Predicting survival in patients with 'non-high-risk' acute variceal bleeding receiving ß-blockers+ligation to prevent re-bleeding.

BACKGROUND & AIMS: Pre-emptive transjugular intrahepatic portosystemic shunt (TIPS) is the treatment of choice for high-risk acute variceal bleeding (AVB; i.e., Child-Turcotte-Pugh [CTP] B8-9+active bleeding/C10-13). Nevertheless, some 'non-high-risk' patients have poor outcomes despite the combination of non-selective beta-blockers and endoscopic variceal ligation for secondary prophylaxis. We investigated prognostic factors for re-bleeding and mortality in 'non-high-risk' AVB to identify subgroups who may benefit from more potent treatments (i.e., TIPS) to prevent further decompensation and mortality. METHODS: A total of 2,225 adults with cirrhosis and variceal bleeding were prospectively recruited at 34 centres between 2011-2015; for the purpose of this study, case definitions and information on prognostic indicators at index AVB and on day 5 were further refined in low-risk patients, of whom 581 (without failure to control bleeding or contraindications to TIPS) who were managed by non-selective beta-blockers/endoscopic variceal ligation, were finally included. Patients were followed for 1 year. RESULTS: Overall, 90 patients (15%) re-bled and 70 (12%) patients died during follow-up. Using clinical routine data, no meaningful predictors of re-bleeding were identified. However, re-bleeding (included as a time-dependent co-variable) increased mortality, even after accounting for differences in patient characteristics (adjusted cause-specific hazard ratio: 2.57; 95% CI 1.43-4.62; p = 0.002). A nomogram including CTP, creatinine, and sodium measured at baseline accurately (concordance: 0.752) stratified the risk of death. CONCLUSION: The majority of 'non-high-risk' patients with AVB have an excellent prognosis, if treated according to current recommendations. However, about one-fifth of patients, i.e. those with CTP ≥8 and/or high creatinine levels or hyponatremia, have a considerable risk of death within 1 year of the index bleed. Future clinical trials should investigate whether elective TIPS placement reduces mortality in these patients. IMPACT AND IMPLICATIONS: Pre-emptive transjugular intrahepatic portosystemic shunt placement improves outcomes in high-risk acute variceal bleeding; nevertheless, some 'non-high-risk' patients have poor outcomes despite the combination of non-selective beta-blockers and endoscopic variceal ligation. This is the first large-scale study investigating prognostic factors for re-bleeding and mortality in 'non-high-risk' acute variceal bleeding. While no clinically meaningful predictors were identified for re-bleeding, we developed a nomogram integrating baseline Child-Turcotte-Pugh score, creatinine, and sodium to stratify mortality risk. Our study paves the way for future clinical trials evaluating whether elective transjugular intrahepatic portosystemic shunt placement improves outcomes in presumably 'non-high-risk' patients who are identified as being at increased risk of death.

Hepatic encephalopathy is not a contraindication to pre-emptive TIPS in high-risk patients with cirrhosis with variceal bleeding.

BACKGROUND: A pre-emptive transjugular intrahepatic portosystemic shunt (pTIPS) reduces mortality in high-risk patients with cirrhosis (Child-Pugh C/B+active bleeding) with acute variceal bleeding (AVB). Real-life studies point out that <15% of patients eligible for pTIPS ultimately undergo transjugular intrahepatic portosystemic shunt (TIPS) due to concerns about hepatic encephalopathy (HE). The outcome of patients undergoing pTIPS with HE is unknown. We aimed to (1) assess the prevalence of HE in patients with AVB; (2) evaluate the outcome of patients presenting HE at admission after pTIPS; and (3) determine if HE at admission is a risk factor for death and post-TIPS HE. PATIENTS AND METHODS: This is an observational study including 2138 patients from 34 centres between October 2011 and May 2015. Placement of pTIPS was based on individual centre policy. Patients were followed up to 1 year, death or liver transplantation. RESULTS: 671 of 2138 patients were considered at high risk, 66 received pTIPS and 605 endoscopic+drug treatment. At admission, HE was significantly more frequent in high-risk than in low-risk patients (39.2% vs 10.6%, p<0.001). In high-risk patients with HE at admission, pTIPS was associated with a lower 1-year mortality than endoscopic+drug (HR 0.374, 95% CI 0.166 to 0.845, p=0.0181). The incidence of HE was not different between patients treated with pTIPS and endoscopic+drug (38.2% vs 38.7%, p=0.9721), even in patients with HE at admission (56.4% vs 58.7%, p=0.4594). Age >56, shock, Model for End-Stage Liver Disease score >15, endoscopic+drug treatment and HE at admission were independent factors of death in high-risk patients. CONCLUSION: pTIPS is associated with better survival than endoscopic treatment in high-risk patients with cirrhosis with variceal bleeding displaying HE at admission.

Alcohol-related liver disease phenotype impacts survival after an acute variceal bleeding episode.

BACKGROUND & AIMS: Alcohol-related hepatitis (AH) encompasses a high mortality. AH might be a concomitant event in patients with acute variceal bleeding (AVB). The current study aimed to assess the prevalence of AH in patients with AVB and to compare the clinical outcomes of AH patients to other alcohol-related liver disease (ALD) phenotypes and viral cirrhosis. METHODS: Multicentre, observational study including 916 patients with AVB falling under the next categories: AH (n = 99), ALD cirrhosis actively drinking (d-ALD) (n = 285), ALD cirrhosis abstinent from alcohol (a-ALD) (n = 227) and viral cirrhosis (n = 305). We used a Cox proportional hazards model to calculate adjusted hazard ratio (HR) of death adjusted by MELD. RESULTS: The prevalence of AH was 16% considering only ALD patients. AH patients exhibited more complications. Forty-two days transplant-free survival was worse among AH, but statistical differences were only observed between AH and d-ALD groups (84 vs. 93%; p = 0.005), when adjusted by MELD no differences were observed between AH and the other groups. At one-year, survival of AH patients (72.7%) was similar to the other groups; when adjusted by MELD mortality HR was better in AH compared to a-ALD (0.48; 0.29-0.8, p = 0.004). Finally, active drinkers who remained abstinent presented better survival, independently of having AH. CONCLUSIONS: Contrary to expected, AH patients with AVB present no worse one-year survival than other patients with different alcohol-related phenotypes or viral cirrhosis. Abstinence influences long-term survival and could explain these counterintuitive results.

Bacterial infections in patients with acute variceal bleeding in the era of antibiotic prophylaxis.

BACKGROUND & AIMS: Antibiotic prophylaxis reduces the risk of infection and mortality in patients with cirrhosis and acute variceal bleeding (AVB). This study examines the incidence of, and risk factors for, bacterial infections during hospitalization in patients with AVB on antibiotic prophylaxis. METHODS: A post hoc analysis was performed using the database of an international, multicenter, observational study designed to examine the role of pre-emptive transjugular intrahepatic portosystemic shunts in patients with cirrhosis and AVB. Data were collected on patients with cirrhosis hospitalized for AVB (n = 2,138) from a prospective cohort (October 2013-May 2015) at 34 referral centers, and a retrospective cohort (October 2011-September 2013) at 19 of these centers. The primary outcome was incidence of bacterial infection during hospitalization. RESULTS: A total of 1,656 patients out of 1,770 (93.6%) received antibiotic prophylaxis; third-generation cephalosporins (76.2%) and quinolones (19.0%) were used most frequently. Of the patients on antibiotic prophylaxis, 320 patients developed bacterial infection during hospitalization. Respiratory infection accounted for 43.6% of infections and for 49.7% of infected patients, and occurred early after admission (median 3 days, IQR 1-6). On multivariate analysis, respiratory infection was independently associated with Child-Pugh C (odds ratio [OR] 3.1; 95% CI 1.4-6.7), grade III-IV encephalopathy (OR 2.8; 95% CI 1.8-4.4), orotracheal intubation for endoscopy (OR 2.6; 95% CI 1.8-3.8), nasogastric tube placement (OR 1.7; 95% CI 1.2-2.4) or esophageal balloon tamponade (OR 2.4; 95% CI 1.2-4.9). CONCLUSION: Bacterial infections develop in almost one-fifth of patients with AVB despite antibiotic prophylaxis. Respiratory infection is the most frequent, is an early event after admission, and is associated with advanced liver failure, severe hepatic encephalopathy and use of nasogastric tube, orotracheal intubation for endoscopy or esophageal balloon tamponade. LAY SUMMARY: Bacterial infections develop during hospitalization in close to 20% of patients with acute variceal bleeding despite antibiotic prophylaxis. Respiratory bacterial infections are the most frequent and occur early after admission. Respiratory infection is associated with advanced liver disease, severe hepatic encephalopathy and a need for a nasogastric tube, orotracheal intubation for endoscopy or esophageal balloon tamponade.

Rebleeding and mortality risk are increased by ACLF but reduced by pre-emptive TIPS.

BACKGROUND & AIMS: The relationship between acute-on-chronic liver failure (ACLF) and acute variceal bleeding (AVB) is poorly understood. Specifically, the prevalence and prognosis of ACLF in the context of AVB is unclear, while the role of transjugular intrahepatic portosystemic shunt (TIPS) in the management in patients with ACLF has not been described to date. METHODS: A multicenter, international, observational study was conducted in 2,138 patients from 34 centers between 2011 and 2015. ACLF was defined and graded according to the EASL-CLIF consortium definition. Placement of pre-emptive TIPS (pTIPS) was based on individual center policy. Patients were followed-up for 1 year, until death or liver transplantation. Cox regression and competing risk models (Gray's test) were used to identify independent predictors of rebleeding or mortality. RESULTS: At admission, 380/2,138 (17.8%) patients had ACLF according to EASL-CLIF criteria (grade 1: 38.7%; grade 2: 39.2%; grade 3: 22.1%). The 42-day rebleeding (19% vs. 10%; p <0.001) and mortality (47% vs. 10%; p <0.001) rates were higher in patients with ACLF and increased with ACLF grades. Of note, the presence of ACLF was independently associated with rebleeding and mortality. pTIPS placement improved survival in patients with ACLF at 42 days and 1 year. This effect was also observed in propensity score matching analysis of 66 patients with ACLF, of whom 44 received pTIPs and 22 did not. CONCLUSIONS: This large multicenter international real-life study identified ACLF at admission as an independent predictor of rebleeding and mortality in patients with AVB. Moreover, pTIPS was associated with improved survival in patients with ACLF and AVB. LAY SUMMARY: Acute variceal bleeding is a deadly complication of liver cirrhosis that results from severe portal hypertension. This study demonstrates that the presence of acute-on-chronic liver failure (ACLF) is the strongest predictor of mortality in patients with acute variceal bleeding. Importantly, patients with ACLF and acute variceal (re)bleeding benefit from pre-emptive (early) placement of a transjugular intrahepatic portosystemic shunt.

Preemptive-TIPS Improves Outcome in High-Risk Variceal Bleeding: An Observational Study.

Patients admitted with acute variceal bleeding (AVB) and Child-Pugh C score (CP-C) or Child-Pugh B plus active bleeding at endoscopy (CP-B+AB) are at high risk for treatment failure, rebleeding, and mortality. A preemptive transjugular intrahepatic portosystemic shunt (p-TIPS) has been shown to improve survival in these patients, but its use in clinical practice has been challenged and not routinely incorporated. The present study aimed to further validate the role of preemptive TIPS in a large number of high-risk patients. This multicenter, international, observational study included 671 patients from 34 centers admitted for AVB and high risk of treatment failure. Patients were managed according to current guidelines, and use of drugs and endoscopic therapy (D+E) or p-TIPS was based on individual center policy. p-TIPS in the setting of AVB is associated with a lower mortality in CP-C patients compared with D+E (1 year mortality 22% vs. 47% in D+E group; P = 0.002). Mortality rate in CP-B+AB patients was low, and p-TIPS did not improve it. In CP-C and CP-B+AB patients, p-TIPS reduced treatment failure and rebleeding (1-year cumulative incidence function probability of remaining free of the composite endpoint: 92% vs. 74% in the D+E group; P = 0.017) and development of de novo or worsening of previous ascites without increasing rates of hepatic encephalopathy. Conclusion: p-TIPS must be the treatment of choice in CP-C patients with AVB. Because of the strong benefit in preventing further bleeding and ascites, p-TIPS could be a good treatment strategy for CP-B+AB patients.

Survival of patients with cirrhosis and acute peptic ulcer bleeding compared with variceal bleeding using current first-line therapies.

The presence of cirrhosis increases the mortality of patients with peptic ulcer bleeding (PUB). Both acute variceal bleeding (AVB) and PUB are associated with substantial mortality in cirrhosis. This multicenter cohort study was performed to assess whether the mortality of patients with cirrhosis with PUB is different from that of those with AVB. Patients with cirrhosis and acute gastrointestinal bleeding were consecutively included and treated with somatostatin and proton pump inhibitor infusion from admission and with antibiotic prophylaxis. Emergency endoscopy with endoscopic therapy was performed within the first 6 hours. 646 patients with AVB and 144 with PUB were included. There were baseline differences between groups, such as use of gastroerosive drugs or ß-blockers. Child-Pugh and Model for End-Stage Liver Disease MELD scores were similar. Further bleeding was more frequent in the AVB group than those in the PUB group (18% vs. 10%; odds ratio [OR] = 0.50; 95% confidence interval [CI] = 0.29-0.88). However, mortality risk at 45 days was similar in both groups (19% in the AVB group vs. 17% in the PUB group; OR = 0.85; 95% CI = 0.55-1.33; P = 0.48). Different parameters, such as Child-Pugh score, acute kidney injury, acute on chronic liver failure, or presence of shock or bacterial infection, but not the cause of bleeding, were related to the risk of death. Only 2% of the PUB group versus 3% of the AVB group died with uncontrolled bleeding (P = 0.39), whereas the majority of patients in either group died from liver failure or attributed to other comorbidities. CONCLUSION: Using current first-line therapy, patients with cirrhosis and acute peptic ulcer bleeding have a similar survival than those with variceal bleeding. The risk of further bleeding is higher in patients with variceal hemorrhage. However, few patients in both groups died from uncontrolled bleeding, rather the cause of death was usually related to liver failure or comorbidities. (Hepatology 2018;67:1458-1471).

Apixaban-induced liver injury.

The use of new oral anticoagulants such as apixaban is increasing. We present the case of an 85-year-old patient who was diagnosed with mixed profile toxic hepatitis due to apixaban use. An etiological study was negative, except for anti-smooth muscle antibodies, and a liver biopsy ruled out autoimmune hepatitis. The patient was assigned a score of 7 on the CIOMS/RUCAM scale, indicating a probable causality. The liver injury improved after the withdrawal of apixaban. A previous meta-analysis reported that the risk of hepatotoxicity does not increase with the use of apixaban, nor were any cases reported in registry studies. Nonetheless, more than 120 possible cases currently appear in the European pharmacovigilance database (EudraVigilance). We suggest that apixaban should be considered as a possible cause of liver injury.

Utility of histology for the diagnosis of portal hypertensive gastroenteropathy. Concordance between the endoscopic image and gastrointestinal biopsies. Role of the CD34 marker. / Utilidad de la histología para el diagnóstico de la gastroenteropatía por hipertensión portal. Concordancia entre la imagen endoscópica y las biopsias gastrointestinales. Papel del marcador CD34.

INTRODUCTION: Upper gastroscopy in patients with cirrhosis often reveals non-specific lesions, which are usually oriented as portal hypertensive gastropathy (PHG). However, the diagnosis of PHG can be difficult, both from an endoscopic and histological point of view. The study of CD34 expression, which enhances the endothelial cells of the microvasculature, could help the differential diagnosis. The objectives of this study were to evaluate the correlation between endoscopy and histology in the diagnosis of PHG and to assess the utility of CD34 in the diagnosis of PHG. MATERIAL AND METHODS: The results of immunostaining with CD34 gastric fundus biopsies from 100 cirrhotic patients and 20 controls were compared with the endoscopic images. RESULTS: The correlation between the histology and the endoscopic diagnosis of PHG was very low (kappa=0.15). In addition, the measurement of the diameter of the gastric vessels enhanced by the use of immunohistochemical staining (CD34) did not show good correlation with the endoscopic diagnosis (p=.26) and did not provide relevant information for the histological diagnosis of PHG either. DISCUSSION: The correlation between histology and endoscopy is low for the diagnosis of PHG. The use of immunostaining for CD34 does not seem to improve the diagnostic yield of the histological study.

Inter and intra-observer concordance for the diagnosis of portal hypertension gastropathy.

INTRODUCTION: At present there is no fully accepted endoscopic classification for the assessment of the severity of portal hypertensive gastropathy (PHG). Few studies have evaluated inter and intra-observer concordance or the degree of concordance between different endoscopic classifications. OBJECTIVES: To evaluate inter and intra-observer agreement for the presence of portal hypertensive gastropathy and enteropathy using different endoscopic classifications. METHODS: Patients with liver cirrhosis were included into the study. Enteroscopy was performed under sedation. The location of lesions and their severity was recorded. Images were videotaped and subsequently evaluated independently by three different endoscopists, one of whom was the initial endoscopist. The agreement between observations was assessed using the kappa index. RESULTS: Seventy-four patients (mean age 63.2 years, 53 males and 21 females) were included. The agreement between the three endoscopists regarding the presence or absence of PHG using the Tanoue and McCormack classifications was very low (kappa scores = 0.16 and 0.27, respectively). CONCLUSIONS: The current classifications of portal hypertensive gastropathy have a very low degree of intra and inter-observer agreement for the diagnosis and assessment of gastropathy severity.

Prognostic factors of liver cirrhosis mortality after a first episode of spontaneous bacterial peritonitis. A multicenter study.

INTRODUCTION: Spontaneous bacterial peritonitis is an infectious complication with a negative impact on survival of patients with cirrhosis. OBJECTIVE: To analyze the short- and long-term survival after a first episode of bacterial peritonitis and the associated prognostic factors. PATIENTS AND METHODS: This was a retrospective, multicenter study of patients admitted to hospital for spontaneous bacterial peritonitis between 2008 and 2013. Independent variables related to mortality were analyzed by logistic regression. The prognostic power of the Child Pugh Score, the Model for End-Stage Liver Disease (MELD) and the Charlson index was analyzed by ROC curve. RESULTS: A total of 159 patients were enrolled, 72% were males with a mean age of 63.5 years and a mean MELD score of 19 (SD ± 9.5). Mortality at 30 and 90 days and one and two years was 21%, 31%, 55% and 69%, respectively. Hepatic encephalopathy (p = 0.008, OR 3.5, 95% CI 1.4-8.8) and kidney function (p = 0.026, OR 2.7, 95% CI 1.13-16.7) were independent factors for short- and long-term mortality. MELD was a good marker of short- and long-term survival (area under the curve [AUC] 0.7: 95% CI 1.02-1.4). The Charlson index was related to long-term mortality (AUC 0.68: 95% CI 0.6-0.77). CONCLUSIONS: Short- and long-term mortality of spontaneous bacterial peritonitis is still high. The main prognostic factors for mortality are impairment of liver and kidney function. MELD and the Charlson index are good markers of survival.

Engineering Highly Potent and Selective Microproteins against Nav1.7 Sodium Channel for Treatment of Pain.

The prominent role of voltage-gated sodium channel 1.7 (Nav1.7) in nociception was revealed by remarkable human clinical and genetic evidence. Development of potent and subtype-selective inhibitors of this ion channel is crucial for obtaining therapeutically useful analgesic compounds. Microproteins isolated from animal venoms have been identified as promising therapeutic leads for ion channels, because they naturally evolved to be potent ion channel blockers. Here, we report the engineering of highly potent and selective inhibitors of the Nav1.7 channel based on tarantula ceratotoxin-1 (CcoTx1). We utilized a combination of directed evolution, saturation mutagenesis, chemical modification, and rational drug design to obtain higher potency and selectivity to the Nav1.7 channel. The resulting microproteins are highly potent (IC50 to Nav1.7 of 2.5 nm) and selective. We achieved 80- and 20-fold selectivity over the closely related Nav1.2 and Nav1.6 channels, respectively, and the IC50 on skeletal (Nav1.4) and cardiac (Nav1.5) sodium channels is above 3000 nm The lead molecules have the potential for future clinical development as novel therapeutics in the treatment of pain.

Impact of anticoagulation on upper-gastrointestinal bleeding in cirrhosis. A retrospective multicenter study.

UNLABELLED: Recent studies have shown that liver cirrhosis (LC) behaves as an acquired hypercoagulable state with increased thrombotic risk. This is why anticoagulation therapy (AT) is now frequently used in these patients. Variceal bleeding is a severe complication of LC. It is unknown whether AT may impact the outcome of bleeding in these patients. Fifty-two patients on AT with upper gastrointestinal bleeding (UGIB) were evaluated. Portal vein thrombosis (PVT) and different cardiovascular disorders (CVDs) were the indication for AT in 14 and 38 patients, respectively. Overall, 104 patients with LC and UGIB not under AT matched for severity of LC, age, sex, source of bleeding, and Sequential Organ Failure Assessment (SOFA) score served as controls. UGIB was attributed to portal hypertension (PH) in 99 (63%) patients and peptic/vascular lesions in 57 (37%). Twenty-six (17%) patients experienced 5-day failure; SOFA, source of UGIB, and PVT, but not AT, were independent predictors of 5-day failure. In addition, independent predictors of 6-week mortality, which was observed in 26 (11%) patients, were SOFA, Charlson Comorbidity index, and use of AT for a CVD. There were no differences between patients with/without AT in needs for rescue therapies, intensive care unit admission, transfusions, and hospital stay. CONCLUSIONS: Factors that impact the outcome of UGIB in patients under AT are degree of multiorgan failure and comorbidity, but not AT itself.

Effects of a multidisciplinary approach on the effectiveness of antiviral treatment for chronic hepatitis C.

UNLABELLED:  Background. Despite the introduction of direct antiviral agents, pegylated interferon remains the mainstay of treatment for chronic hepatitis C. However, pegylated interferon is associated with a high rate of severe adverse events and decreased quality of life. Specific interventions can improve adherence and effectiveness. We aimed to determine whether implementing a multidisciplinary approach improved outcomes in the treatment of chronic hepatitis C. MATERIAL AND METHODS: We analyzed consecutive patients treated with pegylated interferon plus ribavirin between August 2001 and December 2011. We compared patients treated before and after the implementation of a multidisciplinary approach in 2007. We compared the baseline demographic and clinical characteristics and laboratory findings between groups, and used bivariate logistic regression models to detect factors involved in attaining a sustained virological response, calculating the odds ratios with their respective 95% confidence intervals. To evaluate the effect of the multidisciplinary team, we fitted a multivariate logistic regression model to compare the sustained virological response after adjusting for unbalanced variables and predictive factors. RESULTS: We included 514 patients [228 (44.4%) in the pre-intervention cohort]. Age, viral genotype, previous treatment, aspartate transaminase, ferritin, and triglyceride were prognostic factors of sustained virological response. After adjusting for prognostic factors, sustained virological response was higher in the multidisciplinary cohort (58 vs. 48%, p = 0.038). Despite higher psychiatric comorbidity and age in the multidisciplinary cohort, we observed a trend toward a lower rate of treatment abandonment in this group (2.2 vs. 4.9%, p = 0.107). CONCLUSION: Multidisciplinary management of chronic hepatitis C improves outcomes.

Effect of attachment site on stability of cleavable antibody drug conjugates.

The systemic stability of the antibody-drug linker is crucial for delivery of an intact antibody-drug conjugate (ADC) to target-expressing tumors. Linkers stable in circulation but readily processed in the target cell are necessary for both safety and potency of the delivered conjugate. Here, we report a range of stabilities for an auristatin-based payload site-specifically attached through a cleavable valine-citrulline-p-aminobenzylcarbamate (VC-PABC) linker across various sites on an antibody. We demonstrate that the conjugation site plays an important role in determining VC-PABC linker stability in mouse plasma, and that the stability of the linker positively correlates with ADC cytotoxic potency both in vitro and in vivo. Furthermore, we show that the VC-PABC cleavage in mouse plasma is not mediated by Cathepsin B, the protease thought to be primarily responsible for linker processing in the lysosomal degradation pathway. Although the VC-PABC cleavage is not detected in primate plasma in vitro, linker stabilization in the mouse is an essential prerequisite for designing successful efficacy and safety studies in rodents during preclinical stages of ADC programs. The divergence of linker metabolism in mouse plasma and its intracellular cleavage offers an opportunity for linker optimization in the circulation without compromising its efficient payload release in the target cell.

Recurrent drug-induced liver injury (DILI) with ciprofloxacin and amoxicillin/clavulanic.

Ciprofloxacin and amoxicillin/clavulanic are two widely used antibiotics due to their high efficacy and few side effects. While the percentage of hepatotoxicity of these antibiotics is low, their frequent use has led to a progressive increase in the number of cases. Both antibiotics have been associated with a wide variety of hepatotoxic reactions, from a slight rise of transaminases to fulminant hepatitis. Once hepatotoxicity secondary to a drug appears, the first step is to discontinue the drug. Physicians may opt to administer an alternative treatment with a different chemical structure. It should be borne in mind, however, that different chemical structures may also cause recurrent drug-induced liver injuries (DILI). We present the case of a patient who consecutively developed DILI due to ciprofloxacin and amoxicillin/clavulanic.

[Gastric vascular lesions in cirrhosis: gastropathy and antral vascular ectasia]. / Lesiones vasculares gástricas en la cirrosis: gastropatía y ectasia vascular antral.

Portal hypertensive gastropathy (GHP) is a complication of portal hypertension usually associated with liver cirrhosis. The pathogenesis is unclear but the presence of portal hypertension is an essential factor for its development. GHP may be asymptomatic or present as gastrointestinal bleeding or iron deficiency anemia. Endoscopic lesions vary from a mosaic pattern to diffuse red spots; the most common location is the fundus. Treatment is indicated when there is acute or chronic bleeding, as secondary prophylaxis. There is insufficient evidence to recommend primary prophylaxis in patients who have never bled. Drugs that decrease portal pressure, such as non-cardioselective beta-blockers, and/or endoscopic ablative treatments, such as argon-beam coagulation, may be used. The role of transarterial intrahepatic portosystemic shunt) or bypass surgery has been insufficiently analyzed. Antral vascular ectasia (EVA) is a rare entity in liver cirrhosis, whose pathophysiology is still unknown. Clinical presentation is similar to that of GHP and endoscopy usually shows red spots in the antrum. Biopsy is often required to differentiate EVA from GHP. There is no effective medical therapy, so endoscopic ablative therapy and, in severe cases, antrectomy are recommended.

Mass spectrometric characterization of transglutaminase based site-specific antibody-drug conjugates.

Antibody drug conjugates (ADCs) are becoming an important new class of therapeutic agents for the treatment of cancer. ADCs are produced through the linkage of a cytotoxic small molecule (drug) to monoclonal antibodies that target tumor cells. Traditionally, most ADCs rely on chemical conjugation methods that yield heterogeneous mixtures of varying number of drugs attached at different positions. The potential benefits of site-specific drug conjugation in terms of stability, manufacturing, and improved therapeutic index has recently led to the development of several new site-specific conjugation technologies. However, detailed characterization of the degree of site specificity is currently lacking. In this study we utilize mass spectrometry to characterize the extent of site-specificity of an enzyme-based site-specific antibody-drug conjugation technology that we recently developed. We found that, in addition to conjugation of the engineered site, a small amount of aglycosylated antibody present in starting material led to conjugation at position Q295, resulting in approximately 1.3% of off-target conjugation. Based on our detection limits, we show that Q295N mutant eliminates the off-target conjugation yielding highly homogeneous conjugates that are better than 99.8% site-specific. Our study demonstrates the importance of detailed characterization of ADCs and describes methods that can be utilized to characterize not only our enzyme based conjugates, but also ADCs generated by other conjugation technologies.

Increasing serum half-life and extending cholesterol lowering in vivo by engineering antibody with pH-sensitive binding to PCSK9.

Target-mediated clearance and high antigen load can hamper the efficacy and dosage of many antibodies. We show for the first time that the mouse, cynomolgus, and human cross-reactive, antagonistic anti-proprotein convertase substilisin kexin type 9 (PCSK9) antibodies J10 and the affinity-matured and humanized J16 exhibit target-mediated clearance, resulting in dose-dependent pharmacokinetic profiles. These antibodies prevent the degradation of low density lipoprotein receptor, thus lowering serum levels of LDL-cholesterol and potently reducing serum cholesterol in mice, and selectively reduce LDL-cholesterol in cynomolgus monkeys. In order to increase the pharmacokinetic and efficacy of this promising therapeutic for hypercholesterolemia, we engineered pH-sensitive binding to mouse, cynomolgus, and human PCSK9 into J16, resulting in J17. This antibody shows prolonged half-life and increased duration of cholesterol lowering in two species in vivo by binding to endogenous PCSK9 in mice and cynomolgus monkeys, respectively. The proposed mechanism of this pH-sensitive antibody is that it binds with high affinity to PCSK9 in the plasma at pH 7.4, whereas the antibody-antigen complex dissociates at the endosomal pH of 5.5-6.0 in order to escape from target-mediated degradation. Additionally, this enables the antibody to bind to another PCSK9 and therefore increase the antigen-binding cycles. Furthermore, we show that this effect is dependent on the neonatal Fc receptor, which rescues the dissociated antibody in the endosome from degradation. Engineered pH-sensitive antibodies may enable less frequent or lower dosing of antibodies hampered by target-mediated clearance and high antigen load.