Long-term safety and tolerability of ambrisentan treatment for pediatric patients with pulmonary arterial hypertension: An open-label extension study

This open-label, extension study assessed long-term safety, tolerability, and efficacy of ambrisentan in a pediatric population (age 8- < 18 years) with pulmonary arterial hypertension (PAH). Following completion of a 6-month, randomized study, participants entered the long-term extension at individualized ambrisentan dosages (2.5/5/7.5 or 10 mg/day). Safety assessments included adverse events (AEs), AEs of special interest, and serious AEs (SAEs); efficacy outcomes included 6-min walking distance (6MWD) and World Health Organization functional class (WHO FC). Thirty-eight of 41 (93%) randomized study participants entered the extension; 21 (55%) completed (reaching age 18 years). Most participants received concomitant phosphodiesterase-5 inhibitors (n = 25/38, 66%). Median ambrisentan exposure was 3.5 years. Most participants experienced ≥ 1 AE (n = 34/38, 89%), and 21 (55%) experienced SAEs, most commonly worsening PAH (n = 3/38, 8%), acute cardiac failure, pneumonia, or anemia (n = 2/38; 5% each); none considered ambrisentan-related. Seven participants (18%) died, with recorded reasons (MedDRA preferred term): cardiac failure (n = 2), PAH (n = 2), COVID-19 (n = 1), acute right ventricular failure (n = 1), and failure to thrive (n = 1); median time to death: 5.2 years. Anemia and hepatotoxicity AEs were generally mild to moderate and did not require ambrisentan dose adjustment. Assessed at study end in 29 participants (76%), mean 6MWD improved by 17% (standard deviation: 34.3%), and all (29/29, 100%) had improved or unchanged WHO FC.    Conclusion: Long-term weight-based ambrisentan dosing, alone or combined with other PAH therapies in children with PAH aged 8- < 18 years, exhibited tolerability and clinical improvements consistent with prior randomized study results.    Trial registration: NCT01342952, April 27, 2011. What is Known: • The endothelin receptor antagonist, ambrisentan, is indicated for treatment of pulmonary arterial hypertension (PAH). Previous studies have shown similar efficacy and tolerability in pediatric patients as in adults. What is New: • This open-label extension study assessed the long-term use of ambrisentan in pediatric patients (8-<18 years) with PAH, most of whom were also receiving recommended background PAH treatment. • Weight-based dosing of ambrisentan, given alone or in combination with other PAH therapies, was well tolerated with clinical improvements consistent with prior randomized study results.

INSIGHT 2: a phase II study of tepotinib plus osimertinib in MET-amplified NSCLC and first-line osimertinib resistance

MET amplification (METamp), a mechanism of acquired resistance to EGFR tyrosine kinase inhibitors, occurs in up to 30% of patients with non-small-cell lung cancer (NSCLC) progressing on first-line osimertinib. Combining osimertinib with a MET inhibitor, such as tepotinib, an oral, highly selective, potent MET tyrosine kinase inhibitor, may overcome METamp-driven resistance. INSIGHT 2 (NCT03940703), an international, open-label, multicenter phase II trial, assesses tepotinib plus osimertinib in patients with advanced/metastatic EGFR-mutant NSCLC and acquired resistance to first-line osimertinib and METamp, determined centrally by fluorescence in situ hybridization (gene copy number ≥5 and/or MET/CEP7 ≥2) at time of progression. Patients will receive tepotinib 500 mg (450 mg active moiety) plus osimertinib 80 mg once-a-day. The primary end point is objective response, and secondary end points include duration of response, progression-free survival, overall survival and safety. Trial registration number: NCT03940703 (clinicaltrials.gov).

Serial evaluation of the pharmacokinetics of ponatinib in patients with CML and Ph + ALL

Although tyrosine kinase inhibitors (TKIs) play a crucial role in the treatment of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL), intolerance and resistance to TKIs have been serious problems. Due to a lack of research, the importance of the pharmacokinetics (PK) of TKIs is currently unclear. We examined the PK of the third-generation TKI ponatinib to monitor side effects and efficacy during treatments for one patient with CML-chronic phase (CP-CML) and two who received allogeneic hematopoietic stem cell transplantation (allo-HSCT), one for CML-blastic crisis (BC-CML) and one for Ph + ALL. The patient with CP-CML was intolerant to multiple TKIs (dasatinib, nilotinib, imatinib, and bosutinib) and thus was switched to ponatinib (15 mg/day). The patients who received allo-HSCT for BC-CML and Ph + ALL received ponatinib (15 mg/day) as maintenance therapy. Notably, serial evaluation of the PK of ponatinib showed that the median trough values (ng/ml) were 17.2 (12.2-34.5), 33.1 (21.2-40.3) and 27.7 (13.6-29.9) in patients 1, 2, and 3, respectively. These values were around the target concentration (23 ng/ml). All patients are maintaining complete remission without side effects. In conclusion, serial evaluation of PK of ponatinib may yield meaningful information about its safety and efficacy.

Lateral hypothalamus involvement in control of stress response by bed nucleus of the stria terminalis endocannabinoid neurotransmission in male rats

The endocannabinoid neurotransmission acting via local CB1 receptor in the bed nucleus of the stria terminalis (BNST) has been implicated in behavioral and physiological responses to emotional stress. However, the neural network related to this control is poorly understood. In this sense, the lateral hypothalamus (LH) is involved in stress responses, and BNST GABAergic neurons densely innervate this hypothalamic nucleus. However, a role of BNST projections to the LH in physiological responses to stress is unknown. Therefore, using male rats, we investigated the role of LH GABAergic neurotransmission in the regulation of cardiovascular responses to stress by CB1 receptors within the BNST. We observed that microinjection of the selective CB1 receptor antagonist AM251 into the BNST decreased the number of Fos-immunoreactive cells within the LH of rats submitted to acute restraint stress. Treatment of the BNST with AM251 also enhanced restraint-evoked tachycardia. Nevertheless, arterial pressure increase and sympathetically-mediated cutaneous vasoconstriction to restraint was not affected by CB1 receptor antagonism within the BNST. The effect of AM251 in the BNST on restraint-evoked tachycardia was abolished in animals pretreated with the selective GABAA receptor antagonist SR95531 in the LH. These results indicate that regulation of cardiovascular responses to stress by CB1 receptors in the BNST is mediated by GABAergic neurotransmission in the LH. Present data also provide evidence of the BNST endocannabinoid neurotransmission as a mechanism involved in LH neuronal activation during stressful events.

Phase 1b/2 trial of tepotinib in sorafenib pretreated advanced hepatocellular carcinoma with MET overexpression

BACKGROUND

This Phase 1b/2 study evaluated tepotinib, a highly selective MET inhibitor, in US/European patients with sorafenib pretreated advanced hepatocellular carcinoma (aHCC) with MET overexpression.

METHODS

Eligible adults had aHCC, progression after ≥4 weeks of sorafenib, and, for Phase 2 only, MET overexpression. Tepotinib was administered once daily at 300 or 500 mg in Phase 1b ('3 + 3' design), and at the recommended Phase 2 dose (RP2D) in Phase 2. Primary endpoints were dose-liming toxicities (DLTs; Phase 1b) and 12-week investigator-assessed progression-free survival (PFS; Phase 2).

RESULTS

In Phase 1b (n = 17), no DLTs occurred and the RP2D was confirmed as 500 mg. In Phase 2 (n = 49), the primary endpoint was met: 12-week PFS was 63.3% (90% CI: 50.5-74.7), which was significantly greater than the predefined null hypothesis of ≤15% (one-sided binomial exact test: P < 0.0001). Median time to progression was 4 months. In Phase 2, 28.6% of patients had treatment-related Grade ≥3 adverse events, including peripheral oedema and lipase increase (both 6.1%).

CONCLUSIONS

Tepotinib was generally well tolerated and the RP2D (500 mg) showed promising efficacy and, therefore, a positive benefit-risk balance in sorafenib pretreated aHCC with MET overexpression.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02115373.

Dysregulation of Pyruvate Kinase M2 Promotes Inflammation in a Mouse Model of Obese Allergic Asthma

Obesity is a risk factor for the development of asthma and represents a difficult-to-treat disease phenotype. Aerobic glycolysis is emerging as a key feature of asthma, and changes in glucose metabolism are linked to leukocyte activation and adaptation to oxidative stress. Dysregulation of PKM2 (pyruvate kinase M2), the enzyme that catalyzes the last step of glycolysis, contributes to house dust mite (HDM)-induced airway inflammation and remodeling in lean mice. It remains unclear whether glycolytic reprogramming and dysregulation of PKM2 also contribute to obese asthma. The goal of the present study was to elucidate the functional role of PKM2 in a murine model of obese allergic asthma. We evaluated the small molecule activator of PKM2, TEPP46, and assessed the role of PKM2 using conditional ablation of the Pkm2 allele from airway epithelial cells. In obese C57BL/6NJ mice, parameters indicative of glycolytic reprogramming remained unchanged in the absence of stimulation with HDM. Obese mice that were subjected to HDM showed evidence of glycolytic reprogramming, and treatment with TEPP46 diminished airway inflammation, whereas parameters of airway remodeling were unaffected. Epithelial ablation of Pkm2 decreased central airway resistance in both lean and obese allergic mice in addition to decreasing inflammatory cytokines in the lung tissue. Lastly, we highlight a novel role for PKM2 in the regulation of glutathione-dependent protein oxidation in the lung tissue of obese allergic mice via a putative IFN-γ-glutaredoxin1 pathway. Overall, targeting metabolism and protein oxidation may be a novel treatment strategy for obese allergic asthma.

Venoocclusive Disease With Both Hepatic and Pulmonary Involvement

Pulmonary venoocclusive disease (PVOD) is a rare form of pulmonary vascular disease with pulmonary hypertension characterized by preferential involvement of the pulmonary venous system. Hepatic venoocclusive disease (HVOD), also known as sinusoidal obstruction syndrome, is a condition that occurs in 13% to 15% of patients after hematopoietic stem cell transplantation (HSCT). Although hepatic and pulmonary venoocclusive diseases may share some pathologic features as well as some etiologies such as HSCT, these two disorders have never been described together in a single adult patient. We report the case of a patient who received HSCT and developed HVOD and PVOD within 9 months. Despite their differences, PVOD and HVOD share common risk factors and associated conditions, suggesting that in the context of HSCT, the two diseases share common pathophysiological mechanisms. Optimal treatment for HSCT-related PVOD remains to be determined.

Tepotinib Inhibits the Epithelial-Mesenchymal Transition and Tumor Growth of Gastric Cancers by Increasing GSK3β, E-Cadherin, and Mucin 5AC and 6 Levels

Aberrant expression of mucins (MUCs) can promote the epithelial–mesenchymal transition (EMT), which leads to enhanced tumorigenesis. Carcinogenesis-related pathways involving c-MET and β-catenin are associated with MUCs. In this study, we characterized the expression of EMT-relevant proteins including MET, β-catenin, and E-cadherin in human gastric cancer (GC) cell lines, and further characterized the differential susceptibility of these cell lines compared with the c-MET inhibitor tepotinib. We assessed the antitumor activity of tepotinib in GC cell lines. The effects of tepotinib on cell viability, apoptotic cell death, EMT, and c-MET and β-catenin signaling were evaluated by 3-(4,5 dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl)-2H-tetrazolium (MTS), flow cytometry, Western blotting, and qRT-PCR. The antitumor efficacy was assessed in MKN45 xenograft mice. Tepotinib treatment induced apoptosis in c-MET-amplified SNU620, MKN45, and KATO III cells, but had no effect on c-MET-reduced MKN28 or AGS cells. Tepotinib treatment also significantly reduced the protein levels of phosphorylated and total c-MET, phosphorylated and total ERK, β-catenin, and c-MYC in SNU620 and MKN45 cells. In contrast, this drug was only slightly active against KATO III cells. Notably, tepotinib significantly reduced the expression of EMT-promoting genes such as MMP7, COX-2, WNT1, MUC5B, and c-MYC in c-MET-amplified GC cells and increased the expression of EMT-suppressing genes such as MUC5AC, MUC6, GSK3β, and E-cadherin. In a mouse model, tepotinib exhibited good antitumor growth activity along with increased E-cadherin and decreased phosphorylated c-MET (phospho-c-MET) protein levels. Collectively, these results suggest that tepotinib suppresses tumor growth and migration by negatively regulating c-MET-induced EMT. These findings provide new insights into the mechanism by which MUC5AC and MUC6 contribute to GC progression.

A novel BMPR2 mutation in a patient with heritable pulmonary arterial hypertension and suspected hereditary hemorrhagic telangiectasia: A case report

RATIONALE

BMPR2 mutation is the most common cause of heritable pulmonary arterial hypertension (HPAH), but rare in hereditary hemorrhagic telangiectasia (HHT). ACVRL1, ENG and SMAD4 are the most common gene mutations reported in HPAH with HHT.

PATIENT CONCERNS

We report a 11-year-old boy with a definite diagnosis of pulmonary hypertension and suspected HHT with recurrent epistaxis. The results of gene detection showed that there was a nosense mutation in BMPR2. The results of gene detection of ACVRL1, ENG and SMAD4 were normal.

DIAGNOSES

Heritable pulmonary arterial hypertension with suspected hereditary hemorrhagic telangiectasia.

INTERVENTIONS

Patient was treated with ambrisentan 2.5 mg qd. About a month later, the patient developed massive gastrointestinal bleeding and sudden convulsions. The patient's vital signs were stable after symptomatic treatment.

OUTCOMES

After discharging from hospital, the patients continued to take ambrisentan. No epistaxis or gastrointestinal bleeding was found in one month of follow-up, but the symptoms of chest tightness were not significantly alleviated.

LESSONS

BMPR2 with a nonsense mutation is more likely to cause HPAH with HHT and are more likely to be life-threatening.

Initial combination therapy of ambrisentan and tadalafil in connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH) in the modified intention-to-treat population of the AMBITION study: post hoc analysis

OBJECTIVES

To evaluate initial combination therapy with ambrisentan plus tadalafil (COMB) compared with monotherapy of either agent (MONO), and the utility of baseline characteristics and risk stratification in predicting outcomes, in patients with connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH) and the systemic sclerosis (SSc)-pulmonary arterial hypertension (PAH) subpopulation.

METHODS

This post hoc analysis of the Ambrisentan and Tadalafil in Patients with Pulmonary Arterial Hypertension (AMBITION) study included patients with CTD-PAH from the modified intention-to-treat population. Time to clinical failure (TtCF) was assessed by baseline characteristics, treatment assignment and risk group (low, intermediate and high) at baseline and week 16. TtCF was compared between groups using Kaplan-Meier curves and Cox proportional hazards regression modelling.

RESULTS

The analysis included 216 patients (COMB, n=117; MONO, n=99). The risk of clinical failure was lower with COMB versus MONO (risk reduction: CTD-PAH 51.7%, SSc-PAH 53.7%), particularly in patients with haemodynamic parameters characteristic of typical PAH without features of left heart disease and/or restrictive lung disease at baseline. The risk of clinical failure was lower with COMB versus MONO in the baseline low-risk group (HR not calculated due to no events in COMB), baseline intermediate-risk group (HR 0.519, 95% CI 0.297 to 0.905) and in the week 16 low-risk group (HR 0.069, 95% CI 0.009 to 0.548).

CONCLUSIONS

The benefit of COMB over MONO was demonstrated in patients with CTD-PAH, particularly in those with typical PAH haemodynamic characteristics at baseline. COMB is appropriate for patients categorised as low risk and intermediate risk at baseline and low risk at follow-up.

TRIAL REGISTRATION NUMBER

NCT01178073.

P38α-MAPK Signaling Inhibition Attenuates Soleus Atrophy during Early Stages of Muscle Unloading

To test the hypothesis that p38α-MAPK plays a critical role in the regulation of E3 ligase expression and skeletal muscle atrophy during unloading, we used VX-745, a selective p38α inhibitor. Three groups of rats were used: non-treated control (C), 3 days of unloading/hindlimb suspension (HS), and 3 days HS with VX-745 inhibitor (HSVX; 10 mg/kg/day). Total weight of soleus muscle in HS group was reduced compared to C (72.3 ± 2.5 vs 83.0 ± 3 mg, respectively), whereas muscle weight in the HSVX group was maintained (84.2 ± 5 mg). The expression of muscle RING-finger protein-1 (MuRF1) mRNA was significantly increased in the HS group (165%), but not in the HSVX group (127%), when compared with the C group. The expression of muscle-specific E3 ubiquitin ligases muscle atrophy F-box (MAFbx) mRNA was increased in both HS and HSVX groups (294% and 271%, respectively) when compared with C group. The expression of ubiquitin mRNA was significantly higher in the HS (423%) than in the C and HSVX (200%) groups. VX-745 treatment blocked unloading-induced upregulation of calpain-1 mRNA expression (HS: 120%; HSVX: 107%). These results indicate that p38α-MAPK signaling regulates MuRF1 but not MAFbx E3 ligase expression and inhibits skeletal muscle atrophy during early stages of unloading.

Venetoclax and BCR-ABL Tyrosine Kinase Inhibitor Combinations: Outcome in Patients with Philadelphia Chromosome-Positive Advanced Myeloid Leukemias

BACKGROUND

Philadelphia chromosome-positive (Ph+) advanced leukemias, including acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) in myeloid blast phase (MBP), have poor outcomes. Venetoclax has shown synergism with BCR-ABL1 tyrosine kinase inhibitors (TKI) in preclinical studies. However, clinical activity of venetoclax and TKI-based regimens is unknown.

METHODS

We conducted a retrospective study on patients with Ph+ AML (n = 7) and CML-MBP (n = 9) who received venetoclax combined with TKI-based regimens at our institution.

RESULTS

Median patient age was 42 years, and the median number of prior therapy cycles was 5 (range 2-8). Nine patients received decitabine-based, and 7 received intensive chemotherapy-based regimens. Ten patients (63%) received ponatinib. The overall response rate (ORR) in 15 evaluable patients was 60% (1 complete remission [CR], 6 CR with incomplete hematologic recovery [CRi], 1 morphologic leukemia-free state, and 1 partial response). The ORR was 43% in Ph+ AML and 75% in CML-MBP. The median overall survival (OS) for all patients was 3.6 months, for AML OS was 2.0 months, and for CML-MBP OS was 10.9 months. The median relapse-free survival for AML and CML-MBP was 3.6 and 3.9 months, respectively. Compared to nonresponders, patients achieving CR/CRi had higher baseline Ph+ metaphases and BCR-ABL1 PCR.

CONCLUSIONS

Combination therapy of venetoclax with TKI-based regimens shows encouraging activity in very heavily pretreated, advanced Ph+ leukemias, particularly CML-MBP.

First-in-Human Studies of MW01-6-189WH, a Brain-Penetrant, Antineuroinflammatory Small-Molecule Drug Candidate: Phase 1 Safety, Tolerability, Pharmacokinetic, and Pharmacodynamic Studies in Healthy Adult Volunteers

MW01‐6‐189WH (MW189) is a novel central nervous system–penetrant small‐molecule drug candidate that selectively attenuates stressor‐induced proinflammatory cytokine overproduction and is efficacious in intracerebral hemorrhage and traumatic brain injury animal models. We report first‐in‐human, randomized, double‐blind, placebo‐controlled phase 1 studies to evaluate the safety, tolerability, and pharmacokinetics (PK) of single and multiple ascending intravenous doses of MW189 in healthy adult volunteers. MW189 was safe and well tolerated in single and multiple doses up to 0.25 mg/kg, with no clinically significant concerns. The most common drug‐related treatment‐emergent adverse event was infusion‐site reactions, likely related to drug solution acidity. No clinically concerning changes were seen in vital signs, electrocardiograms, physical or neurological examinations, or safety laboratory results. PK analysis showed dose‐proportional increases in plasma concentrations of MW189 after single or multiple doses, with approximately linear kinetics and no significant drug accumulation. Steady state was achieved by dose 3 for all dosing cohorts. A pilot pharmacodynamic study administering low‐dose endotoxin to induce a systemic inflammatory response was done to evaluate the effects of a single intravenous dose of MW189 on plasma cytokine levels. MW189 treatment resulted in lower levels of the proinflammatory cytokine TNF‐α and higher levels of the anti‐inflammatory cytokine IL‐10 compared with placebo treatment. The outcomes are consistent with the pharmacological mechanism of MW189. Overall, the safety profile, PK properties, and pharmacodynamic effect support further development of MW189 for patients with acute brain injury.

A randomized, placebo-controlled, phase 1 study to evaluate the effects of TAK-063 on ketamine-induced changes in fMRI BOLD signal in healthy subjects

RATIONALE

Phosphodiesterase 10A inhibitor TAK-063 has shown effects that suggest efficacy in schizophrenia treatment.

OBJECTIVE

This randomized, double-blind, placebo-controlled, incomplete-crossover study investigated effects of single oral administration of TAK-063 on ketamine-induced changes in blood oxygen level-dependent (BOLD) signal in healthy males.

METHODS

Healthy men aged 18 to 45 years with normal magnetic resonance imaging (MRI) scans and electroencephalogram measurements at screening were eligible. Each subject was randomized to one of nine treatment schedules: all subjects received placebo and two of three doses of TAK-063 followed by ketamine. The primary endpoint was ketamine-induced brain activity in select regions of the brain during resting state. Secondary endpoints included pharmacokinetic parameters of TAK-063, proportion of subjects with treatment-emergent adverse events (AEs), and percentage of subjects meeting criteria for abnormal safety laboratory tests and vital sign measurements.

RESULTS

The study comprised 27 subjects. Prior to ketamine infusion, TAK-063 exerted region-specific effects on resting state functional MRI (fMRI) BOLD signal. After ketamine administration, TAK-063 reduced the Cohen's effect size for resting-state fMRI BOLD signal in key brain regions examined, and exerted similar effects on BOLD signal during the working memory task across all doses. TAK-063 was safe and well tolerated.

CONCLUSIONS

Our results are consistent with non-clinical studies of ketamine and TAK-063 and clinical studies of ketamine and risperidone. It is unknown whether these data are predictive of potential antipsychotic efficacy, and further analyses are required.

BET inhibitor bromosporine enhances 5-FU effect in colorectal cancer cells

Treatment of colorectal cancer (CRC) remains a challenge because of the lack of effective early treatment strategies and high incidence of relapse. 5-Fluorouracil (5-FU) is a typical CRC treatment. Bromosporine is an innovative bromodomain and extraterminal domain (BET) inhibitor. We investigated if CRC could be targeted by the combination of 5-FU and bromosporine in a synergistic manner in vivo and in vitro. Our findings shown that the combination treatment inhibits cell viability, formation of colonies, increased apoptosis and cell cycle arrest at G0-G1. In addition, the expression level of BRD4 was high in HCT116 cells exposed to 5-FU that showed lower apoptosis against the parental cells. Moreover, the 5-FU-resistance was reversed significantly by BRD4 knockdown or inhibition. The drug combination showed increased activity against tumor than individual drug exposure in the xenograft model. In conclusion, this work serves as a basic clinical evaluation of 5-FU and bromosporine as an effective therapeutic approach for CRC.

Ponatinib in the Treatment of Chronic Myeloid Leukemia and Philadelphia Chromosome-Positive Acute Leukemia: Recommendations of a German Expert Consensus Panel with Focus on Cardiovascular Management

Treatment of chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute leukemia (Ph+ ALL) has been revolutionized with the advent of tyrosine kinase inhibitors (TKIs). Most patients with CML achieve long-term survival similar to individuals without CML due to treatment with TKIs not only in frontline but also in further lines of therapy. The third-generation TKI ponatinib has demonstrated efficacy in patients with refractory CML and Ph+ ALL. Ponatinib is currently the most potent TKI in this setting demonstrating activity against T315I mutant clones. However, ponatinib's safety data revealed a dose-dependent, increased risk of serious cardiovascular (CV) events. Guidance is needed to evaluate the benefit-risk profile of TKIs, such as ponatinib, and safety measures to prevent treatment-associated CV events. An expert panel of German hematologists and cardiologists summarize current evidence regarding ponatinib's efficacy and CV safety profile. We propose CV management strategies for patients who are candidates for ponatinib.

The oral Janus kinase/spleen tyrosine kinase inhibitor ASN002 demonstrates efficacy and improves associated systemic inflammation in patients with moderate-to-severe atopic dermatitis: results from a randomized double-blind placebo-controlled study

BACKGROUND

ASN002 is an oral dual inhibitor of Janus kinase and spleen tyrosine kinase, which are involved in the pathogenesis of atopic dermatitis (AD) through their regulatory role on T helper (Th)1, Th2 and Th17/Th22 pathways.

OBJECTIVES

The objectives of this study were to evaluate the efficacy, safety, pharmacokinetics and effects on systemic biomarkers of ASN002 in patients with moderate-to-severe AD. Methods A total of 36 patients with moderate-to-severe AD were randomized (3 : 1) to ASN002 or placebo in the phase Ib study. Three dosage cohorts were studied over a 28-day period (20 mg, 40 mg and 80 mg once daily).

RESULTS

ASN002 was superior to placebo for the proportion of patients achieving Eczema Area and Severity Index (EASI) 50 (20 mg 20%, P = 0·93; 40 mg 100%, P = 0·003; 80 mg 83%, P = 0·03; placebo 22%), EASI 75 (20 mg 0%, P = 0·27; 40 mg 71%, P = 0·06; 80 mg 33%, P = 0·65; placebo 22%) and in change from baseline in pruritus (20 mg -1·3 ± 2·1, P = 0·81; 40 mg -3·1 ± 2·7, P = 0·27; 80 mg -4·7 ± 2·1, P = 0·01; placebo -1·6 ± 1·8). Adverse events were generally mild and similar across all groups. ASN002 showed dose-dependent plasma exposure with low interpatient variability, significantly downregulated several serum biomarkers involved in Th1, Th2 and Th17/Th22 immunity, and decreased the atherosclerosis-associated biomarker E selectin/SELE.

CONCLUSIONS

In patients with moderate-to-severe AD, ASN002 showed strong efficacy with rapid onset of action and associated improvements in systemic inflammation.

Different Routes to Inhibit Fatty Acid Amide Hydrolase: Do All Roads Lead to the Same Place?

There is robust evidence indicating that enhancing the endocannabinoid (eCB) tone has therapeutic potential in several brain disorders. The inhibition of eCBs degradation by fatty acid amide hydrolase (FAAH) blockade, is the best-known option to increase N-acyl-ethanolamines-(NAEs)-mediated signaling. Here, we investigated the hypothesis that intranasal delivery is an effective route for different FAAH inhibitors, such as URB597 and PF-04457845. URB597 and PF-04457845 were subchronically administered in C57BL/6 male mice every other day for 20 days for overall 10 drug treatment, and compared for their ability to inhibit FAAH activity by the way of three different routes of administration: intranasal (i.n.), intraperitoneal (i.p.) and oral (p.o.). Lastly, we compared the efficacy of the three routes in terms of URB597-induced increase of NAEs levels in liver and in different brain areas. Results: We show that PF-04457845 potently inhibits FAAH regardless the route selected, and that URB597 was less effective in the brain after p.o. administration while reached similar effects by i.n. and i.p. routes. Intranasal URB597 delivery always increased NAEs levels in brain areas, whereas a parallel increase was not observed in the liver. By showing the efficacy of intranasal FAAH inhibition, we provide evidence that nose-to-brain delivery is a suitable alternative to enhance brain eCB tone for the treatment of neurodegenerative disorders and improve patients’ compliance.

Effects and mechanism of ensartinib (X-396) on the adhesion and metastasis of non-small cell lung cancer cells

The current study aimed to investigate the inhibitory effect and mechanism of ensartinib on adhesion, invasion and migration of non-small cell lung cancer (NSCLC) cells, including H460 and A549. Cell adhesion test, scratch test and Transwell cell invasion test were used to detect cell adhesion, migration and invasion. RT-PCR was used to detect the expression of MMP-2 and MMP-9 in H460 and A549 cells. Western blot was used to detect the expression of MMP-2 and MMP-9 proteins, ERK signaling pathway related proteins and p-Akt. Our data showed that ensartinib inhibited adhesion, invasion and migration of H460 and A549 cells in a concentration-dependent manner (P < 0.05). Ensartinib decreased the expression of MMP-2 and MMP-9 in H460 and A549 cells (P < 0.01). It also downregulated the expression of MMP-2 and MMP-9 in H460 and A549 cells, and inhibited the expression of Ras, p-c-Raf, p-ERK 1/2 and p-Akt upstream in a concentration- and time-dependent manner. Ensartinib inhibits the adhesion, invasion and migration of NSCLC cells, and such effect is related to downregulation of MMP-2 and MMP-9 expression, inhibition of ERK signaling pathway and p-Akt expression.

Third-line antiretroviral therapy in low-income and middle-income countries (ACTG A5288): a prospective strategy study

BACKGROUND

Antiretroviral therapy (ART) management is challenging for individuals in resource-limited settings presenting for third-line treatment because of complex resistance patterns, partly due to reduced access to viral load monitoring. We aimed to evaluate use of newer antiretroviral drugs and contemporary management approaches, including population-based sequencing, to select appropriate antiretrovirals, plasma viral load monitoring, and interventions to improve adherence in individuals presenting with second-line viral failure.

METHODS

A5288 was a phase 4, third-line ART strategy study done at 19 urban sites in ten countries that enrolled adult participants with confirmed plasma HIV-1 RNA (viral load) of 1000 copies per mL or more after more than 24 weeks of protease inhibitor-based second-line ART. The primary objective was to use antiretrovirals (raltegravir, etravirine, and ritonavir-boosted darunavir) and diagnostic monitoring technologies, including viral load, genotyping, and adherence support to achieve viral load suppression (defined as ≤200 copies per mL) in 65% or more of participants. ART history and real-time drug resistance genotypes were used to assign participants to one of four cohorts: cohort A (no lopinavir resistance) stayed on second-line ART and cohorts B (B1, best available nucleoside reverse transcriptase inhibitors [NRTIs] plus ritonavir-boosted darunavir plus raltegravir; B2, ritonavir-boosted darunavir plus raltegravir plus etravirine; B3, ritonavir-boosted darunavir, raltegravir, and either tenofovir plus emtricitabine or tenofovir plus lamivudine), C (ritonavir-boosted darunavir plus raltegravir plus tenofovir-emtricitabine or tenofovir plus lamivudine), and D (best available NRTIs plus ritonavir-boosted darunavir plus raltegravir) were defined by increasing levels of resistance and received appropriate regimens, including new antiretrovirals. Participants in Cohort B without detectable hepatitis B surface antigen were assigned by blocked randomisation to cohorts B1 and B2, and those with detectable hepatitis B surface antigen were assigned to cohort B3. The trial is registered with ClinicalTrials.gov, number NCT01641367.

FINDINGS

From Jan 10, 2013, to Sept 10, 2015, 545 participants were enrolled. 287 (53%) were assigned to cohort A, 74 (14%) to B1, 72 (13%) to B2, eight (1%) to B3, 70 (13%) to C, and 34 (6%) to D. Overall, 349 (64%, 95% CI 60-68) participants achieved viral suppression at week 48, with proportions varying from 125 (44%) of 287 in cohort A to 65 (88%) of 74 in cohort B1, 63 (88%) of 72 in B2, eight (100%) of eight in B3, 63 (90%) of 70 in C, and 25 (74%) of 34 in D. Participants in cohort A remained on their second-line protease inhibitor, and had the most participants with grade 3 or higher adverse events (147 [51%]).

INTERPRETATION

Targeted real-time genotyping to select third-line ART can appropriately allocate more costly antiretrovirals to those with greater levels of HIV drug resistance.

FUNDING

National Institutes of Health.

Exploring the overlapping binding sites of ifenprodil and EVT-101 in GluN2B-containing NMDA receptors using novel chicken embryo forebrain cultures and molecular modeling

N-methyl-d-aspartate receptors (NMDAR) are widely expressed in the brain. GluN2B subunit-containing NMDARs has recently attracted significant attention as potential pharmacological targets, with emphasis on the functional properties of allosteric antagonists. We used primary cultures from chicken embryo forebrain (E10), expressing native GluN2B-containing NMDA receptors as a novel model system. Comparing the inhibition of calcium influx by well-known GluN2B subunit-specific allosteric antagonists, the following rank order of potency was found: EVT-101 (EC 50 22 ± 8 nmol/L) > Ro 25-6981 (EC 50 60 ± 30 nmol/L) > ifenprodil (EC 50 100 ± 40 nmol/L) > eliprodil (EC 50 1300 ± 700 nmol/L), similar to previous observations in rat cortical cultures and cell lines overexpressing chimeric receptors. The less explored Ro 04-5595 had an EC 50 of 186 ± 32 nmol/L. Venturing to explain the differences in potency, binding properties were further studied by in silico docking and molecular dynamics simulations using x-ray crystal structures of GluN1/GluN2B amino terminal domain. We found that Ro 04-5595 was predicted to bind the recently discovered EVT-101 binding site, not the ifenprodil-binding site. The EVT-101 binding pocket appears to accommodate more structurally different ligands than the ifenprodil-binding site, and contains residues essential in ligand interactions necessary for calcium influx inhibition. For the ifenprodil site, the less effective antagonist (eliprodil) fails to interact with key residues, while in the EVT-101 pocket, difference in potency might be explained by differences in ligand-receptor interaction patterns.

The Use of the Novel Calcium Sensitizer Levosimendan in Critically Ill Patients

Levosimendan, a novel calcium sensitizer, enhances cardiac contractility by increasing myocyte sensitivity to calcium, and induces vasodilation. In this prospective observational study the haemodynamic effects of levosimendan in postoperative critically ill patients are reported. Twelve patients with the need for inotropic support were studied. One dose of levosimendan (12.5 mg) was administered at a rate of 0.1-0.2 μg.kg−1.min−1, either alone or in addition to pre-existing inotropic therapy. Haemodynamic measurements were obtained at baseline, and at 3 h, 6 h, 12 h, and 24 h after the start of the levosimendan infusion.

Levosimendan significantly increased cardiac output from (mean±SD) 4.3±0.9 l.min−1 to 5.2±1.5 l.min−1 after 24 h (P=0.013), by increases in stroke volume (baseline 47±15 ml, after 24 h 57±25 ml, P=0.05), as heart rate remained unchanged. Systemic vascular resistance decreased from 1239±430 dyn.sec.cm−5 at baseline to 963± 322 dyn.sec.cm−5 at 24 h (P<0.001). Pre-existing inotropic therapy present in ten patients remained unchanged or was reduced.

In postoperative critically ill patients, infusion of levosimendan exerted favourable haemodynamic responses. Levosimendan increased cardiac output by increasing stroke volume, which might be attributed primarily to its inotropic properties. Due to its cyclic adenosine monophosphate independent positive inotropic effects, levosimendan may be of value as adjunctive therapy to other inotropic drugs in critically ill patients.

Life after ponatinib failure: outcomes of chronic and accelerated phase CML patients who discontinued ponatinib in the salvage setting

Ponatinib is a pan-tyrosine kinase inhibitor (TKI) with efficacy in multirefractory CML patients who have failed other TKIs. Despite excellent response rates, resistance or intolerance may develop. We conducted a retrospective review of the outcome of patients with chronic (CP) and accelerated (AP) phase CML refractory to prior TKI who discontinued ponatinib for resistance or intolerance. Nineteen CP patients, discontinued due to resistance (n = 13), toxicity (n = 5) and to pursue stem cell transplantation (n = 1). At discontinuation, 14 were still in CP, three had progressed to AP and two to blast phase (BP). Three CP patients improved their cytogenetic response (CyR) to complete CyR (CCyR), two after SCT and one on omacetaxine. None of the 12 patients, without a major cytogenetic response at ponatinib discontinuation, including all patients treated with subsequent TKIs, responded to therapy. Seventeen AP patients, stopped ponatinib due to resistance (n = 15) or intolerance (n = 2). At discontinuation, 14 were still in AP and three had progressed to BP. Four patients were treated with SCT and one achieved major molecular response. None of the 12 patients treated with non-SCT approaches responded to subsequent therapy. Median survival for all patients was 16.6 months after ponatinib discontinuation (31, 9 and 13 months for patients in CP, AP and BP, respectively). Median survival was 60 months for patients who discontinued ponatinib for toxicity and 11 months for those who discontinued for resistance. Long-term outcome of patients with ponatinib failure are poor with estimated one-year OS and EFS rates of 54% and 40%, respectively. New treatment options are required for this subset of patients.

The Effect of Selective c-MET Inhibitor on Hepatocellular Carcinoma in the MET-Active, β-Catenin-Mutated Mouse Model

Simultaneous mutations in CTNNB1 and activation of c-MET occur in 9%-12.5% of patients with hepatocellular carcinoma (HCC). Coexpression of c-MET-V5 and mutant β-catenin-Myc in mouse liver by sleeping beauty transposon/transposase and hydrodynamic tail vein injection (SB-HTVI) led to the development of HCC with 70% molecular identity to the clinical subset. Using this model, we investigated the effect of EMD1214063, a highly selective c-MET inhibitor. Five weeks after SB-HTVI when tumors were established, EMD1214063 (10 mg/kg) was administered by gastric gavage as a single agent on 5-day-on/3-day-off schedule, compared to vehicle only control. Mice were harvested at 8 or 11 weeks posttreatment. Decreased p-MET, p-AKT, p-STAT3, and p-ERK proved in vivo efficacy of EMD1214063. We observed lower Ki-67, PCNA, V5-tag, and cyclin D1 after EMD1214063 treatment only at 8 weeks. Overall, no significant differences were observed in tumor burden between the groups, although EMD1214063 marginally but significantly improved overall survival by 1.5-2 weeks. Tumors remained α-fetoprotein+, did not show any differences in inflammation, and lacked fibrosis in either group. In conclusion, c-MET inhibition alone had a minor effect on Met-β-catenin HCC at the early stages of HCC development. Thus, a single therapy with the c-MET inhibitor will be insufficient for sustained response in Met-β-catenin HCC requiring assessment of additional combinations.

Targeting BCR-ABL-Independent TKI Resistance in Chronic Myeloid Leukemia by mTOR and Autophagy Inhibition

Background

Imatinib and second-generation tyrosine kinase inhibitors (TKIs) nilotinib and dasatinib have statistically significantly improved the life expectancy of chronic myeloid leukemia (CML) patients; however, resistance to TKIs remains a major clinical challenge. Although ponatinib, a third-generation TKI, improves outcomes for patients with BCR-ABL-dependent mechanisms of resistance, including the T315I mutation, a proportion of patients may have or develop BCR-ABL-independent resistance and fail ponatinib treatment. By modeling ponatinib resistance and testing samples from these CML patients, it is hoped that an alternative drug target can be identified and inhibited with a novel compound.

Methods

Two CML cell lines with acquired BCR-ABL-independent resistance were generated following culture in ponatinib. RNA sequencing and gene ontology (GO) enrichment were used to detect aberrant transcriptional response in ponatinib-resistant cells. A validated oncogene drug library was used to identify US Food and Drug Administration-approved drugs with activity against TKI-resistant cells. Validation was performed using bone marrow (BM)-derived cells from TKI-resistant patients (n = 4) and a human xenograft mouse model (n = 4-6 mice per group). All statistical tests were two-sided.

Results

We show that ponatinib-resistant CML cells can acquire BCR-ABL-independent resistance mediated through alternative activation of mTOR. Following transcriptomic analysis and drug screening, we highlight mTOR inhibition as an alternative therapeutic approach in TKI-resistant CML cells. Additionally, we show that catalytic mTOR inhibitors induce autophagy and demonstrate that genetic or pharmacological inhibition of autophagy sensitizes ponatinib-resistant CML cells to death induced by mTOR inhibition in vitro (% number of colonies of control[SD], NVP-BEZ235 vs NVP-BEZ235+HCQ: 45.0[17.9]% vs 24.0[8.4]%, P = .002) and in vivo (median survival of NVP-BEZ235- vs NVP-BEZ235+HCQ-treated mice: 38.5 days vs 47.0 days, P = .04).

Conclusion

Combined mTOR and autophagy inhibition may provide an attractive approach to target BCR-ABL-independent mechanism of resistance.

Nanoparticle-releasing nanofiber composites for enhanced in vivo vaginal retention

Current approaches for topical vaginal administration of nanoparticles result in poor retention and extensive leakage. To overcome these challenges, we developed a nanoparticle-releasing nanofiber delivery platform and evaluated its ability to improve nanoparticle retention in a murine model. We individually tailored two components of this drug delivery system for optimal interaction with mucus, designing (1) mucoadhesive fibers for better retention in the vaginal tract, and (2) PEGylated nanoparticles that diffuse quickly through mucus. We hypothesized that this novel dual-functioning (mucoadhesive/mucus-penetrating) composite material would provide enhanced retention of nanoparticles in the vaginal mucosa. Equivalent doses of fluorescent nanoparticles were vaginally administered to mice in either water (aqueous suspension) or fiber composites, and fluorescent content was quantified in cervicovaginal mucus and vaginal tissue at time points from 24 h to 7d. We also fabricated composite fibers containing etravirine-loaded nanoparticles and evaluated the pharmacokinetics over 7d. We found that our composite materials provided approximately 30-fold greater retention of nanoparticles in the reproductive tract at 24 h compared to aqueous suspensions. Compared to nanoparticles in aqueous suspension, the nanoparticles in fiber composites exhibited sustained and higher etravirine concentrations after 24 h and up to 7d, demonstrating the capabilities of this new delivery platform to sustain nanoparticle release out to 3d and drug retention out to one week after a single administration. This is the first report of nanoparticle-releasing fibers for vaginal drug delivery, as well as the first study of a single delivery system that combines two components uniquely engineered for complementary interactions with mucus.

Perioperative levosimendan in cardiac surgery: A systematic review with meta-analysis and trial sequential analysis

BACKGROUND

Several studies suggested beneficial effects of perioperative levosimendan on postoperative outcome after cardiac surgery. However, three large randomized controlled trials (RCTs) have been recently published and presented neutral results. We performed a systematic review with meta-analysis and trial sequential analysis (TSA) to assess benefits and harms of perioperative levosimendan therapy in cardiac surgery.

METHODS

Electronic databases were searched up to September 2017 for RCTs on preoperative levosimendan versus any type of control. The Cochrane methodology was employed. We calculated odds ratio (OR) or Risk Ratio (OR) and 95% confidence interval (CI) using fixed-effects meta-analyses and we further performed TSA.

RESULTS

We included data from 40 RCTs and 4246 patients. Pooled analysis of 5 low risk of bias trials (1910 patients) showed no association between levosimendan and mortality (OR 0.86 [95% CI, 0.62, 1.18], p=0.34, TSA inconclusive), acute kidney injury, need of renal replacement therapy, myocardial infarction, ventricular arrhythmias, and serious adverse events, but an association with higher incidence of supraventricular arrhythmias (RR 1.11 [95% CI, 1.00, 1.24], p=0.05, TSA inconclusive) and hypotension (RR 1.15 [95% CI, 1.01, 1.30], p=0.04, TSA inconclusive). Analysis including all 40 trials found that levosimendan was associated with lower postoperative mortality (OR 0.56 [95% CI, 0.44, 0.71], p<0.00001, TSA conclusive), acute kidney injury, and renal replacement therapy, and higher incidence of hypotension.

CONCLUSIONS

There is not enough high-quality evidence to neither support nor discourage the systematic use of levosimendan in cardiac surgery.

Implementing the EffTox dose-finding design in the Matchpoint trial

BACKGROUND

The Matchpoint trial aims to identify the optimal dose of ponatinib to give with conventional chemotherapy consisting of fludarabine, cytarabine and idarubicin to chronic myeloid leukaemia patients in blastic transformation phase. The dose should be both tolerable and efficacious. This paper describes our experience implementing EffTox in the Matchpoint trial.

METHODS

EffTox is a Bayesian adaptive dose-finding trial design that jointly scrutinises binary efficacy and toxicity outcomes. We describe a nomenclature for succinctly describing outcomes in phase I/II dose-finding trials. We use dose-transition pathways, where doses are calculated for each feasible set of outcomes in future cohorts. We introduce the phenomenon of dose ambivalence, where EffTox can recommend different doses after observing the same outcomes. We also describe our experiences with outcome ambiguity, where the categorical evaluation of some primary outcomes is temporarily delayed.

RESULTS

We arrived at an EffTox parameterisation that is simulated to perform well over a range of scenarios. In scenarios where dose ambivalence manifested, we were guided by the dose-transition pathways. This technique facilitates planning, and also helped us overcome short-term outcome ambiguity.

CONCLUSIONS

EffTox is an efficient and powerful design, but not without its challenges. Joint phase I/II clinical trial designs will likely become increasingly important in coming years as we further investigate non-cytotoxic treatments and streamline the drug approval process. We hope this account of the problems we faced and the solutions we used will help others implement this dose-finding clinical trial design.

TRIAL REGISTRATION

Matchpoint was added to the European Clinical Trials Database ( https://www.clinicaltrialsregister.eu/ctr-search/trial/2012-005629-65/GB ) on 2013-12-30.

Restoring auditory cortex plasticity in adult mice by restricting thalamic adenosine signaling

Circuits in the auditory cortex are highly susceptible to acoustic influences during an early postnatal critical period. The auditory cortex selectively expands neural representations of enriched acoustic stimuli, a process important for human language acquisition. Adults lack this plasticity. Here we show in the murine auditory cortex that juvenile plasticity can be reestablished in adulthood if acoustic stimuli are paired with disruption of ecto-5'-nucleotidase-dependent adenosine production or A1-adenosine receptor signaling in the auditory thalamus. This plasticity occurs at the level of cortical maps and individual neurons in the auditory cortex of awake adult mice and is associated with long-term improvement of tone-discrimination abilities. We conclude that, in adult mice, disrupting adenosine signaling in the thalamus rejuvenates plasticity in the auditory cortex and improves auditory perception.

Ambrisentan: a review of its use in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a progressive disease defined by an elevation in pulmonary arterial pressure that can lead to right heart failure and death. Ambrisentan is a selective endothelin receptor antagonist approved for the treatment of idiopathic, heritable PAH and connective tissue disease-associated PAH. Ambrisentan has been shown to improve exercise capacity and hemodynamics with an acceptable side-effect profile. It has also proven to be safely used in combination with other PAH-specific medications, especially with phosphodiesterase-5 inhibitors. In the recent randomized trial, AMBITION, it was shown that upfront combination therapy of ambrisentan and tadalafil significantly decreased the risk of clinical failure compared with monotherapy. This review describes the drug profile of ambrisentan and its safety and efficacy in the treatment of PAH.

Levosimendan for Hemodynamic Support after Cardiac Surgery

BACKGROUND

Acute left ventricular dysfunction is a major complication of cardiac surgery and is associated with increased mortality. Meta-analyses of small trials suggest that levosimendan may result in a higher rate of survival among patients undergoing cardiac surgery.

METHODS

We conducted a multicenter, randomized, double-blind, placebo-controlled trial involving patients in whom perioperative hemodynamic support was indicated after cardiac surgery, according to prespecified criteria. Patients were randomly assigned to receive levosimendan (in a continuous infusion at a dose of 0.025 to 0.2 μg per kilogram of body weight per minute) or placebo, for up to 48 hours or until discharge from the intensive care unit (ICU), in addition to standard care. The primary outcome was 30-day mortality.

RESULTS

The trial was stopped for futility after 506 patients were enrolled. A total of 248 patients were assigned to receive levosimendan and 258 to receive placebo. There was no significant difference in 30-day mortality between the levosimendan group and the placebo group (32 patients [12.9%] and 33 patients [12.8%], respectively; absolute risk difference, 0.1 percentage points; 95% confidence interval [CI], -5.7 to 5.9; P=0.97). There were no significant differences between the levosimendan group and the placebo group in the durations of mechanical ventilation (median, 19 hours and 21 hours, respectively; median difference, -2 hours; 95% CI, -5 to 1; P=0.48), ICU stay (median, 72 hours and 84 hours, respectively; median difference, -12 hours; 95% CI, -21 to 2; P=0.09), and hospital stay (median, 14 days and 14 days, respectively; median difference, 0 days; 95% CI, -1 to 2; P=0.39). There was no significant difference between the levosimendan group and the placebo group in rates of hypotension or cardiac arrhythmias.

CONCLUSIONS

In patients who required perioperative hemodynamic support after cardiac surgery, low-dose levosimendan in addition to standard care did not result in lower 30-day mortality than placebo. (Funded by the Italian Ministry of Health; CHEETAH ClinicalTrials.gov number, NCT00994825 .).

Chromatographic Study of Azintamide in Bulk Powder and in Pharmaceutical Formulation in the Presence of Its Degradation Form

Two specific, sensitive, and precise stability-indicating chromatographic methods were developed, optimized, and validated for the determination of Azintamide (AZ) in the presence of its degradation product. The first method was TLC combined with the densitometric determination of the separated bands. Separation was achieved using silica gel 60 F254 TLC plates and chloroform-acetone-glacial acetic acid (7.5 + 2.1 + 0.4, v/v/v) as the developing system. Good correlations were obtained between the integrated peak area of the studied drug and its corresponding concentrations in the linearity range. The second method used HPLC with UV diode-array detection, in which the proposed method was applied for the quantitative determination of AZ in the presence of its acidic degradation product and the quantitative determination of the acid-induced degradation product of AZ (AZ Deg) using pentoxifylline as the internal standard. The proposed components were separated on a reversed-phase C18 analytical column using acetonitrile-water (50 + 50, v/v). The flow rate was maintained at 0.55 mL/min and the detection wavelength was 260 nm. Linear regressions were obtained in the range of 1-30 and 0.3-16 μg/mL for AZ and AZ Deg, respectively. Different parameters affecting the suggested methods were optimized for maximum separation of the cited components. The suggested methods were validated in compliance with the International Conference on Harmonization guidelines and successfully applied for the determination of AZ in its pure powder form and in its pharmaceutical formulation. Both methods were also statistically compared with the reported method with no significant difference in performance observed.

Challenges in the development of an M4 PAM in vivo tool compound: The discovery of VU0467154 and unexpected DMPK profiles of close analogs

This letter describes the chemical optimization of a novel series of M4 positive allosteric modulators (PAMs) based on a 5-amino-thieno[2,3-c]pyridazine core, developed via iterative parallel synthesis, and culminating in the highly utilized rodent in vivo tool compound, VU0467154 (5). This is the first report of the optimization campaign (SAR and DMPK profiling) that led to the discovery of VU0467154, and details all of the challenges faced in allosteric modulator programs (steep SAR, species differences in PAM pharmacology and subtle structural changes affecting CNS penetration).

Chronic Unpredictable Mild Stress Induces Loss of GABA Inhibition in Corticotrophin-Releasing Hormone-Expressing Neurons through NKCC1 Upregulation

INTRODUCTION

Prolonged and repeated stresses cause hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. The corticotrophin-releasing hormone (CRH)-expressing neurons in the hypothalamic paraventricular nucleus (PVN) are an essential component of the HPA axis.

MATERIALS AND METHODS

Chronic unpredictable mild stress (CUMS) was induced in Sprague-Dawley rats. GABA reversal potentials (EGABA) were determined by using gramicidin-perforated recordings in identified PVN-CRH neurons through expressing enhanced green fluorescent protein driven by the CRH promoter. Plasma corticosterone (CORT) levels were measured in rats implanted with a cannula targeting the lateral ventricles and PVN.

RESULTS

Blocking the GABAA receptor in the PVN with gabazine significantly increased plasma CORT levels in unstressed rats but did not change CORT levels in CUMS rats. CUMS caused a depolarizing shift in EGABA in PVN-CRH neurons compared with EGABA in PVN-CRH neurons in unstressed rats. Furthermore, CUMS induced a long-lasting increase in expression levels of the cation chloride cotransporter Na+-K+-Cl--Cl- (NKCC1) in the PVN but a transient decrease in expression levels of K+-Cl--Cl- in the PVN, which returned to the basal level 5 days after CUMS treatment. The NKCC1 inhibitor bumetanide decreased the basal firing activity of PVN-CRH neurons and normalized EGABA and the gabazine-induced excitatory effect on PVN-CRH neurons in CUMS rats. In addition, central administration of bumetanide decreased basal circulating CORT levels in CUMS rats.

CONCLUSIONS

These data suggest that chronic stress impairs GABAergic inhibition, resulting in HPA axis hyperactivity through upregulation of NKCC1.

Levosimendan, a new therapeutic approach to prevent delayed cerebral vasospasm after subarachnoid hemorrhage?

BACKGROUND

Under physiological cerebral conditions, levosimendan, a calcium-channel sensitizer, has a dose-dependent antagonistic effect on prostaglandin F2alpha (PGF)-induced vasoconstriction. This circumstance could be used in antagonizing delayed cerebral vasospasm (dCVS), one of the main complications after subarachnoid hemorrhage (SAH), leading to delayed cerebral ischemia and ischemic neurological deficits. Data already exist that identified neuroprotective effects of levosimendan in a traumatic brain injury model and additionally, it has been proven that this compound prevents narrowing of the basilar artery (BA) luminal area after SAH in an in vitro rabbit model. Takotsubo cardiomyopathy, a severe ventricular dysfunction, is also a well-known complication after SAH, associated with pulmonary edema and prolonged intubation.

METHODS

The polypeptide endothelin-1 (ET-1) plays a key role in the development of dCVS after SAH. Therefore, the aim of the present investigation was to detect functional interactions between the calcium-sensitizing and the ET-1-dependent vasoconstriction after experimental-induced SAH; interactions between levosimendan and a substrate-specific vasorelaxation in the BA were also examined. It was reviewed whether levosimendan has a beneficial influence on endothelin(A) and/or endothelin(B₁) receptors (ET-(A) and ET-(B₁) receptors) in cerebral vessels after SAH. We also examined whether this drug could have antagonistic effects on a PGF-induced vasoconstriction.

RESULTS

Under treatment with levosimendan after SAH, the endothelin system seems to be affected. The ET-1-induced contraction is decreased, not significantly. In addition, we detected changes in the nitric oxide-cyclic guanosine monophosphate (NO-cGMP) pathway. Preincubation with levosimendan causes a modulatory effect on the ET-(B₁) receptor-dependent vasorelaxation. It induces an upregulation of the NO-cGMP pathway with a significantly increased relaxation. Even after PGF-induced precontraction a dose-dependent relaxation was registered, which was significantly higher (E_max) and earlier (pD₂) compared to the concentration-effect curve without levosimendan.

CONCLUSIONS

After experimental-induced dCVS, levosimendan seems to restore the well-known impaired function of the vasorelaxant ET-(B₁) receptor. Levosimendan also reversed the PGF-induced contraction dose-dependently. Both of these mechanisms could be used for antagonizing dCVS in patients suffering SAH. Levosimendan could even be used additionally in treating patients developing takotsubo cardiomyopathy.

Deficient adolescent social behavior following early-life inflammation is ameliorated by augmentation of anandamide signaling

Early-life inflammation has been shown to exert profound effects on brain development and behavior, including altered emotional behavior, stress responsivity and neurochemical/neuropeptide receptor expression and function. The current study extends this research by examining the impact of inflammation, triggered with the bacterial compound lipopolysaccharide (LPS) on postnatal day (P) 14, on social behavior during adolescence. We investigated the role that the endocannabinoid (eCB) system plays in sociability after early-life LPS. To test this, multiple cohorts of Sprague Dawley rats were injected with LPS on P14. In adolescence, rats were subjected to behavioral testing in a reciprocal social interaction paradigm as well as the open field. We quantified eCB levels in the amygdala of P14 and adolescent animals (anandamide and 2-arachidonoylglycerol) as well as adolescent amygdaloid cannabinoid receptor 1 (CB1) binding site density and the hydrolytic activity of the enzyme fatty acid amide hydrolase (FAAH), which metabolizes the eCB anandamide. Additionally, we examined the impact of FAAH inhibition on alterations in social behavior. Our results indicate that P14 LPS decreases adolescent social behavior (play and social non-play) in males and females at P40. This behavioral alteration is accompanied by decreased CB1 binding, increased anandamide levels and increased FAAH activity. Oral administration of the FAAH inhibitor PF-04457845 (1mg/kg) prior to the social interaction task normalizes LPS-induced alterations in social behavior, while not affecting social behavior in the control group. Infusion of 10ng PF-04457845 into the basolateral amygdala normalized social behavior in LPS injected females. These data suggest that alterations in eCB signaling following postnatal inflammation contribute to impairments in social behavior during adolescence and that inhibition of FAAH could be a novel target for disorders involving social deficits such as social anxiety disorders or autism.

PREVENTION OF HEART FAILURE PATIENTS WITH DECREASED EJECTION FRACTION IN NON-CARDIAC SURGERY: LEVOSIMENDAN OR ANESTHETIC CARDIOPROTECTION?

BACKGROUND

Chronic heart failure (CHF) significantly worsens the prognosis of surgical treatment in noncardiac surgery, doubling mortality in compared with patients with coronary artery disease. Modern anesthesiology has at least two methods that potentially can improve the results in noncardiac surgery: anesthetic cardioprotection and the prevention of CHF decompensation with levosimendan.

THE AIM

to study the efficacy of anesthetic cardioprotection andpreoperative preparation with levosimendan for the prevention of CHF decompensation in patients with reduced left ventricular ejectionfraction in noncardiac surgery.

ENDPOINTS

the primary endpoint of the trial is the need and the maximum dose of inotropic drugs in the perioperative period; secondary point: the length of stay in the ICU, composite outcome, the dynamics of SI, FI, the content ofNT-proBNP and TnT Materials and methods: A randomized study was performed in three groups of patients during reconstructive operations on infrarenal part of aorta: control (traditional methodfor prevention of decompensation of CHF were used) - 31 patients; the group with the anesthetic cardioprotectivei - 31 patients; the group with a preoperative preparing with levosimendan - 30 patients.

RESULTS

The incidence of heart failure (estimated by need to use inotropic drugs - IS) was 83% of control group patients and 75% of the patients of the group "VIMA" (p = 0,65). The number ofpatients needing the use of dobutamine in LS-group was significantly below, 50% (p = 0,02 relative to control group and p = 0,08 compared to the group VIMA). IS in the control group was 8 [6, 9] μg xkg⁻¹ - xmin⁻¹ ; group VIMA 8 [3; 9] mg xkg ⁻¹ xmin⁻¹ , whereas in the LS group only 2 [0; 7] mg ⁻¹ xkg⁻¹ xmin⁻¹ . Differences between groups credible, given the Bonferroni correction (p = 0,0015). In our study, was not identified significant differences in 30-day mortality: in the control group it was 3,4%; in the group VIMA of 3,1%; in the group of LS - 0% (p > 0,017); however, a composite outcome (number of adverse events (heart attack+stroke+mortality) were slightly better in the LS group - 17%, against 34% in the control group (p = 0,043).

CONCLUSION

Preoperative preparation with levosimendan in patients with reduced fraction left ventricle ejection when performing reconstructive operations on the descending aorta reduces the incidence of episodes of decompensation of heart failure compared with the control group to 39,8% (p < 0,05). The use of this technique improves the composite outcome of operations on the infrarenal aorta. The study has not shown the influence of anesthetic cardioprotection in terms of hospitalization and composite outcome of surgical treatment.

Interaction between Darunavir and Etravirine Is Partly Mediated by CYP3A5 Polymorphism

OBJECTIVES

To assess the impact of the loss-of-function CYP3A5*3 allele (rs776746, 6986A>G SNP) on darunavir (DRV) plasma concentrations.

METHODS

135 HIV-1 infected patients treated with DRV-based therapy were included in the study and plasma samples were obtained immediately before drug intake in order to determine DRV trough concentrations using an ultra performance liquid chromatography method (UPLC) with diode-array detection (DAD). Noteworthy is the fact that in 16 (11.9%) patients, etravirine (ETR) was combined with DRV. CYP3A5 genotypes were determined using real time PCR method (TaqMan® genotyping assay). The patients were then classified into CYP3A5 expressors (CYP3A5*1 allele carriers) and non-expressors (CYP3A5*3 homozygous). Subsequently, the association between DRV plasma trough concentration ([DRV]plasma) and CYP3A5 genotype-based expression status was analyzed.

RESULTS

45% of the patients were classified as CYP3A5 expressors. In the whole cohort, mean [DRV]plasma was not different between CYP3A5 expressors and non-expressors (1894ng/ml [CI95%: 1566-2290] versus 1737ng/ml [CI95%: 1468-2057], p = 0.43). However, in the subgroup of the 16 patients receiving DRV combined with ETR, a significantly lower [DRV]plasma was observed for CYP3A5 expressors when compared to non-expressors (1385ng/ml [CI95%:886.3-2165] versus 3141ng/ml [CI95%:2042-4831], p = 0.007).

CONCLUSIONS

Interaction between DRV and ETR is partly mediated by CYP3A5 polymorphism with lower DRV plasma trough concentrations in CYP3A5 expressors suggesting a specific ETR-driven CYP3A5 activation only in CYP3A5 expressors. Consequently, these patients might be more at risk of infra-therapeutic [DRV]plasma. This potentially important observation is a good illustration of a genotype-based drug interaction, which could also have considerable consequences if translated to other CYP3A5-metabolized drugs. Further investigations are thus needed to confirm this association and to explore its clinical impact, mainly in the African population among whom CYP3A5 expressors are more frequent, before recommending systematic CYP3A5 pre-emptive genotyping for DRV-ETR co-administration.

[A COMPARISON OF TWO APPROACHES FOR INTRAOPERATIVE LEVOSIMENDAN ADMINISTRATION IN CARDIAC SURGICAL PATIENTS WITH SEVERE LEFT VENTRICLE DYSFUNCTION.]

BACKGROUND

It is proved that levosimendan administration improves overall outcome and reduces mortality in high risk cardiac patients. However up to now there is no optimal scheme of its use in intraoperative settings.

THE AIM

To compare two approaches of levosimendan administration in patients with left ventricle ejectionfraction less than 35% who underwent cardiac surgery.

MATERIALS AND METHODS

After approval by the local ethics Committee, 40 patients older than 18 years with severe preoperative left ventricular dysfunction (left ventricle ejection fraction less than 35%), who were planned for cardiac surgery operation with cardiopulmonary bypass and cardioplegia were randomly assigned to two groups of 20 patients each. In group I (n=20) infusion of levosimendan started intraoperatively after induction of anesthesia, a loading dose of 6 mg/kg with subsequent injection of a dose of 0.1 μg/kg/minfor 24 hours. In group 2 (n=20) bolus of levosimendan 24 μg/kg was injected 15 min before aortic clamping. Anesthesia and methods of cardiopulmonary bypass in the groups did not differ Results. We got thefavorable clinical results in a group of 'full" levosimendan dose (12.5 mg as a daily infusion with an, initial bolus of 6 mg/kg just after the induction of anesthesia) in terms ofreduction of the total dose ofsympathomimetics andpostoperative troponin T level in comparison with the group where levosimendan was administered as a single bolus. (24 mg/kg) 15 minutes prior to aortic clamping.

CONCLUSION

Based on these data it can be assumed that the use of prolonged infusion of levosimendan in a dosage of 12.5 mg is preferable to a single bolus 24 μg/kg.

Combination therapy with copanlisib and ABL tyrosine kinase inhibitors against Philadelphia chromosome-positive resistant cells

ABL tyrosine kinase inhibitor (TKI) therapy has improved the survival of patients with Philadelphia (Ph) chromosome-positive leukemia. However, ABL TKIs cannot eradicate leukemia stem cells. Therefore, new therapeutic approaches for Ph-positive leukemia are needed. Aberrant activation of phosphoinositide 3-kinase (PI3K) signaling is important for the initiation and maintenance of human cancers. Copanlisib (BAY80-6946) is a potent inhibitor of PI3Kα and PI3K-δ. Here we investigated the efficacy of combination therapy of copanlisib with an ABL TKI (imatinib, nilotinib, or ponatinib) using BCR-ABL-positive cells. Although the effects of the ABL TKI treatment were reduced in the presence of the feeder cell line, HS-5, copanlisib inhibited cell growth. Upon combining ABL TKI and copanlisib, cell growth was reduced. Ponatinib and copanlisib combined therapy reduced tumor volume and increased survival in mouse allograft models, respectively. These results indicate that the PI3Kα and -δ inhibitors overcame the chemoprotective effects of the feeder cells and enhanced ABL TKI cytotoxicity. Thus, co-treatment with ABL TKI and copanlisib may be a powerful strategy against ABL TKI-resistant cells, including those harboring the related T315I mutation.

Cardiomyopathy in a Harris hawk (Parabuteo unicinctus)

CASE DESCRIPTION An adult sexually intact female Harris hawk (Parabuteo unicinctus) housed at a wildlife hospital was evaluated because of acute collapse during an educational exhibition. CLINICAL FINDINGS Physical examination and hematologic analysis revealed no abnormalities; radiography revealed findings consistent with a previous tibiotarsal fracture. Coelioscopy with histologic examination and fungal culture of lung and air sac samples revealed anthracosis but no fungal infection. The hawk was discharged and temporarily removed from the education program; 1 month later, upon reintroduction into the program, it collapsed again. Physical examination and hematologic findings were similar to those after the first episode. Transcoelomic and transesophageal echocardiography and CT angiocardiography findings were consistent with cardiomyopathy. TREATMENT AND OUTCOME Initial cardiac treatment included furosemide (0.5 mg/kg [0.23 mg/lb], PO, q 24 h) and pimobendan (10 mg/kg [4.5 mg/lb], PO, q 12 h). After 10 days of treatment, peak and trough plasma concentrations of pimobendan were measured at 25, 196 and 715.97 ng/mL, respectively; the dosage was decreased to 0.25 mg/kg (0.11 mg/lb), PO, every 12 hours. No overt signs of toxicosis were detected. A sample was collected to reevaluate plasma pimobendan concentration after 30 days of treatment; results were not obtained prior to the patient's death but revealed a peak concentration of 16.8 ng/mL, with an undetectable trough concentration. The hawk was found dead 6 months after initial evaluation. Necropsy revealed cardiomegaly, but histologic examination did not reveal an inciting cause of cardiac dysfunction. CLINICAL RELEVANCE Cardiac disease in raptors may be underreported. Transcoelomic and transesophageal echocardiography and CT angiography provided useful information for the diagnosis of cardiac disease in the hawk of this report.

Effectiveness of prophylactic levosimendan in patients with impaired left ventricular function undergoing coronary artery bypass grafting: a randomized pilot study

OBJECTIVES

Perioperative low cardiac output syndrome occurs in 3-14% of patients undergoing isolated coronary artery bypass grafting (CABG), leading to significant increase in major morbidity and mortality. Considering the unique pharmacological and pharmacokinetic properties of levosimendan, we conducted a prospective, double-blind, randomized pilot study to evaluate the effectiveness of prophylactic levosimendan in patients with impaired left ventricular function undergoing CABG.

METHODS

Thirty-two patients undergoing CABG with low left ventricular ejection fraction (LVEF ≤ 40%) were randomized to receive either a continuous infusion of levosimendan at a dose of 0.1 μg/kg/min for 24 h without a loading dose or a placebo. The primary outcome of the study was the change in the LVEF assessed with transthoracic echocardiography on the seventh postoperative day. Secondary outcomes included the physiological and clinical effects of levosimendan.

RESULTS

All patients tolerated preoperative infusion of levosimendan well. The LVEF improved in both groups; this increase was statistically significant in the levosimendan group (from 35.8 ± 5% preoperatively to 42.8 ± 7.8%, P = 0.001) compared with the control group (from 37.5 ± 3.4% preoperatively to 41.2 ± 8.3%, P = 0.1). The cardiac index, SvO₂, pulmonary capillary wedge pressure and right ventricular stroke work index showed a similar trend, which was optimized in patients treated with levosimendan. Moreover, an increase in extravascular lung water was noticed in this group during the first 24 h after surgery.

CONCLUSIONS

This pilot study shows that prophylactic levosimendan infusion is safe and effective in increasing the LVEF postoperatively in patients with impaired cardiac function undergoing coronary surgery. This finding may be translated to 'optimizing' patients' status before surgery.

Cost-benefits of incorporating levosimendan into cardiac surgery practice: German base case

OBJECTIVE

To evaluate the cost-benefit of using levosimendan compared with dobutamine, in the perioperative treatment of patients undergoing cardiac surgery who require inotropic support.

METHODS

A two-part Markov model was designed to simulate health-state transitions of patients undergoing cardiac surgery, and estimate the short- and long-term health benefits of treatment. Hospital length of stay (LOS), mortality, medication, and adverse events were key clinical- and cost-inputs. Cost-benefits were evaluated in terms of costs and bed stays within the German healthcare system. Drug prices were calculated from the German Drug Directory (€/2014) and published literature, with a 3% annual discount rate applied. The base case analysis was for a 1-year time horizon.

RESULTS

The use of levosimendan vs dobutamine was associated with cost savings of €4787 per patient from the German hospital perspective due to reduced adverse events and shorter hospital LOS, leading to increased bed capacity and hospital revenue.

LIMITATIONS

A pharmacoeconomic calculation for the specific situation of the German healthcare system that is based on international clinical trial carries a substantial risk of disregarding potentially relevant but unknown confounding factors (i.e., ICU-staffing, co-medications, standard-ICU care vs fast-tracking, etc.) that may either attenuate or increase the outcome pharmacoeconomic effects of a drug; however, since these conditions would also apply for patients treated with comparators, their net effects may not necessarily influence the conclusions.

CONCLUSIONS

The use of levosimendan in patients undergoing cardiac surgery who require inotropic support appears to be cost-saving. The results of the analysis provide a strong rationale to run local clinical studies with pharmacoeconomic end-points which would allow a much more precise computation of the benefits of levosimendan.

A phase 1 study of the safety, tolerability, pharmacokinetics, and pharmacodynamics of TAK-063, a selective PDE10A inhibitor

RATIONALE

Schizophrenia is a complex neuropsychiatric disorder characterized, in part, by impaired dopamine signaling. TAK-063 is a selective inhibitor of phosphodiesterase 10A, a key regulator of intracellular signaling pathways that is highly expressed in the striatum.

OBJECTIVE

Safety, tolerability, and pharmacokinetics of TAK-063 were evaluated in a phase 1 study.

METHODS

Healthy Japanese and non-Japanese volunteers were randomized into dose cohorts of 3, 10, 30, 100, 300, and 1000 mg. Each fasting volunteer randomly received a single dose of TAK-063 or placebo. Individuals from the 100-mg cohort also received a post-washout, 100-mg dose under fed conditions. A total of 84 volunteers enrolled (14 per cohort).

RESULTS

The most common drug-related adverse events (AEs) were somnolence (33.3 %), orthostatic tachycardia (19.7 %), and orthostatic hypotension (9.1 %). The three severe AEs recorded occurred at the highest doses: orthostatic hypotension (n = 1; 300 mg) and somnolence (n = 2; 1000 mg). There were no deaths, serious AEs, or discontinuations due to AEs. TAK-063 exposure increased in a dose-dependent manner. Median T _max was reached 3 to 4 h postdose. Fed conditions slowed absorption (T _max = 6 h) and increased oral bioavailability. Renal elimination was negligible. Safety and pharmacokinetic parameters were similar between Japanese and non-Japanese subjects. Impairments in cognitive function consistent with the effects of other sedative or hypnotic agents were detected using a validated, computerized cognition battery, CNS Vital Signs.

CONCLUSIONS

TAK-063 was safe and well tolerated at doses up to 1000 mg and demonstrated a pharmacokinetic profile supporting once-daily dosing. Further evaluation of the clinical safety and efficacy of TAK-063 is warranted.