pulmonary arterial pressure, serious adverse events (SAEs), Short Form-36 improved, and St. George's Respiratory Questionnaire between the treatment and control groups. RESULTS: A sum of six studies involving 1928 participants were found to meet the inclusion criteria. The quality of evidence was high. The control group had significantly higher values for 6MWD, DLCO, and FVC compared to the ambrisentan treatment group. The rates of hospitalization and IPF worsening were considerably greater in comparison with the control group. The bosentan group exhibited significantly reduced rates of hospitalization and IPF worsening in comparison with the control group. Both drugs did not cause any raising in death or SAEs when in comparison with the control group. CONCLUSIONS: The findings of this research validate the effectiveness and safety of bosentan for treating IPF patients. This medication can enhance the quality of life for individuals with IPF without causing any significant increase in SAEs. However, it does not have a notable influence on the long-term prognosis. The findings of this research do not endorse the utilization of ambrisentan in individuals diagnosed with IPF. [ABSTRACT FROM AUTHOR]

Current management of patients with congenital heart disease has increased their survival into adulthood. This is accompanied by potential cardiac complications, including pulmonary hypertension associated with congenital heart disease (PAH-CHD). PAH-CHD constitutes a challenging subgroup of pulmonary hypertension and requires expert management to improve quality of life and prognosis. Novel agents have shown a significant improvement in morbidity and mortality in patients with pulmonary arterial hypertension. However, the long-term effects of these medications on PAH-CHD patients remain somewhat uncertain, necessitating treatment plans largely founded on the clinical experience of the healthcare providers. The aim of this review is to summarize the current evidence and future perspectives regarding treatment strategies for PAH-CHD to help better guide management of this complex disease. [ABSTRACT FROM AUTHOR]

The effects of endothelin-1 (ET-1) on erythrocytes from sickle cell disease (SCD) patients have been described, but mechanisms of ET-1 regarding primary erythrocyte functions remain unknown. ET-1 is a vasoconstrictor peptide produced by endothelial cells, and the expression of ET-1 is increased in SCD. The present study used ex vivo experiments with sickle cell erythrocytes, ET-1, and bosentan, a dual antagonist of ETA and ETB receptors. We performed a hemoglobin S (HbS) polymerization assay with three concentrations of ET-1 (1, 20, and 50 pg/mL) and bosentan (100 nmol/L). ET-1 increased HbS polymerization at all concentrations, and this effect was suppressed by bosentan. For the deformability assay, red blood cells (RBCs) were incubated on a Sephacryl column with the same concentrations of ET-1 and bosentan. ET-1 decreased deformability, and this effect was reversed by bosentan. To observe erythrocyte adhesion, ET-1 and bosentan were incubated with RBCs in thrombospondin-coated 96-well plate, which demonstrated that ET-1 decreased adhesion but that bosentan enhanced adhesion. We also assessed erythrocyte apoptosis and observed decreased eryptosis induced by ET-1, and these effects were inhibited bosentan. Thus, these findings demonstrated that ET-1 modulates HbS polymerization, erythrocyte deformability, adhesion to thrombospondin, and eryptosis, and these effects were suppressed or enhanced by bosentan. [ABSTRACT FROM AUTHOR]

Bosentan, an endothelin receptor antagonist (ERA), has potential anti-atherosclerotic properties. We investigated the complementary effects of bosentan and atorvastatin on the progression and composition of the atherosclerotic lesions in diabetic mice. Forty-eight male ApoE−/− mice were fed high-fat diet (HFD) for 14 weeks. At week 8, diabetes was induced with streptozotocin, and mice were randomized into four groups: (1) control/COG: no intervention; (2) ΒOG: bosentan 100 mg/kg/day per os; (3) ATG: atorvastatin 20 mg/kg/day per os; and (4) BO + ATG: combined administration of bosentan and atorvastatin. The intra-plaque contents of collagen, elastin, monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-a (TNF-a), matrix metalloproteinases (MMP-2, -3, -9), and TIMP-1 were determined. The percentage of lumen stenosis was significantly lower across all treated groups: BOG: 19.5 ± 2.2%, ATG: 12.8 ± 4.8%, and BO + ATG: 9.1 ± 2.7% compared to controls (24.6 ± 4.8%, p < 0.001). The administration of both atorvastatin and bosentan resulted in significantly higher collagen content and thicker fibrous cap versus COG (p < 0.01). All intervention groups showed lower relative intra-plaque concentrations of MCP-1, MMP-3, and MMP-9 and a higher TIMP-1concentration compared to COG (p < 0.001). Importantly, latter parameters presented lower levels when bosentan was combined with atorvastatin compared to COG (p < 0.05). Bosentan treatment in diabetic, atherosclerotic ApoE−/− mice delayed the atherosclerosis progression and enhanced plaques’ stability, showing modest but additive effects with atorvastatin, which are promising in atherosclerotic cardiovascular diseases.

This study aimed to evaluate the effectiveness of bosentan as a protective agent on the rats cheek mucosa for Methotrexate-induced oral mucositis. Twenty-four Wister-albino rats, about 12-16 weeks and weighing 300-400 g, were used. The animals were divided into three groups. In the first control group, the second group was treated with methotrexate (80 mg/kg), and the third group was treated with methotrexate and bosentan 60 mg/kg. The microscopical parameters were estimated, the pro-inflammatory marker (TNF-α) and intercellular adhesive molecule-1(ICAM-1) measurement in the buccal mucosa. The animals were sacrificed on day 15, and the buccal mucosa was dissected for histological and immunohistochemical analysis. Bosentan decreased the severity of the Methotrexate-induced oral mucositis by a significant decrease in the histological score and a significant decrease in TNF-α and ICAM-1 immune histochemical expression at day fifteen. Bosentan at a concentration of 60 mg/kg/day produced protection against Methotrexate-induced oral mucositis by its anti-inflammatory action and reduction in the histological score and, therefore, can be used as a protective agent against Methotrexate-induced oral mucositis.

Pulmonary hypertension (PH) is a significant health problem that contributes to high morbidity and mortality in diverse cardiac, pulmonary, and systemic diseases in children. Evidence-based advances in PH care have been challenged by a paucity of quality endpoints for assessing clinical course and the lack of robust clinical trial data to guide pharmacologic therapies in children. While the landmark adult AMBITION trial demonstrated the benefit of up-front combination PH therapy with ambrisentan and tadalafil, it remains unknown whether upfront combination therapy leads to more rapid and sustained clinical benefits in children with various categories of PH. In this article, we describe the inception of the Kids Mod PAH Trial, a multicenter Phase III trial, to address whether upfront combination therapy (sildenafil and bosentan vs. sildenafil alone) improves PH outcomes in children, recognizing that marked differences between the etiology and therapeutic response between adults and children exist. The primary endpoint of this study is WHO functional class (FC) 12 months after initiation of study drug therapy. In addition to the primary outcome, secondary endpoints are being assessed, including a composite measure of time to clinical worsening, WHO FC at 24 months, echocardiographic assessment of PH and quantitative assessment of right ventricular function, 6-min walk distance, and NT-proBNP levels. Exploratory endpoints include selected biomarkers, actigraphy, and assessments of quality of life. This study is designed to pave the way for additional clinical trials by establishing a robust infrastructure through the development of a PPHNet Clinical Trials Network. [ABSTRACT FROM AUTHOR]

Despite the increasing evidence supporting the efficacy of ambrisentan and bosentan in improving functional classes among pediatric patients with pulmonary arterial hypertension (PAH), there is a lack of information regarding their cost implications. Therefore, the objective of this study is to assess the cost-utility of bosentan compared to ambrisentan for the treatment of pediatric patients with PAH in Colombia. We employed a Markov model to estimate the costs and quality-adjusted life-years (QALYs) associated with the use of ambrisentan or bosentan in pediatric patients diagnosed with pulmonary arterial hypertension (PAH). To ensure the reliability of our findings, we conducted sensitivity analyses to assess the robustness of the model. In our cost-effectiveness analysis, we evaluated the outcomes at a willingness-to-pay (WTP) threshold of US$5,180. The expected annual cost per patient receiving ambrisentan was estimated to be $16,055 (95% CI 15,937 –16,172), while for bosentan it was $14,503 (95% CI 14,489 –14,615). The QALYs per person estimated for ambrisentan were 0.39 (95% CI 0.381–0.382), whereas for bosentan it was 0.40 (95% CI 0.401–0.403). Our economic evaluation shows that ambrisentan is not cost-effective regarding bosentan to in treating pulmonary arterial hypertension in C. [ABSTRACT FROM AUTHOR]

Background: To discover the optimal solvent amounts for using in a particular application, it is vital to achieve some useful information in regard with suitable neat or mixed solvent and drugs equilibrium solubility in them. It is known that the low solubility of drugs such as bosentan (BST) in water negatively effects in vitro and in vivo kinetics of dissolution, affecting in turn its bioavailability along with making several difficulties around designing its liquid formulations. Methods: Solubility of BST in some mixtures of polyethylene glycol 400 (PEG 400) and water was experimentally determined at T = (293.15 to 313.15) K by using a common shake-flask technique followed by UV-visible spectroscopic method. The experimental solubility data in PEG 400 mass fraction (w1) of 0.0 to 1.0 at 298.15 K and in w1=0.0, 0.5 and 1.0 at other temperatures were then correlated by cosolvency models including the Jouyban-Acree, the Jouyban-Acree-van’t Hoff, and the double log-log models and some un-measured solubility data were predicted based on the obtained trained models. Results: The results presented that the aqueous solubility of BST is increased by increasing mass fraction of PEG 400 as well as increasing temperature and reached the maximum value in neat PEG 400 at 313.15 K. Conclusion: The BST solubility in water improved by addition of PEG 400 into it. According to the average relative deviations obtained from the back-computed data with trained models which were < 8.0%, it concluded that the selected models were able to predict the un-measured data with high reliability.

Abstract Pulmonary hypertension (PH) is a significant health problem that contributes to high morbidity and mortality in diverse cardiac, pulmonary, and systemic diseases in children. Evidence‐based advances in PH care have been challenged by a paucity of quality endpoints for assessing clinical course and the lack of robust clinical trial data to guide pharmacologic therapies in children. While the landmark adult AMBITION trial demonstrated the benefit of up‐front combination PH therapy with ambrisentan and tadalafil, it remains unknown whether upfront combination therapy leads to more rapid and sustained clinical benefits in children with various categories of PH. In this article, we describe the inception of the Kids Mod PAH Trial, a multicenter Phase III trial, to address whether upfront combination therapy (sildenafil and bosentan vs. sildenafil alone) improves PH outcomes in children, recognizing that marked differences between the etiology and therapeutic response between adults and children exist. The primary endpoint of this study is WHO functional class (FC) 12 months after initiation of study drug therapy. In addition to the primary outcome, secondary endpoints are being assessed, including a composite measure of time to clinical worsening, WHO FC at 24 months, echocardiographic assessment of PH and quantitative assessment of right ventricular function, 6‐min walk distance, and NT‐proBNP levels. Exploratory endpoints include selected biomarkers, actigraphy, and assessments of quality of life. This study is designed to pave the way for additional clinical trials by establishing a robust infrastructure through the development of a PPHNet Clinical Trials Network.

[Display omitted] In this study, high energy ball milling and nano spray drying were used to prepare amorphous solid dispersions of bosentan in copovidone for the first time. In particular, the impact of this polymer on the bosentan amorphization kinetics was investigated. Copovidone was shown to facilitate the amorphization of bosentan upon ball milling. As a result, bosentan was dispersed in copovidone at the molecular level, forming amorphous solid dispersions, regardless of the ratio of the compounds. The similarity between the values of the adjustment parameter that describes the goodness of fit of the Gordon-Taylor equation to the experimental data (K = 1.16) and that theoretically calculated for an ideal mixture (K = 1.13) supported these findings. The kind of coprocessing method determined the powder microstructure and the release rate. The opportunity to prepare submicrometer-sized spherical particles using nano spray drying was an important advantage of this technology. Both coprocessing methods allowed the formation of long-lasting supersaturated bosentan solutions in the gastric environment with maximum concentrations reached ranging from four (11.20 μg/mL) to more than ten times higher (31.17 μg/mL) than those recorded when the drug was vitrified alone (2.76 μg/mL). Moreover, this supersaturation lasted for a period of time at least twice as long as that of the amorphous bosentan processed without copovidone (15 min vs. 30–60 min). Finally, these binary amorphous solid dispersions were XRD-amorphous for a year of storage under ambient conditions. [ABSTRACT FROM AUTHOR]

Patients with systemic sclerosis (SSc) develop various vascular disorders, including digital ulcers (DUs), which are sometimes intractable. Bosentan is a dual endothelin receptor antagonist expected to suppress the development of new DUs. The objective of this study was to analyze retrospectively Japanese SSc patients treated with bosentan and investigate its efficacy and safety. We analyzed 40 patients who visited our department from 2009 to 2022 and were treated with bosentan. Of the 25 patients who were able to continue bosentan, 64% (16 patients) were cured by 16 weeks. New DUs occurred in 5.9% (2/34) of patients and the number of new DUs per person was 0.1. Adverse events occurred in 45% (18/40), and hepatic dysfunction was occurred most frequently at 32.5% (13/40). In univariate analysis, hepatic dysfunction was significantly high in patients with low modified Rodnan total skin thickness score. Antimitochondria‐antibody‐positive patients were more likely to develop liver dysfunction. Hepatic dysfunction was improved without the reduction or discontinuation, dose reduction, discontinuation, or concomitant use of ursodeoxycholic acid. These results suggest that bosentan can be selected as an additional treatment for DU, which is difficult to treat with existing therapies, while carefully monitoring hepatic function. [ABSTRACT FROM AUTHOR]

Abstract Background Nonarteritic anterior ischemic optic neuropathy (NAAION) is a major cause of blindness in individuals over 50 years of age, with no available effective treatment. The oral dual endothelin receptor antagonist, bosentan, increases retinal optic nerve head blood flow in healthy humans and glaucoma patients. The objective of this trial is to assess the efficacy of bosentan administered at the acute stage in improving outcomes in NAAION patients. Methods ENDOTHELION (ENDOTHELin antagonist receptor in Ischemic Optic Neuropathy) is a phase III, interventional, prospective, multicentre, placebo-controlled randomised double-blind clinical trial. The primary outcome is change in the visual field mean deviation (MD) at 3 months (Humphrey 30-2 SITA standard programme). Secondary outcomes include MD and visual acuity changes up to 24 months, changes in peripapillary retinal nerve fibre and macular ganglion cell layer thickness in the affected eye, as measured by optical coherence tomography, rate of NAAION bilateralisation at 2 years, and quality-of-life. Patients over 50 years of age presenting with typical NAAION of recent onset (less than 21 days) are randomly assigned to either 125 mg oral bosentan or placebo, twice a day, during 8 weeks. Besides visits during the treatment phase, patients attend follow-up visits at 2, 3, 6, 12 and 24 months. The inclusion of patients began in August 2015 at five French University hospital ophthalmology departments and two specialised ophthalmology centres. It is planned to include 86 patients in this trial. To date we have included 72 patients and 49 have completed the full follow-up process. Discussion An endothelin receptor antagonist is a potential approach to improving the anatomical and functional prognosis of patients with NAAION. This multicentre double-blind randomised controlled trial is an opportunity to assess (1) the effect of bosentan on the structure and function of the optic nerve in NAAION, at 3 months, (2) the effect of bosentan on the bilateralisation rate at 24 months and (3) the tolerance profile of bosentan in this population. Trial registration ClinicalTrials.gov NCT02377271 . Registered on March 3, 2015.

Endothelin-1 (ET-1) has been implicated in the pathogenesis of cardiac fibrosis. Stimulation of endothelin receptors (ETR) with ET-1 leads to fibroblast activation and myofibroblast differentiation, which is mainly characterized by an overexpression of α-smooth muscle actin (α-SMA) and collagens. Although ET-1 is a potent profibrotic mediator, the signal transductions and subtype specificity of ETR contributing to cell proliferation, as well as α-SMA and collagen I synthesis in human cardiac fibroblasts are not well clarified. This study aimed to evaluate the subtype specificity and signal transduction of ETR on fibroblast activation and myofibroblast differentiation. Treatment with ET-1 induced fibroblast proliferation, and synthesis of myofibroblast markers, α-SMA, and collagen I through the ETAR subtype. Inhibition of Gαq protein, not Gαi or Gβγ, inhibited these effects of ET-1, indicating the essential role of Gαq protein-mediated ETAR signaling. In addition, ERK1/2 was required for ETAR/Gαq axis-induced proliferative capacity and overexpression of these myofibroblast markers. Antagonism of ETR with ETR antagonists (ERAs), ambrisentan and bosentan, inhibited ET-1-induced cell proliferation and synthesis of α-SMA and collagen I. Furthermore, ambrisentan and bosentan promoted the reversal of myofibroblasts after day 3 of treatment, with loss of proliferative ability and a reduction in α-SMA synthesis, confirming the restorative effects of ERAs. This novel work reports on the ETAR/Gαq/ERK signaling pathway for ET-1 actions and blockade of ETR signaling with ERAs, representing a promising therapeutic strategy for prevention and restoration of ET-1-induced cardiac fibrosis. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) is a chronic and progressive disease that, if left untreated, shortens the life expectancy of patients. Endothelin receptor antagonists, such as macitentan and bosentan, play an essential role in improving the patient's symptoms, quality of life, and life expectancy. This study aimed to evaluate the cost-utility of macitentan compared with bosentan in treating PAH from the health system perspective in Iran. For evaluating the cost-effectiveness of macitentan, a Markov model consisting of 5 states, functional class (FC) I, FC II, FC III, FC IV, and death, was designed using the TreeAge software. The lifetime time horizon and a 3-month cycle length were set. Patients entered the model from FC II or FC III states based on the initial probabilities. Costs were measured in US dollars (USD), and outcomes were measured in terms of quality quality-adjusted life-years (QALYs). Consequently, the incremental cost-effectiveness ratio (ICER) was calculated. In addition, sensitivity analysis was performed to determine the robustness of the model by examining the possible effects of uncertainties on the final result. The costs of treatment with macitentan and bosentan in PAH in Iran were calculated at 19 429 and 17 246 USD, and the outcomes were 4.02 and 3.04 QALYs, respectively. Therefore, ICER was calculated at 2233.46 USD/QALY. One-way sensitivity analysis demonstrates that the model is robust; nevertheless, it is most sensitive to the price of macitentan and bosentan. Treatment with macitentan was associated with both higher costs and QALYs than bosentan. Nevertheless, it is considered the cost-effective treatment strategy in Iran given that the calculated ICER falls below the willingness to pay threshold. [ABSTRACT FROM AUTHOR]

This open-label, two-way, crossover, phase Ib drug–drug interaction study investigated whether the pharmacokinetics (PKs) and safety profile of lurbinectedin (LRB) are affected by co-administration of a moderate CYP3A4 inducer (bosentan, BOS) in adult patients with advanced solid tumors. Eleven patients were randomly assigned to Sequence 1 (LRB + BOS in Cycle 1 [C1] and LRB alone in Cycle 2 [C2]) or Sequence 2 (LRB alone in C1 and LRB + BOS in C2), and finally, eight patients (four per sequence) were considered evaluable for PK assessment. LRB (3.2 mg/m2, 1 h [h], intravenous) was administered alone or combined with multiple BOS administration (125 mg/12 h oral; 5.5 days). Co-administration with BOS decreased the systemic total exposure (area under the curve, AUC) of LRB by 21% for AUC0–t and 20% for AUC0–∞ and increased clearance by 25%. Co-administration with BOS did not significantly modify the unbound plasma LRB PK parameters. BOS increased the conversion of LRB to its metabolite M1, with no changes on its metabolite M4. The LRB safety profile was consistent with the toxicities previously described for this drug. No differences in terms of toxicity were found between LRB with and without BOS. In summary, the magnitude of the observed changes precludes a clinically relevant effect of BOS co-administration on LRB exposure and its safety profile.

The molar solubility of bosentan (BST) in mixtures of ethylene glycol (EG) + water at different temperatures from 293.15 to 313.15 K was measured by using the shake flask technique. Experimental solubility increased with increasing temperature and mass fraction of cosolvent; so that, the largest solubility was found in neat cosolvent at 313.15 K. The cosolvency models of Jouyban–Acree and its combined version with van't Hoff equation (Jouyban–Acree–van't Hoff model) were used for correlation of BST solubility data with the low values of mean relative deviations (MRD% ≤ 8.1). Furthermore, some untested data were predicted based on the achieved trained models at 298.15 K. X-ray powder diffraction was also served to analyze the equilibrium solid phase crystal of BST and the results turns out that no polymorphic transformation, solvate formation or crystal transition during the whole solvent crystallization process. [ABSTRACT FROM AUTHOR]

Introduction The prevalence of persistent pulmonary hypertension of newborn (PPHN) has been estimated 1.9/1000 live births. Although the efficacy of inhaled nitric oxide and extracorporeal membrane oxygenation in PPHN is well established but it is difficult to administer and monitor in resource limited countries. Owing to this, other treatment options need to be evaluated. Method This is a prospective observational study conducted in the Pediatric Cardiology Department, NICVD, Karachi, from February 2020 to October 2020 after the approval from the Institutional Ethical Review Committee. All the neonates referred to our Unit were screened by echocardiography (echo) and those who fulfilled the inclusion criteria were included. Echo were done before starting sildenafil and after 72 h to assess the pressure gradient across tricuspid valve and right to left or bidirectional shunt across patent ductus arteriosus, patent foramen ovale, or both. Sildenafil was started with a dose of 1 mg/kg/dose thrice a day and increased to 2 mg/kg/dose after 48 h if partial pressure of oxygen (PO1] did not increase. In neonates who did not respond to increased dose of Sildenafil were added on oral Bosentan 1 mg/kg/dose twice a day. Results Total 82 newborns were enrolled. Fifty-two patients improved after 48 h so were continued on same treatment. Sildenafil dose was increased in 30 (37.9%) patients whose PO2 did not increase to at least 10% from baseline after 48 h of starting treatment. Three patients expired within 48–72 h. Out of 27 remaining patients, only four responded whereas 23 patients did not show any improvement. In these patients, Bosentan was supplemented along with sildenafil. Conclusion The results of our study show effectiveness of oral Sildenafil in treating PPHN. The overall improvement observed in the patients was overwhelming. Combination of Sildenafil with Bosentan is beneficial in patients who did not respond on Sildenafil alone. [ABSTRACT FROM AUTHOR]

BackgroundThere is little evidence of the effectiveness of switching from the endothelin receptor antagonists (ERAs) bosentan and ambrisentan to a novel ERA, macitentan, in patients with pulmonary arterial hypertension (PAH). Therefore, a systematic review and meta-analysis was performed to evaluate the efficacy and safety of patients with PAH switching from other ERAs to macitentan.MethodsWe retrieved the relevant literature published before January 2022 for the meta-analysis from the PubMed, EMBASE, and Cochrane Library databases. Efficacy included changes in the 6-min walk distance (6MWD), World Health Organization functional class (WHO-FC), N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, hemodynamics, echocardiography and survival.ResultsNine studies, consisting of 408 PAH patients, that met the inclusion criteria were included. The switch from bosentan or ambrisentan to macitentan effectively increased the 6MWD by 20.71 m (95% CI: 10.35-31.07, P < 0.00001, I2 = 0%). Six months after conversion, the tricuspid annular plane systolic excursion was found to improve from 19.0 ± 4.0 to 21.0 ± 5.0 mm in adults and from 16.00 ± 5.0 to 18.25 ± 4.8 mm in children. Ordinal logistic regression showed that the WHO-FC significantly improved by 0.412 (95% CI: 0.187-0.908, P = 0.028). The switch did not show significant improvement in NT-proBNP levels. In addition, the switch was well tolerated.ConclusionThe switch from bosentan or ambrisentan to macitentan significantly increased the 6MWD in PAH patients, improved the WHO-FC, and exerted safety benefits. The effects of the switch on NT-proBNP levels, hemodynamics, and echocardiography still need to be further confirmed.Systematic review registration[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021292554].

Bosentan is choice of drug for pulmonary arterial hypertension. It belongs to BCS class-II category. Due to poor solubility in aqueous media, treatment leads to frequent dosing & increasing cost of therapy subsequently. One cannot unseen the shortcomings of commonly existing solubility enhancement techniques such as physical and chemical modifications of the drug, salt formation, solid dispersion, complexation because of the need for sophisticated equipment, decreased yield, incomplete removal of organic solvents, etc. The novel hybridization technique is a fusion of complexation and liquisolid technique. In this research work, Bosentan was complexed with captisol in the first step. In the second step, the complex was dispersed in non-volatile solvent & mixed with the carrier using mortar-pestle followed by the addition of coating material to form a free-flowing powder. It was then compressed into tablets by mixing with other excipients. The formulation was characterized by phase solubility study, DSC, FTIR, and XRD to confirm drug-excipients compatibility, crystallinity etc. The phase solubility study showed ∼28.85 fold increase in solubility. From screening, Avicel PH101 & Parteck SLC 500 as carrier and coating material respectively & PEG-600 as non-volatile solvent were selected. Explotab as super-disintegrant and Pearlitol 100SD as direct compressible excipient were used. Optimization by 32 factorial design gave Bosentan tablet with disintegrate in time of 7–8 min and showed 87.264±0.823% drug release in 30 min higher than marketed tablet i.e. 61.750±1.226%. From the stability study, the Novel hybridization technique was proved as a choice for solubility enhancement.

Background: Nonarteritic anterior ischemic optic neuropathy (NAAION) is a major cause of blindness in individuals over 50 years of age, with no available effective treatment. The oral dual endothelin receptor antagonist, bosentan, increases retinal optic nerve head blood flow in healthy humans and glaucoma patients. The objective of this trial is to assess the efficacy of bosentan administered at the acute stage in improving outcomes in NAAION patients.Methods: ENDOTHELION (ENDOTHELin antagonist receptor in Ischemic Optic Neuropathy) is a phase III, interventional, prospective, multicentre, placebo-controlled randomised double-blind clinical trial. The primary outcome is change in the visual field mean deviation (MD) at 3 months (Humphrey 30-2 SITA standard programme). Secondary outcomes include MD and visual acuity changes up to 24 months, changes in peripapillary retinal nerve fibre and macular ganglion cell layer thickness in the affected eye, as measured by optical coherence tomography, rate of NAAION bilateralisation at 2 years, and quality-of-life. Patients over 50 years of age presenting with typical NAAION of recent onset (less than 21 days) are randomly assigned to either 125 mg oral bosentan or placebo, twice a day, during 8 weeks. Besides visits during the treatment phase, patients attend follow-up visits at 2, 3, 6, 12 and 24 months. The inclusion of patients began in August 2015 at five French University hospital ophthalmology departments and two specialised ophthalmology centres. It is planned to include 86 patients in this trial. To date we have included 72 patients and 49 have completed the full follow-up process.Discussion: An endothelin receptor antagonist is a potential approach to improving the anatomical and functional prognosis of patients with NAAION. This multicentre double-blind randomised controlled trial is an opportunity to assess (1) the effect of bosentan on the structure and function of the optic nerve in NAAION, at 3 months, (2) the effect of bosentan on the bilateralisation rate at 24 months and (3) the tolerance profile of bosentan in this population.Trial Registration: ClinicalTrials.gov NCT02377271 . Registered on March 3, 2015. [ABSTRACT FROM AUTHOR]

The objective of our study was to contribute to the characterization of monocrotaline-induced pulmonary arterial hypertension (PAH) in a rat model, with emphasis on the renin–angiotensin–aldosterone system, parameters of oxidative stress, the activity of matrix metalloproteinases, and erythrocyte parameters. Moreover, we aimed to analyze the effects of bosentan. Experiments were performed on 12-week-old male Wistar rats randomly assigned to 3 groups: control, monocrotaline-treated (60 mg/kg), and monocrotaline combined with bosentan (300 mg/kg/day). Our study confirmed the well-known effects of monocrotaline administration on lungs and the right ventricle, as well as pulmonary arterial pressure. In addition, we observed activation of the alternative pathway of the renin–angiotensin system, namely an increase in angiotensin (Ang) 1–7 and Ang 1-5 together with an increase in Ang I, but without any change in Ang II level, and downregulation of aldosterone 4 weeks after monocrotaline administration. For the first time, modifications of erythrocyte Na,K-ATPase enzyme kinetics were demonstrated as well. Our observations do not support data obtained in PAH patients showing an increase in Ang II levels, increase in oxidative stress, and deterioration in RBC deformability. Although bosentan primarily targets the vascular smooth muscle, our study confirmed its antioxidant effect. The obtained data suggest that besides the known action of bosentan, it decreases heart rate and increases erythrocyte deformability, and hence could have a beneficial hemodynamic effect in the PAH condition. [ABSTRACT FROM AUTHOR]

We examined the effect of intermittent hypoxia (IH, a hallmark feature of sleep apnea) on adipose tissue lipolysis and the role of endothelin-1 (ET-1) in this response. We hypothesized that IH can increase ET-1 secretion and plasma free fatty acid (FFA) concentrations. We further hypothesized that inhibition of ET-1 receptor activation with bosentan could prevent any IH-mediated increase in FFA. To test this hypothesis, 16 healthy male participants (32 ± 5 yr, 26 ± 2 kg/m²) were exposed to 30 min of IH in the absence (control) and presence of bosentan (62.5 mg oral twice daily for 3 days prior). Arterial blood samples for ET-1, epinephrine, and FFA concentrations, as well as abdominal subcutaneous adipose tissue biopsies (to assess transcription of cellular receptors/proteins involved in lipolysis), were collected. Additional proof-of-concept studies were conducted in vitro using primary differentiated human white preadipocytes (HWPs). We show that IH increased circulating ET-1, epinephrine, and FFA (P < 0.05). Bosentan treatment reduced plasma epinephrine concentrations and blunted IH-mediated increases in FFA (P < 0.01). In adipose tissue, bosentan had no effect on cellular receptors and proteins involved in lipolysis (P > 0.05). ET-1 treatment did not directly induce lipolysis in differentiated HWP. In conclusion, IH increases plasma ET-1 and FFA concentrations. Inhibition of ET-1 receptors with bosentan attenuates the FFA increase in response to IH. Based on a lack of a direct effect of ET-1 in HWP, we speculate the effect of bosentan on circulating FFA in vivo may be secondary to its ability to reduce sympathoadrenal tone. [ABSTRACT FROM AUTHOR]

The article describes a clinical case of a 37-year-old patient with pulmonary capillary hemangiomatosis of functional class IV according to the WHO classification with difficulties of diagnostic search and features of PAH-specific therapy.Pulmonary arterial hypertension - group 1 in the clinical classification is represented by several forms of pathology, including very rare diseases such as pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis.The difficulties of diagnostic search consist in the absence of specific symptoms, a variety of interstitial or focal changes according to spiral computed tomography, and the final diagnosis can be made only after performing a lung biopsy, which is associated with a high risk of possible complications. During the initial treatment and examination of the patient, clinical and hemodynamic parameters did not immediately allow to suspect the presence of pulmonary capillary hemangiomatosis. And only the difficulties of the patient’s management associated with the lack of the expected effect of the therapy with PAH-specific drugs served as the basis for further diagnostic search.Against the background of taking vasodilators, with the normalization of hemodynamic parameters, the progression of respiratory and right ventricular insufficiency was noted in the patient. According to the results of an additional examination, a diagnosis of pulmonary capillary hemangiomatosis was established, therapy was corrected and further tactics of management and treatment of the patient were determined. Currently, the patient is awaiting transplantation at V.I. Shumakov national medical research center and receives specific therapy with riociguate 2.5 mg TID and bosentan 125 mg BID.

Eisenmenger syndrome (ES) refers to congenital heart diseases (CHD) with reversal flow associated with increased pulmonary pressure and irreversible pulmonary vascular remodeling. Previous reports showed limited therapeutic strategies in ES. In this study, 5 ES patients (2 males and 3 females), who had been followed regularly at our institution from 2010 to 2019, were retrospectively reviewed. We adopted an add-on combination of sildenafil, bosentan, and iloprost and collected the clinical characteristics and outcomes as well as findings of echocardiography, computed tomography, pulmonary perfusion-ventilation scans, positron emission tomography, and biomarkers. The age of diagnosis in these ES patients ranged from 23 to 54 years (38.2 ± 11.1 years; mean ± standard deviation), and they were followed for 7 to 17 years. Their mean pulmonary arterial pressure and pulmonary vascular resistance index were 56.4 ± 11.3 mmHg and 24.7 ± 8.5 WU.m2, respectively. Intrapulmonary arterial thrombosis was found in 4 patients, ischemic stroke was noted in 2 patients, and increased glucose uptake of the right ventricle was observed in 4 patients. No patient mortality was seen within 5 years of follow-up. Subsequently, 2 patients died of right ventricular failure, 1 died of sepsis related to brain abscess, and another died of sudden death. The life span of these patients was 44–62 years. Although these patients showed longer survival, the beneficial data on specific-target pharmacologic interventions in ES is still preliminary. Thus, larger trials are warranted, and the study of cardiac remodeling in ES from various CHD should be explored. [ABSTRACT FROM AUTHOR]

Introduction: Quantitative information on disposition of maternal medicines in human milk remains a major knowledge gap. This case report presents the clinical and pharmacokinetic data of a single mother-infant pair exposed to bosentan and sildenafil for the treatment of pulmonary arterial hypertension (PAH) during lactation. Case presentation: A 43-year old mother was treated with sildenafil (20 mg, 3x/day) and bosentan (125 mg, 2x/day) for PAH. Her 21-months old infant received breastfeeding in combination with adequate complementary foods. Milk samples were collected over 24 h, at day 637 and 651 after delivery. The observed average steady-state concentrations of sildenafil (2.84 μg/L) and bosentan (49.0 μg/L) in human milk were low. The Daily Infant Dosage ingested by the nursing infant through human milk was 0.02 μg/kg/day for sildenafil and 0.29 μg/kg/day for bosentan at day 637, and 0.03 μg/kg/day and 0.60 μg/kg/day at day 651. The Relative Infant Dose calculated for an exclusively breastfed infant with an estimated milk intake of 150 ml/kg/day, was 0.06% for sildenafil and 0.24% for bosentan. General health outcome of the infant, reported by the mother, was uneventful until the sampling days. Conclusion: Low medicine concentrations were found in human milk expressed 21 months after delivery after maternal intake of 20 mg sildenafil three times daily and 125 mg bosentan twice daily. General health of the nursing infant until sampling was reported as optimal by the mother. [ABSTRACT FROM AUTHOR]

Increased adiposity is associated with dysregulation of the endothelin system, both of which increase the risk of cardiovascular disease (CVD). Preclinical data indicate that endothelin dysregulation also reduces resting energy expenditure (REE). The objective was to test the hypothesis that endothelin receptor antagonism will increase REE in people with obesity compared with healthy weight individuals. Using a double blind, placebo-controlled, crossover design, 32 participants [healthy weight (HW): n = 16, BMI: 21.3 ± 2.8 kg/m², age: 26 ± 7 yr and overweight/obese (OB): n = 16, BMI: 33.5±9.5 kg/m², age: 31 ± 6 yr] were randomized to receive either 125 mg of bosentan (ETA/B antagonism) or placebo twice per day for 3 days. Breath-by-breath gas exchange data were collected and REE was assessed by indirect calorimetry. Venous blood samples were analyzed for concentrations of endothelin-1 (ET-1). Treatment with bosentan increased plasma ET-1 in both OB and HW groups. Within the OB group, the changes in absolute REE (PLA: -77.6 ± 127.6 vs. BOS: 72.2 ± 146.6 kcal/day; P = 0.046). The change in REE was not different following either treatment in the HW group. Overall, absolute plasma concentrations of ET-1 following treatment with bosentan were significantly associated with kcal/day of fat (r = 0.488, P = 0.005), percentage of fat utilization (r = 0.415, P = 0.020), and inversely associated with the percentage of carbohydrates (r = -0.419, P = 0.019), and respiratory exchange ratio (r = -0.407, P = 0.023). Taken together, these results suggest that modulation of the endothelin system may represent a novel therapeutic approach to increase both resting metabolism and caloric expenditure, and reduce CVD risk in people with increased adiposity. [ABSTRACT FROM AUTHOR]

Objective(s): We examined the antiosteoporotic effect of bosentan (Bose) by radiographic, histopathological, and molecular methods.Materials and Methods: Rats were divided into 4 groups of 8 rats each: one control (Sham), one osteoporosis only (OP), and two osteoporosis groups treated with Bose doses of 50 and 100 mg/kg (OP+Bose50, OP+Bose100). Six weeks later, Bose was administered for eight weeks to animals undergoing ovariectomy. The left femoral bone of the rats was evaluated in vitro after surgical removal. Bone mineral density (BMD) was analyzed by Dual-energy X-ray absorptiometry (DEXA). Endothelin 1 (ET-1), ET-A, and ET-B expressions were examined by real-time polymerase chain reaction (real time-PCR). In addition, bone tissue was evaluated histopathologically.Results: Compared with the osteoporosıs group, Bose significantly increased BMD values at both 50 and 100 mg/kg doses. ET-1 mRNA levels were significantly higher in the OP group than in the Sham group, while ET-1 mRNA levels were significantly lower in Bose treatment groups. ET-A mRNA levels were significantly lower in the OP group than in the Sham group, while ET-A mRNA levels were significantly higher in Bose treatment groups. Histopathological results supported the molecular results. Conclusion: Our study is the first to demonstrate the molecular, radiological, and histopathological effects of Bose in preventing osteoporosis in rats.

Introduction: Quantitative information on disposition of maternal medicines in human milk remains a major knowledge gap. This case report presents the clinical and pharmacokinetic data of a single mother-infant pair exposed to bosentan and sildenafil for the treatment of pulmonary arterial hypertension (PAH) during lactation.Case presentation: A 43-year old mother was treated with sildenafil (20 mg, 3x/day) and bosentan (125 mg, 2x/day) for PAH. Her 21-months old infant received breastfeeding in combination with adequate complementary foods. Milk samples were collected over 24 h, at day 637 and 651 after delivery. The observed average steady-state concentrations of sildenafil (2.84 μg/L) and bosentan (49.0 μg/L) in human milk were low. The Daily Infant Dosage ingested by the nursing infant through human milk was 0.02 μg/kg/day for sildenafil and 0.29 μg/kg/day for bosentan at day 637, and 0.03 μg/kg/day and 0.60 μg/kg/day at day 651. The Relative Infant Dose calculated for an exclusively breastfed infant with an estimated milk intake of 150 ml/kg/day, was 0.06% for sildenafil and 0.24% for bosentan. General health outcome of the infant, reported by the mother, was uneventful until the sampling days.Conclusion: Low medicine concentrations were found in human milk expressed 21 months after delivery after maternal intake of 20 mg sildenafil three times daily and 125 mg bosentan twice daily. General health of the nursing infant until sampling was reported as optimal by the mother.

Copyright of Farmacia is the property of Societatea de Stiinte Farmaceutice Romania and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Even though pulmonary arterial hypertension (PAH) remains an incurable disease, the combination of PAH‐specific therapies allowed treatment strategies to evolve from symptom-based ones to others that aim to move patients to low‐risk conditions. Endothelin‐1 (ET‐1) receptor antagonists emerged as specific‐PAH drugs that can be used in combination with other specific therapies. This work aimed to perform a prospective clinical assessment of patients with PAH that switched from bosentan to macitentan (POTENT), due to inadequate response. POTENT is a prospective, open‐label, single‐arm, uncontrolled study including PAH patients from our ongoing SAUDIPH registry. It enrolled 50 PAH patients divided as follows: idiopathic/heritable pulmonary arterial hypertension (I/HPAH); n = 24; PAH associated with congenital heart disease, n = 19; PAH associated with connective tissue diseases, n = 5; and pulmonary veno‐occlusive disease and/or pulmonary capillary haemangiomatosis (PVOD/ PCH), n = 2. At baseline, most patients were in World Health Organization Functional Class (WHO FC) II/III (52.0%). After switching to macitentan, patients were more likely to be in WHO FC I/II (78%) and 22% of the overall cohort moved to a lower risk condition, with three low risk stratification parameters. Mean 6‐min walking distance increased about 34m after 12 months, with a significant mean change over time (12.63 ± 11.69 at month 3 vs. 40.75 ± 12.57 at month 12, p = 0.002). Most haemodynamic parameters decreased over time, with corresponding negative mean changes (p<0.001). The safety of macitentan was confirmed by the absence of anaemia and liver injury; clinical worsening was observed only in a small group of patients. In general, macitentan might be a valid alternative to bosentan in PAH stable patients on combination therapy with insufficient clinical response, and presenting intermediate and high‐risk parameters. We anticipate that studying this strategy in PAH subgroups would further clarify its potential and limitations. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Contemporary Pediatrics is the property of Xiangya Medical Periodical Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Even though pulmonary arterial hypertension (PAH) remains an incurable disease, the combination of PAH‐specific therapies allowed treatment strategies to evolve from symptom‐based ones to others that aim to move patients to low‐risk conditions. Endothelin‐1 (ET‐1) receptor antagonists emerged as specific‐PAH drugs that can be used in combination with other specific therapies. This work aimed to perform a prospective clinical assessment of patients with PAH that switched from bosentan to macitentan (POTENT), due to inadequate response. POTENT is a prospective, open‐label, single‐arm, uncontrolled study including PAH patients from our ongoing SAUDIPH registry. It enrolled 50 PAH patients divided as follows: idiopathic/heritable pulmonary arterial hypertension (I/HPAH); n = 24; PAH associated with congenital heart disease, n = 19; PAH associated with connective tissue diseases, n = 5; and pulmonary veno‐occlusive disease and/or pulmonary capillary haemangiomatosis (PVOD/PCH), n = 2. At baseline, most patients were in World Health Organization Functional Class (WHO FC) II/III (52.0%). After switching to macitentan, patients were more likely to be in WHO FC I/II (78%) and 22% of the overall cohort moved to a lower risk condition, with three low risk stratification parameters. Mean 6‐min walking distance increased about 34 m after 12 months, with a significant mean change over time (12.63 ± 11.69 at month 3 vs. 40.75 ± 12.57 at month 12, p = 0.002). Most haemodynamic parameters decreased over time, with corresponding negative mean changes (p

Obesity is associated with dysregulation of the endothelin system. In individuals with obesity, an exaggerated pressor response to acute stress is accompanied by increased circulating endothelin-1 (ET-1). The impact of combined endothelin A/B receptor (ETA/B) antagonism on the stress-induced pressor response in overweight/obese (OB) individuals is unknown. The objective of this study is to test the hypothesis that treatment with an ETA/B antagonist (bosentan) would reduce the stress-induced pressor response and arterial stiffness in overweight/obese compared with normal weight (NW) individuals. Forty participants [normal weight (NW): n = 20, body mass index (BMI): 21.7 ± 2.4 kg/m² and overweight/obese (OB): n = 20, BMI: 33.8 ± 8.2 kg/m² ] were randomized to placebo or 125 mg of bosentan twice a day (250 mg total) for 3 days. Hemodynamics were assessed before, during, and after a cold pressor test (CPT). Endothelin-1 was assessed at baseline and immediately after CPT. Following a washout period, the same protocol was repeated with the opposite treatment. The change from baseline in mean arterial pressure (MAP) during CPT following bosentan was significantly lower (P = 0.039) in the OB group than in the NW group (OB: 28 ± 12 vs. NW: 34 ± 15 mmHg). These results suggest that ETA/B antagonism favorably blunts the pressor response to acute stress in overweight/obese individuals. [ABSTRACT FROM AUTHOR]

Copyright of Al-Mustansiriyah Journal for Pharmaceutical Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To study the efficacy of bosentan combined with sildenafil in the treatment of severe pulmonary hypertension (PH), and its impact on cardiac function. Methods: In total, 90 severe PH patients treated in The First Affiliated Hospital of Harbin Medical University, Harbin, China between November 2018 and November 2019 were included and equally assigned to two groups (A and B). Group A was treated with bosentan combined with sildenafil, while group B received conventional treatment, viz, deslanoside injection followed later by 40 mg furosemide intravenous injection. Clinical efficacy, sleep quality, psychological status, and cardiac function for the two groups were compared. Results: Group A had significantly higher effectiveness than group B before treatment (p < 0.05). Similar Pittsburgh Sleep Quality Index (PSQI) scores before treatment between the two groups were found (p > 0.05). After treatment, group A had a lower PSQI score than group B (p < 0.001). Also, following treatment, group A had more level I patients and fewer level III patients than group B (p < 0.05). The Beck depression rating scale (BDI) scores at T0 and T1 were similar for the two groups (p > 0.05). Lower post-treatment BDI scores in group A at T2 and T3, than in group B were observed (p < 0.001). In contrast to the conventional treatment group, group A had a higher cardiac output and higher cardiac index, lower systemic arterial pressure, and lower incidence of adverse reactions (p < 0.05). Conclusion: Bosentan combined with sildenafil produces higher therapeutic effects on severe PH patients than conventional treatment. [ABSTRACT FROM AUTHOR]

Endothelin-1 (ET-1) has been implicated in the pathogenesis of cardiac fibrosis. Stimulation of endothelin receptors (ETR) with ET-1 leads to fibroblast activation and myofibroblast differentiation, which is mainly characterized by an overexpression of α-smooth muscle actin (α-SMA) and collagens. Although ET-1 is a potent profibrotic mediator, the signal transductions and subtype specificity of ETR contributing to cell proliferation, as well as α-SMA and collagen I synthesis in human cardiac fibroblasts are not well clarified. This study aimed to evaluate the subtype specificity and signal transduction of ETR on fibroblast activation and myofibroblast differentiation. Treatment with ET-1 induced fibroblast proliferation, and synthesis of myofibroblast markers, α-SMA, and collagen I through the ETAR subtype. Inhibition of Gαq protein, not Gαi or Gβγ, inhibited these effects of ET-1, indicating the essential role of Gαq protein-mediated ETAR signaling. In addition, ERK1/2 was required for ETAR/Gαq axis-induced proliferative capacity and overexpression of these myofibroblast markers. Antagonism of ETR with ETR antagonists (ERAs), ambrisentan and bosentan, inhibited ET-1-induced cell proliferation and synthesis of α-SMA and collagen I. Furthermore, ambrisentan and bosentan promoted the reversal of myofibroblasts after day 3 of treatment, with loss of proliferative ability and a reduction in α-SMA synthesis, confirming the restorative effects of ERAs. This novel work reports on the ETAR/Gαq/ERK signaling pathway for ET-1 actions and blockade of ETR signaling with ERAs, representing a promising therapeutic strategy for prevention and restoration of ET-1-induced cardiac fibrosis.

Materials and Methods: The aim of the present systematic review and meta-analysis was to evaluate the therapeutic efficacy of bosentan, a dual endothelin receptor antagonist, for systemic sclerosis (SSc) patients with digital ulcers (DUs). Methods: A systematic search of MEDLINE, Embase, Web of Science, and Scopus was done using appropriate keywords till September 2021. Weighted mean difference (WMD) as the effect of therapeutic efficacy of bosentan on continuous outcomes was an estimate. Furthermore, the pooled prevalence of diffuse SSc and limited SSc was computed. Fixed or random effects models when appropriate were used for data synthesis. Results: Totally, 469 patients, with a mean age ranging from 48.1 to 63.7 years, from 8 studies were included in the systematic review and meta-analysis. The pooled frequency of diffuse SSc and limited SSc was 56% (95% confidence interval [CI]: 39%, 73%) and 44% (95% CI: 27%, 61%). The pooled prevalence of new DUs following bosentan treatment was 21% (95% CI: 10%, 33%). The results of the meta-analysis showed a pooled mean decrease of WMD: −0.09 (95% CI: −0.020, 0.02, P= 0.10), WMD: −2.82 (95% CI: −5.91, 0.27, P= 0.07), and WMD: −6.65 (95% CI: −9.49, −3.82, P< 0.001) in mean SSc-Health Assessment Questionnaire, pain, and Rodnan score, respectively. Our meta-analysis also indicated a significant pooled decrease in the number of new DUs in SSc patients compared to placebo subjects (WMD: −0.89 [95% CI: −1.40, −0.37; P= 0.001]) and baseline values (WMD: −1.34 (95% CI: −1.95, −0.73; P< 0.001). Conclusion: Bosentan possibly is an efficacious treatment option for SSc-related DUs. Although further large-scale randomized clinical trials are required to confirm the preliminary finding and underlying mechanisms of action.

Open in new tab Download slide Open in new tab Download slide OBJECTIVES Some patients present with excessive pulmonary hypertension (PH) prior to pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH). This study was performed to evaluate the clinical role of pretreatment before PEA in CTEPH patients. METHODS A total of 370 patients with CTEPH undergoing first PEA between 2003 and 2017 were divided into those receiving pretreatment with bosentan (group B: n  =   119) and those without targeted pretreatment for PH (group C: n  =   251). After selecting patients given bosentan (2–8 months) and using propensity score matching, comparable patient cohorts (n  =   23 each) were created from both groups. PEA was performed in the standard manner, and the median number of extracted segments was 14. RESULTS There were no significant differences in perioperative demographic characteristics or 30-day mortality (overall 5.7%) between the groups before and after matching. In patients with preoperative pulmonary vascular resistance (PVR) ≥800 dynes s/cm5, a significantly larger decrease in PVR was found in group B (78%) compared to group C (68%) (P  =   0.033). There was no significant difference in late survival between the groups after matching. The frequency of residual/persistent PH (mean pulmonary artery pressure >25 mmHg) was lower in group B than in group C, although the difference was not significant (22% vs 39%, respectively, P  =   0.200). Advanced age and longer cardiopulmonary bypass time were independent predictors of both 30-day mortality and residual/persistent PH (odds ratio: age, 1.053, 1.013, cardiopulmonary bypass time, 1.065, 1.010, respectively). CONCLUSIONS Preoperative treatment of CTEPH patients with bosentan for 2–8 months can improve post-PEA PVR without adverse clinical events in patients with a high preoperative PVR. A temporary bridging regime appears beneficial in selected patients prior to PEA. [ABSTRACT FROM AUTHOR]

Although there are rapid developments in molecular science and synthetic chemistry for investigation of many essential drug molecules, poor solubility and bioavailability issues are major constraint in the design of more efficient formulations. This research study focuses on the enhancement of solubility and development of the bucco-adhesive drug delivery system of bosentan using Soluplus® (polyvinyl-caprolactam-polyvinyl-acetate-polyethylene glycol graft co-polymer) as a carrier. A 32-factorial design was implemented to develop bucco-adhesive tablets using hydroxypropyl methyl cellulose (HPMC) K100 LV (X1) and Carbopol 934 P (X2) as independent variables at various levels whereas t50%(Y1) (time required to release 50% of drug), Rel4h (Y2) (percentage of the drug release in 4 h) and bio-adhesive strength (Y3) were considered as set response parameters. The positive effect of the surface response quadratic model demonstrated the change in the already set dependent variables of t50%, Rel4h and bio-adhesive strength. The FT-IR study confirmed the suitability of all the components used in the design of formulation. DSC and XRD study have confirmed the encapsulation of bosentan in the Soluplus® carrier and amorphous form of bosentan, respectively. Overall, 6.832-fold increase in solubility was observed for bosentan-solid dispersion. High-water uptake and swelling of bucco-adhesive tablets (containing bosentan-solid dispersion) was observed due to presence of the highly hydrophilic-Soluplus®. Rel4hwas found to be 97.86 ± 0.57% for optimized formulation (F4) and was decreased with increasing polymer content. The values of t50% were found to be enhanced from 1.11 to 2.32 h at the lower to higher levels of both the polymers respectively. [ABSTRACT FROM AUTHOR]