Primary Sclerosing Cholangitis-Associated Pouchitis: A Distinct Clinical Phenotype.

BACKGROUND & AIMS: Patients with primary sclerosing cholangitis (PSC) commonly undergo ileal pouch-anal anastomosis (IPAA) for medically-refractory ulcerative colitis (UC) or colorectal dysplasia. Pouchitis develops more frequently in patients with PSC, potentially leading to increased morbidity. We aimed to assess clinical characteristics and treatment outcomes for pouchitis in patients with PSC compared to a matched, non-PSC cohort. METHODS: All patients with PSC who underwent IPAA and were diagnosed with pouchitis (PSC-pouchitis) were identified. A matched cohort composed of non-PSC patients who underwent IPAA for UC and subsequently developed pouchitis (UC-pouchitis) was developed. Relevant demographic, clinical, endoscopic, histologic, and treatment data were collected and compared between groups. RESULTS: Of those with PSC-pouchitis (n=182), 53.9% and 46.1% underwent IPAA for medically-refractory disease and dysplasia, respectively, compared to 88.7% and 11.3% in the UC-pouchitis group (P < .001). Patients with PSC-pouchitis were more likely to develop chronic pouchitis (68.1% vs 34.1%; P < .001), have moderate-to-severe pouch inflammation (54.9% vs 32.4%; P < .001), and prepouch ileitis (34.1% vs 11.5%; P < .001) compared to UC-pouchitis. Of those with PSC-pouchitis, 50.6% and 17.6% developed chronic antibiotic-dependent or antibiotic-refractory pouchitis, respectively, compared to 25.8% and 7.7% with UC-pouchitis. There was no difference in treatment response between the two groups with use of thiopurines, anti-tumor necrosis factor agents, and newer biologics. CONCLUSIONS: PSC-associated pouchitis presents with a unique clinical phenotype, characterized by increased risk of chronic pouchitis, moderate-to-severe pouch inflammation, prepouch ileitis, and less response to conventional antimicrobial therapy.

De Novo Colitis Associated With Rituximab in 21 Patients at a Tertiary Center.

Rituximab, a monoclonal antibody directed against the CD20 antigen on B lymphocytes, is commonly used in the treatment of hematologic malignancies and rheumatologic disorders.1,2 It acts to rapidly deplete the B lymphocyte population through multiple mechanisms, leading to dysregulation of the immune system.3 Rituximab has been associated with numerous adverse gastrointestinal effects including diarrhea and bowel perforation, and recent reports have associated rituximab with the development of de novo inflammatory bowel disease (IBD).4,5 To our knowledge, there have been no reports of microscopic colitis (MC) associated with rituximab therapy. We aimed to identify patients with rituximab-associated colitis, and to better characterize the clinical features and disease course of these patients.

An Update on the Medical Management of Inflammatory Pouch Complications.

Total proctocolectomy with ileal pouch-anal anastomosis is the surgical procedure of choice for patients with medically-refractory ulcerative colitis or ulcerative colitis with associated dysplasia. Although most patients after ileal pouch-anal anastomosis experience good functional outcomes, a number of complications may develop. Of the long-term complications, pouchitis is most common. Although most respond to antibiotic treatment, some patients develop chronic pouchitis, leading to substantial morbidity and occasionally pouch failure. In patients with pouchitis who are not responsive to conventional antimicrobial therapy, secondary causes of chronic pouchitis need to be considered, including Crohn's disease of the pouch. In recent years, more literature has become available regarding the medical management of chronic pouchitis and Crohn's disease of the pouch, including the use of newer biologic agents. We herein provide a concise review on inflammatory complications involving the ileal pouch, including a focused approach to diagnosis and medical management.

Nonrelaxing Pelvic Floor Dysfunction Is an Underestimated Complication of Ileal Pouch-Anal Anastomosis.

BACKGROUND & AIMS: Nonrelaxing pelvic floor dysfunction (N-RPFD), or dyssynergic defecation, is the paradoxical contraction and/or impaired relaxation of pelvic floor and anal muscles during defecation. Few studies have evaluated this disorder in patients with an ileal pouch-anal anastomosis (IPAA). We investigated the frequency of N-RPFD in patients with and without chronic pouchitis following IPAA and the effectiveness of biofeedback therapy within this population. METHODS: We conducted a retrospective study of all patients with an IPAA who underwent anorectal manometry between January 2000 and March 2015 (n = 111). N-RPFD was diagnosed in patients with symptoms consistent with a pouch evacuation disorder and 1 or more of the following abnormal tests: anorectal manometry, balloon expulsion test, barium or magnetic resonance defecography, or external anal sphincter electromyography. Patients who completed biofeedback therapy were identified and assessed to determine symptomatic response. RESULTS: Of the 111 patients evaluated, 83 (74.8%) met criteria for N-RPFD. A significantly higher proportion of patients with chronic pouchitis were diagnosed with N-RPFD than patients without chronic pouchitis (83.3% vs 62.2%, respectively; P = .012). Most patients diagnosed with N-RPFD had abnormal results from the balloon expulsion test (78.3%); 53.0% of patients diagnosed with N-RPFD had abnormal findings from external anal sphincter electromyography, 25.3% had abnormal defecography findings, and 20.5% had abnormal findings from anorectal manometry. Twenty-two patients completed biofeedback therapy: 15 patients (68.2%) had mild-moderate improvement and 5 patients (22.7%) had significant improvement of symptoms. CONCLUSIONS: N-RPFD occurs in almost 75% of patients with an IPAA, especially in patients with chronic pouchitis. Biofeedback seems to be an effective therapy for patients with an IPAA and N-RPFD, but further studies are needed for validation.

Dual Inhibition of Bruton's Tyrosine Kinase and Phosphoinositide-3-Kinase p110δ as a Therapeutic Approach to Treat Non-Hodgkin's B Cell Malignancies.

Although new targeted therapies, such as ibrutinib and idelalisib, have made a large impact on non-Hodgkin's lymphoma (NHL) patients, the disease is often fatal because patients are initially resistant to these targeted therapies, or because they eventually develop resistance. New drugs and treatments are necessary for these patients. One attractive approach is to inhibit multiple parallel pathways that drive the growth of these hematologic tumors, possibly prolonging the duration of the response and reducing resistance. Early clinical trials have tested this approach by dosing two drugs in combination in NHL patients. We discovered a single molecule, MDVN1003 (1-(5-amino-2,3-dihydro-1H-inden-2-yl)-3-(8-fluoro-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-yl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine), that inhibits Bruton's tyrosine kinase and phosphatidylinositol-3-kinase δ, two proteins regulated by the B cell receptor that drive the growth of many NHLs. In this report, we show that this dual inhibitor prevents the activation of B cells and inhibits the phosphorylation of protein kinase B and extracellular signal-regulated kinase 1/2, two downstream mediators that are important for this process. Additionally, MDVN1003 induces cell death in a B cell lymphoma cell line but not in an irrelevant erythroblast cell line. Importantly, we found that this orally bioavailable dual inhibitor reduced tumor growth in a B cell lymphoma xenograft model more effectively than either ibrutinib or idelalisib. Taken together, these results suggest that dual inhibition of these two key pathways by a single molecule could be a viable approach for treatment of NHL patients.

Discovery of pyrazolopyrimidine derivatives as novel inhibitors of ataxia telangiectasia and rad3 related protein (ATR).

The ATR pathway is a critical mediator of the replication stress response in cells. In aberrantly proliferating cancer cells, this pathway can help maintain sufficient genomic integrity for cancer cell progression. Herein we describe the discovery of 19, a pyrazolopyrimidine-containing inhibitor of ATR via a strategic repurposing of compounds targeting PI3K.

Clinical implications of serial versus isolated biliary fluorescence in situ hybridization (FISH) polysomy in primary sclerosing cholangitis.

BACKGROUND: Cholangiocarcinoma (CCA) is a leading cause of death in patients with primary sclerosing cholangitis (PSC). Biliary polysomy detected by fluorescence in situ hybridization (FISH) helps to identify patients with early CCA, but not all PSC patients with polysomy develop CCA. Here, we examined the features and clinical outcomes of PSC patients with serial versus isolated polysomy. METHODS: All patients with PSC who underwent ≥1 endoscopic retrograde cholangiography (ERC) with FISH testing at Mayo Clinic, Rochester from 2008-2011 were identified. Patients diagnosed with CCA at the time of initial polysomy were excluded. Serial polysomy was defined as polysomy on ≥2 ERCs; isolated polysomy was defined as polysomy once followed by all nonpolysomy results. The primary outcome was the diagnosis of CCA. RESULTS: Twenty-seven patients with polysomy and ≥1 subsequent ERC with FISH were identified. Of these, 11 (40.7%) had serial polysomy and 16 (59.3%) had isolated polysomy. CCA was more likely to be diagnosed in patients with serial versus isolated polysomy (36.4% vs. 6.3%; p = .046). Overall, four patients (36.4%) with serial polysomy and three (18.8%) with isolated polysomy underwent liver transplantation (LT), with time to LT being significantly shorter for the former (14.0 vs. 65.4 months; p = .0003). CONCLUSIONS: Biliary polysomy reverted in ≥50% of patients with PSC; this group appears to be at decreased risk of CCA compared to those with serial polysomy. Nevertheless, both groups should be followed closely, and those with serial polysomy may benefit from early LT evaluation.

Pouchitis Is a Common Complication in Patients With Familial Adenomatous Polyposis Following Ileal Pouch-Anal Anastomosis.

BACKGROUND & AIMS: Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the surgical procedure most commonly selected for patients with familial adenomatous polyposis (FAP) or ulcerative colitis that is refractive to medical treatment. Pouchitis is the most common complication in patients with ulcerative colitis after IPAA, but is thought to rarely occur in patients with FAP. We investigated the frequency of pouchitis and other pouch-related complications in patients with FAP after IPAA. METHODS: We performed a retrospective cohort study of all patients with FAP who underwent IPAA at a single tertiary institution from 1992 through 2015 (n = 113). Patients were identified using International Classification of Diseases-9 diagnostic and current procedural terminology codes. We obtained relevant demographic and clinical data from patients' electronic medical records. The frequencies of pouchitis and pouch-related complications were determined. RESULTS: Twenty-five patients (22.1%) developed pouchitis (mean time to pouchitis, 4.1 years) and 88 did not (77.9%). Patients with pouchitis showed a trend toward developing late (>90 days after IPAA) pouch-related complications (56.0% of patients with pouchitis developed late complications, compared with 36.4% without). In patients who developed pouchitis, the disease course was acute in 72.0% and chronic in 28.0%. Of those treated, 69.6% responded to antibiotics, 13.0% became dependent on antibiotics, and 13.0% developed antibiotic resistance. CONCLUSIONS: Pouchitis is more prevalent in patients with FAP than previously believed. Although pouchitis seems to occur later in patients with FAP than in patients with ulcerative colitis, and have a milder course, it should be considered a common complication among patients with FAP following IPAA.

Targeting prostate cancer with compounds possessing dual activity as androgen receptor antagonists and HDAC6 inhibitors.

While enzalutamide and abiraterone are approved for treatment of metastatic castration-resistant prostate cancer (mCRPC), approximately 20-40% of patients have no response to these agents. It has been stipulated that the lack of response and the development of secondary resistance to these drugs may be due to the presence of AR splice variants. HDAC6 has a role in regulating the androgen receptor (AR) by modulating heat shock protein 90 (Hsp90) acetylation, which controls the nuclear localization and activation of the AR in androgen-dependent and independent scenarios. With dual-acting AR-HDAC6 inhibitors it should be possible to target patients who don't respond to enzalutamide. Herein, we describe the design, synthesis and biological evaluation of dual-acting compounds which target AR and are also specific towards HDAC6. Our efforts led to compound 10 which was found to have potent dual activity (HDAC6 IC50=0.0356µM and AR binding IC50=<0.03µM). Compound 10 was further evaluated for antagonist and other cell-based activities, in vitro stability and pharmacokinetics.

Bioactivation of sitaxentan in liver microsomes, hepatocytes, and expressed human P450s with characterization of the glutathione conjugate by liquid chromatography tandem mass spectrometry.

Sitaxentan is a selective endothelin-A receptor antagonist that was marketed as Thelin in several European countries and Canada for pulmonary arterial hypertension. Sitaxentan was undergoing further clinical trials in the United States but due to four deaths and one case of liver transplantation from severe liver toxicity that appeared to be idiosyncratic in nature, it was withdrawn worldwide in December, 2010. Sitaxentan contains a 1,3-benzodioxole ring that undergoes enzymatic demethyleneation to an ortho-catechol metabolite that can further oxidize to a reactive ortho-quinone metabolite. Here, we report the detection and mass spectral characterization of a glutathione conjugate of this sitaxentan quinone reactive metabolite that was trapped in vitro using mouse, rat, dog, and human liver microsomes supplemented with NADPH and glutathione and that was also observed in rat and human hepatocytes. Using human liver microsomes, we also demonstrated that P450 3A4 undergoes time-dependent inhibition. Density functional calculations on the catechol metabolite of sitaxentan indicated that the reaction leading to the quinone was thermodynamically favorable with an enthalpy change of -6.3 kcal/mol. Using density functional methodology, we modeled the attack of glutathione on the quinone with an S-methyl thiolate anion which allowed us to predict, based on the difference in transition state energies, that the 2-position on the phenyl ring was more likely than the 5-position as the site of glutathione conjugation. Overall, our results demonstrated that sitaxentan is capable of facile formation of a reactive ortho-quinone metabolite capable of reacting with glutathione and may rationalize the idiosyncratic nature of the hepatotoxicity that led to its withdrawal.

Triazolopyridazine LRRK2 kinase inhibitors.

Leucine-rich repeat kinase 2 (LRRK2) has been implicated in the pathogenesis of Parkinson's disease (PD). Inhibition of LRRK2 kinase activity is a therapeutic approach that may lead to new treatments for PD. Herein we report the discovery of a series of [1,2,4]triazolo[4,3-b]pyridazines that are potent against both wild-type and mutant LRRK2 kinase activity in biochemical assays and show an unprecedented selectivity towards the G2019S mutant. A structural rational for the observed selectivity is proposed.

Discovery of 4-alkylamino-7-aryl-3-cyanoquinoline LRRK2 kinase inhibitors.

Mutations in leucine-rich repeat kinase 2 (LRRK2) are associated with familial Parkinson's disease (PD). The kinase activity of this complex protein is increased by pathogenic mutations. Inhibition of LRRK2 kinase activity has therefore emerged as a promising approach for the treatment of PD. Herein we report our findings on a series of 4-alkylamino-7-aryl-3-cyanoquinolines that exhibit kinase inhibitory activity against both wild type and G2019S mutant LRRK2. Activity was determined in both biochemical and cellular assays. Compound 14 was further evaluated in an in vivo pharmacodynamic study and found to significantly inhibit Ser935 phosphorylation after oral dosing.

Novel cinnoline-based inhibitors of LRRK2 kinase activity.

Leucine rich repeat kinase 2 (LRRK2) has been implicated in the pathogenesis of Parkinson's disease (PD). Inhibition of LRRK2 kinase activity is a therapeutic approach that may lead to new treatments for PD. Herein we report the discovery of a series of cinnoline-3-carboxamides that are potent against both wild-type and mutant LRRK2 kinase activity in biochemical assays. These compounds are also shown to be potent inhibitors in a cellular assay and to have good to excellent CNS penetration.

Discovery of a novel [3.2.1] benzo fused bicyclic sulfonamide-pyrazoles as potent, selective and efficacious γ-secretase inhibitors.

Structure-activity relationship (SAR) of a novel, potent and metabolically stable series of benzo [3.2.1] bicyclic sulfonamide-pyrazoles as γ-secretase inhibitors are described. Compounds that are efficacious in reducing the cortical Aßx-40 levels in FVB mice via oral dose, as well as those with high selectivity over Notch, are highlighted.

Design and synthesis of hydroxyethylamine (HEA) BACE-1 inhibitors: prime side chromane-containing inhibitors.

The structure activity relationship of the prime region of conformationally restricted hydroxyethylamine (HEA) BACE inhibitors is described. Variation of the P1' region provided selectivity over Cat-D with a series of 2,2-dioxo-isothiochromanes and optimization of the P2' substituent of chromane-HEA(s) with polar substituents provided improvements in the compound's in vitro permeability. Significant potency gains were observed with small aliphatic substituents such as methyl, n-propyl, and cyclopropyl when placed at the C-2 position of the chromane.

Altered Bile Acid and Pouch Microbiota Composition in Patients With Chronic Pouchitis.

BACKGROUND: Patients with ulcerative colitis and total abdominal proctocolectomy with ileal pouch-anal anastomosis have a 50% risk of pouchitis and a 5% to 10% risk of chronic pouchitis. AIMS: The goal of the study was to compare pouch microbiota and stool bile acid composition in patients with chronic pouchitis, chronic pouchitis and primary sclerosing cholangitis, and normal pouch. METHODS: Patients with ulcerative colitis and ileal pouch-anal anastomosis were recruited from March 20, 2014, to August 6, 2019, and categorized into normal pouch, chronic pouchitis, and chronic pouchitis/primary sclerosing cholangitis groups. Stool samples were subjected to bile acid quantification and 16S rRNA gene sequencing. Statistical comparisons of absolute bile acid abundance and pouch microbiota α-diversity, ß-diversity, and taxa abundance were performed among the patient groups. RESULTS: A total of 51 samples were analyzed. Both α-diversity (P = .01, species richness) and ß-diversity (P = .001) significantly differed among groups. Lithocholic acid was significantly lower in patients with chronic pouchitis/primary sclerosing cholangitis than in those with chronic pouchitis (P = .01) or normal pouch (P = .03). Decreased α-diversity was associated with an increased primary to secondary bile acid ratio (P = .002), which was also associated with changes in ß-diversity (P = .006). CONCLUSIONS: Pouch microbiota α- and ß-diversity differed among patients with normal pouch, chronic pouchitis, and chronic pouchitis/primary sclerosing cholangitis. Lithocholic acid level and primary to secondary bile acid ratio were highly associated with pouch microbiota richness, structure, and composition. These findings emphasize the associations between pouch microbiota and bile acid composition in dysbiosis and altered metabolism, suggesting that secondary bile acids are decreased in chronic pouchitis.

The α- and ß-diversity of the pouch microbiota significantly differed in chronic pouchitis, chronic pouchitis and primary sclerosing cholangitis, and normal pouch. Microbiota changes were associated with stool bile acid composition. Decreased diversity was associated with decreased secondary bile acids.

Defining normal pouch function in patients with ileal pouch-anal anastomosis: a pilot study.

BACKGROUND: Most patients experience good functional outcomes following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis. AIM: We aimed to determine if asymptomatic patients with an IPAA had findings consistent with normal defecation on standard objective anorectal tests. METHODS: Patients 18-65 years old with IPAA and self-reported healthy pouch function were recruited. Patients with chronic pouchitis, Crohn's disease, anastomotic stricture, or indication for IPAA other than ulcerative or indeterminate colitis were excluded. Patients underwent an interview with an abbreviated Rome Questionnaire followed by high-resolution ano-pouch manometry, balloon expulsion test, pouch barostat, and magnetic resonance (MR) defecography. RESULTS: Twenty patients completed all testing. Six patients were excluded from the final analysis due to symptoms suggestive of pouch evacuation disorder on the abbreviated Rome Questionnaire (n = 2), structural abnormality on MR imaging (n = 3), or both (n = 1). Of the remaining 14 patients, mean anal resting pressure during high-resolution manometry was 72 ± 16 mmHg, mean anal squeeze pressure was 247 ± 69 mmHg, and mean pouch-anal gradient during the simulated evacuation was -27 ± 37 mmHg. The meantime to balloon expulsion was 54 seconds. During dynamic MR defecography, the mean descent of ano-pouch junction was 2.6 cm, and mean pouch evacuation was 44.5% and 74.2% pre- and posttoilet phase, respectively. CONCLUSIONS: A substantial proportion of patients with IPAA and self-reported healthy pouch function have anatomic and/or functional abnormalities of the pouch. In asymptomatic IPAA patients with an anatomically normal pouch, we have proposed normal parameters for high-resolution ano-pouch manometry, time to balloon expulsion, pouch barostat, and MR defecography.

Amino-caprolactam γ-secretase inhibitors showing potential for the treatment of Alzheimer's disease.

Herein we describe the structure-activity relationship (SAR) of amino-caprolactam analogs derived from amino-caprolactam benzene sulfonamide 1, highlighting affects on the potency of γ-secretase inhibition, selectivity for the inhibition of APP versus Notch processing by γ-secretase and selected pharmakokinetic properties. Amino-caprolactams that are efficacious in reducing the cortical Aß(x-40) levels in FVB mice via a single 100 mpk IP dose are highlighted.