Safety and Efficacy of Efruxifermin in Combination With a GLP-1 Receptor Agonist in Patients With NASH/MASH and Type 2 Diabetes in a Randomized Phase 2 Study.

BACKGROUND & AIMS: In phase 2 studies, efruxifermin, an Fc-FGF21 analog, significantly reduced steatohepatitis and fibrosis in patients with non-alcoholic steatohepatitis, now called metabolic dysfunction-associated steatohepatitis (MASH), for which there is no approved treatment. Type 2 diabetes (T2D) and obesity are prevalent among patients with MASH and increasingly treated with glucagon-like peptide-1 receptor agonists (GLP-1RAs). This study evaluated the safety and efficacy of efruxifermin in patients with MASH, fibrosis, and T2D taking a GLP-1RA. METHODS: Cohort D was a double-blind, placebo-controlled, phase 2b study in adults with T2D and MASH with fibrosis (F1-F3) on stable GLP-1RA therapy randomized (2:1) to receive efruxifermin 50 mg or placebo, once weekly for 12 weeks. The primary endpoint was safety and tolerability of efruxifermin added to a stable dose of GLP-1RA. Secondary endpoints included changes in hepatic fat fraction (HFF), markers of liver injury and fibrosis, and metabolic parameters. RESULTS: Adults (N = 31) with T2D and MASH fibrosis (F1-F3) on a stable GLP-1RA (semaglutide, 48.4%; dulaglutide, 45.2%; liraglutide, 6.5%) received efruxifermin 50 mg (n = 21) or placebo (n = 10) for 12 weeks. The addition of efruxifermin to a GLP-1RA appeared safe and well-tolerated. The most frequent efruxifermin-related adverse events were mild to moderate gastrointestinal events. One patient receiving efruxifermin discontinued due to nausea, and another withdrew consent. There were no treatment-related serious adverse events. After 12 weeks, efruxifermin reduced HFF by 65% (P < .0001 vs placebo) compared with a 10% reduction for placebo (GLP-1RA alone). Efruxifermin also improved noninvasive markers of liver injury, fibrosis, glucose, and lipid metabolism while maintaining GLP-1RA-mediated weight loss. CONCLUSIONS: The tolerability profile of efruxifermin added to GLP-1RA appeared comparable to that of either drug alone, while also significantly reducing HFF and noninvasive markers of fibrosis in patients with MASH and T2D. Liver health in patients already on a GLP-1RA may be further improved by addition of efruxifermin. CLINICALTRIALS: gov, Number: NCT05039450.

Safety and efficacy of once-weekly efruxifermin versus placebo in non-alcoholic steatohepatitis (HARMONY): a multicentre, randomised, double-blind, placebo-controlled, phase 2b trial.

BACKGROUND: Fibroblast growth factor 21 (FGF21) regulates metabolism and protects cells against stress. Efruxifermin is a bivalent Fc-FGF21 analogue that replicates FGF21 agonism of fibroblast growth factor receptor 1c, 2c, or 3c. The aim of this phase 2b study was to assess its efficacy and safety in patients with non-alcoholic steatohepatitis (NASH) and moderate (F2) or severe (F3) fibrosis. METHODS: HARMONY is a multicentre, randomised, double-blind, placebo-controlled, 96-week, phase 2b trial that was initiated at 41 clinics in the USA. Adults with biopsy-confirmed NASH, defined by a non-alcoholic fatty liver disease activity score (NAS) of 4 or higher and scores of 1 or higher in each of steatosis, ballooning, and lobular inflammation, with histological stage F2 or F3 fibrosis, were randomly assigned (1:1:1), via an interactive response system, to receive placebo or efruxifermin (28 mg or 50 mg), subcutaneously once weekly. Patients, investigators, pathologists, site staff, and the sponsor were masked to group assignments during the study. The primary endpoint was the proportion of patients with improvement in fibrosis of at least 1 stage and no worsening of NASH, based on analyses of baseline and week 24 biopsies (liver biopsy analysis set [LBAS]). A sensitivity analysis evaluated the endpoint in the full analysis set (FAS), for which patients with missing biopsies were considered non-responders. This trial is registered with ClinicalTrials.gov, NCT04767529, and is ongoing. FINDINGS: Between March 22, 2021, and Feb 7, 2022, 747 patients were assessed for eligibility and 128 patients (mean age 54·7 years [SD 10·4]; 79 [62%] female and 49 male [38%]; 118 [92%] white; and 56 [41%] Hispanic or Latino) were enrolled and randomly assigned to receive placebo (n=43), efruxifermin 28 mg (n=42; two randomised patients were not dosed because of an administrative error), or efruxifermin 50 mg (n=43). In the LBAS (n=113), eight (20%) of 41 patients in the placebo group had an improvement in fibrosis of at least 1 stage and no worsening of NASH by week 24 versus 15 (39%) of 38 patients in the efruxifermin 28 mg group (risk ratio [RR] 2·3 [95% CI 1·1-4·8]; p=0·025) and 14 (41%) of 34 patients in the efruxifermin 50 mg group (2·2 [1·0-5·0]; p=0·036). Based on the FAS (n=128), eight (19%) of 43 patients in the placebo group met this endpoint versus 15 (36%) of 42 in the efruxifermin 28 mg group (RR 2·2 [95% CI 1·0-4·8]; p=0·033) and 14 (33%) of 43 in the efruxifermin 50 mg group (1·9 [0·8-4·3]; p=0·123). The most frequent efruxifermin-related adverse events were diarrhoea (16 [40%] of 40 patients in the efruxifermin 28 mg group and 17 [40%] of 43 patients in efruxifermin 50 mg group vs eight [19%] of 43 patients in the placebo group; all events except one were grade 1-2) and nausea (11 [28%] patients in the efruxifermin 28 mg group and 18 [42%] patients in the efruxifermin 50 mg group vs ten [23%] patients in the placebo group; all grade 1-2). Five patients (two in the 28 mg group and three in the 50 mg group) discontinued due to adverse events. Serious adverse events occurred in four patients in the 50 mg group; one was defined as drug related (ulcerative esophagitis in a participant with a history of gastro-oesophageal reflux disease). No deaths occurred. INTERPRETATION: Efruxifermin improved liver fibrosis and resolved NASH over 24 weeks in patients with F2 or F3 fibrosis, with acceptable tolerability, supporting further assessment in phase 3 trials. FUNDING: Akero Therapeutics.

An integrated analysis of fecal microbiome and metabolomic features distinguish non-cirrhotic NASH from healthy control populations.

BACKGROUND AND AIMS: There is great interest in identifying microbiome features as reliable noninvasive diagnostic and/or prognostic biomarkers for non-cirrhotic NASH fibrosis. Several cross-sectional studies have reported gut microbiome features associated with advanced NASH fibrosis and cirrhosis, where the most prominent features are associated with cirrhosis. However, no large, prospectively collected data exist establishing microbiome features that discern non-cirrhotic NASH fibrosis, integrate the fecal metabolome as disease biomarkers, and are unconfounded by BMI and age. APPROACH AND RESULTS: Results from shotgun metagenomic sequencing performed on fecal samples prospectively collected from 279 US patients with biopsy-proven NASH (F1-F3 fibrosis) enrolled in the REGENERATE I303 study were compared to those from 3 healthy control cohorts and integrated with the absolute quantification of fecal bile acids. Microbiota beta-diversity was different, and BMI- and age-adjusted logistic regression identified 12 NASH-associated species. Random forest prediction models resulted in an AUC of 0.75-0.81 in a receiver operator characteristic analysis. In addition, specific fecal bile acids were significantly lower in NASH and correlated with plasma C4 levels. Microbial gene abundance analysis revealed 127 genes increased in controls, many involving protein synthesis, whereas 362 genes were increased in NASH many involving bacterial environmental responses (false discovery rate < 0.01). Finally, we provide evidence that fecal bile acid levels may be a better discriminator of non-cirrhotic NASH versus health than either plasma bile acids or gut microbiome features. CONCLUSIONS: These results may have value as a set of baseline characteristics of non-cirrhotic NASH against which therapeutic interventions to prevent cirrhosis can be compared and microbiome-based diagnostic biomarkers identified.

A randomized, double-blind, placebo-controlled phase IIa trial of efruxifermin for patients with compensated NASH cirrhosis.

Background & Aims: Efruxifermin has shown clinical efficacy in patients with non-alcoholic steatohepatitis (NASH) and F1-F3 fibrosis. The primary objective of the BALANCED Cohort C was to assess the safety and tolerability of efruxifermin in patients with compensated NASH cirrhosis. Methods: Patients with NASH and stage 4 fibrosis (n = 30) were randomized 2:1 to receive efruxifermin 50 mg (n = 20) or placebo (n = 10) once-weekly for 16 weeks. The primary endpoint was safety and tolerability of efruxifermin. Secondary and exploratory endpoints included evaluation of non-invasive markers of liver injury and fibrosis, glucose and lipid metabolism, and changes in histology in a subset of patients who consented to end-of-study liver biopsy. Results: Efruxifermin was safe and well-tolerated; most adverse events (AEs) were grade 1 (n = 7, 23.3%) or grade 2 (n = 19, 63.3%). The most frequent AEs were gastrointestinal, including transient, mild to moderate diarrhea, and/or nausea. Significant improvements were noted in key markers of liver injury (alanine aminotransferase) and glucose and lipid metabolism. Sixteen-week treatment with efruxifermin was associated with significant reductions in non-invasive markers of fibrosis including Pro-C3 (least squares mean change from baseline [LSMCFB] -9 µg/L efruxifermin vs. -3.4 µg/L placebo; p = 0.0130) and ELF score (-0.4 efruxifermin vs. +0.4 placebo; p = 0.0036), with a trend towards reduced liver stiffness (LSMCFB -5.7 kPa efruxifermin vs. -1.1 kPa placebo; n.s.). Of 12 efruxifermin-treated patients with liver biopsy after 16 weeks, 4 (33%) achieved fibrosis improvement of at least one stage without worsening of NASH, while an additional 3 (25%) achieved resolution of NASH, compared to 0 of 5 placebo-treated patients. Conclusions: Efruxifermin appeared safe and well-tolerated with encouraging improvements in markers of liver injury, fibrosis, and glucose and lipid metabolism following 16 weeks of treatment, warranting confirmation in larger and longer term studies. Lay summary: Cirrhosis resulting from non-alcoholic steatohepatitis (NASH), the progressive form of non-alcoholic fatty liver disease, represents a major unmet medical need. Currently there are no approved drugs for the treatment of NASH. This proof-of-concept randomized, double-blind clinical trial demonstrated the potential therapeutic benefit of efruxifermin treatment compared to placebo in patients with cirrhosis due to NASH. Clinical Trial Number: NCT03976401.

Non-invasive evaluation of response to obeticholic acid in patients with NASH: Results from the REGENERATE study.

BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH) is a chronic, progressive fibrotic liver disease that can lead to cirrhosis. While liver biopsy is considered the reference standard for the histologic diagnosis of NASH and staging of fibrosis, its use in clinical practice is limited. Non-invasive tests (NITs) are increasingly being used to identify and stage liver fibrosis in patients with NASH, and several can assess liver-related outcomes. We report changes in various NITs in patients treated with obeticholic acid (OCA) or placebo in the phase III REGENERATE study. METHODS: Patients with NASH and fibrosis stage F2 or F3 (n = 931) were randomized (1:1:1) to receive placebo, OCA 10 mg, or OCA 25 mg once daily. Various NITs based on clinical chemistry and/or imaging were evaluated at baseline and throughout the study. RESULTS: Rapid, sustained reductions from baseline in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase levels, as well as in Fibrosis-4 (FIB-4), FibroTest, FibroMeter, and FibroScan-AST scores were observed in OCA-treated vs. placebo-treated patients. Reduction in liver stiffness by vibration-controlled transient elastography was observed in the OCA 25 mg group vs. the placebo group at Month 18. NIT changes were associated with shifts in histologic fibrosis stage. The greatest improvements were observed in patients with ≥1-stage fibrosis improvement; however, improvements in ALT, AST, FIB-4, and FibroTest were also observed in OCA-treated patients whose histologic fibrosis remained stable. CONCLUSIONS: Based on the REGENERATE Month 18 interim analysis, rapid and sustained improvements in various NITs were observed with OCA treatment. Dynamic changes in selected NITs separated histologic responders from non-responders. These results suggest that NITs may be useful in assessing histologic response to OCA therapy. CLINICALTRIALS. GOV NUMBER: NCT02548351 LAY SUMMARY: Non-alcoholic steatohepatitis (NASH) is a chronic, progressive liver disease that can lead to cirrhosis. To diagnose and assess liver fibrosis (scarring) in patients with NASH, non-invasive tests (NITs) are increasingly being used rather than liver biopsy, which is invasive, expensive, and can be risky. In the REGENERATE study, which is evaluating the effects of obeticholic acid vs. placebo in patients with NASH, various NITs were also evaluated. This analysis shows that improvements in levels of certain blood components, as well as favorable results of ultrasound imaging and proprietary tests of liver function, were associated with improvements in liver fibrosis after treatment with obeticholic acid, suggesting that NITs may be useful alternatives to liver biopsy in assessing NASH patients' response to therapy.

Obeticholic acid for the treatment of non-alcoholic steatohepatitis: interim analysis from a multicentre, randomised, placebo-controlled phase 3 trial.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a common type of chronic liver disease that can lead to cirrhosis. Obeticholic acid, a farnesoid X receptor agonist, has been shown to improve the histological features of NASH. Here we report results from a planned interim analysis of an ongoing, phase 3 study of obeticholic acid for NASH. METHODS: In this multicentre, randomised, double-blind, placebo-controlled study, adult patients with definite NASH, non-alcoholic fatty liver disease (NAFLD) activity score of at least 4, and fibrosis stages F2-F3, or F1 with at least one accompanying comorbidity, were randomly assigned using an interactive web response system in a 1:1:1 ratio to receive oral placebo, obeticholic acid 10 mg, or obeticholic acid 25 mg daily. Patients were excluded if cirrhosis, other chronic liver disease, elevated alcohol consumption, or confounding conditions were present. The primary endpoints for the month-18 interim analysis were fibrosis improvement (≥1 stage) with no worsening of NASH, or NASH resolution with no worsening of fibrosis, with the study considered successful if either primary endpoint was met. Primary analyses were done by intention to treat, in patients with fibrosis stage F2-F3 who received at least one dose of treatment and reached, or would have reached, the month 18 visit by the prespecified interim analysis cutoff date. The study also evaluated other histological and biochemical markers of NASH and fibrosis, and safety. This study is ongoing, and registered with ClinicalTrials.gov, NCT02548351, and EudraCT, 20150-025601-6. FINDINGS: Between Dec 9, 2015, and Oct 26, 2018, 1968 patients with stage F1-F3 fibrosis were enrolled and received at least one dose of study treatment; 931 patients with stage F2-F3 fibrosis were included in the primary analysis (311 in the placebo group, 312 in the obeticholic acid 10 mg group, and 308 in the obeticholic acid 25 mg group). The fibrosis improvement endpoint was achieved by 37 (12%) patients in the placebo group, 55 (18%) in the obeticholic acid 10 mg group (p=0·045), and 71 (23%) in the obeticholic acid 25 mg group (p=0·0002). The NASH resolution endpoint was not met (25 [8%] patients in the placebo group, 35 [11%] in the obeticholic acid 10 mg group [p=0·18], and 36 [12%] in the obeticholic acid 25 mg group [p=0·13]). In the safety population (1968 patients with fibrosis stages F1-F3), the most common adverse event was pruritus (123 [19%] in the placebo group, 183 [28%] in the obeticholic acid 10 mg group, and 336 [51%] in the obeticholic acid 25 mg group); incidence was generally mild to moderate in severity. The overall safety profile was similar to that in previous studies, and incidence of serious adverse events was similar across treatment groups (75 [11%] patients in the placebo group, 72 [11%] in the obeticholic acid 10 mg group, and 93 [14%] in the obeticholic acid 25 mg group). INTERPRETATION: Obeticholic acid 25 mg significantly improved fibrosis and key components of NASH disease activity among patients with NASH. The results from this planned interim analysis show clinically significant histological improvement that is reasonably likely to predict clinical benefit. This study is ongoing to assess clinical outcomes. FUNDING: Intercept Pharmaceuticals.

CONTROL: A randomized phase 2 study of obeticholic acid and atorvastatin on lipoproteins in nonalcoholic steatohepatitis patients.

BACKGROUND & AIMS: Nonalcoholic steatohepatitis (NASH) is a chronic and severe form of nonalcoholic fatty liver disease that can progress to cirrhosis and hepatocellular carcinoma and is a risk factor for cardiovascular disease. Although NASH has no approved treatments, obeticholic acid (OCA), a synthetic bile acid and farnesoid X receptor (FXR) agonist, was shown to improve histological features of NASH and fibrosis. Considering that FXR activation influences plasma lipoprotein concentrations, the Combination OCA aNd sTatins for monitoRing Of Lipids (CONTROL) study evaluated how statins can regulate lipoprotein metabolism with OCA treatment in patients with NASH. METHODS: This randomized, double-blind, placebo-controlled, phase 2 study began with a 5-week screening/statin washout; 84 patients with NASH were randomly assigned (1:1:1:1) to receive placebo or 5 mg, 10 mg or 25 mg OCA once daily during the 16-week double-blind phase. Concurrent once daily atorvastatin (10 mg/days) was initiated at Week 4 with subsequent titration. Enrolled patients had biopsy-confirmed diagnosis of NASH with no evidence of hepatic decompensation. Plasma was collected to analyse lipoprotein parameters. RESULTS: At Week 4, all OCA groups had an increase from baseline in mean low-density lipoprotein cholesterol (LDLc) and mean LDL particle concentration (LDLpc), mostly owing to large, less atherogenic LDLc particles. Atorvastatin 10 mg decreased LDLc and LDLpc levels below baseline in all OCA groups by Week 8; higher doses did not provide additional clinical benefits. CONCLUSIONS: The CONTROL study showed that OCA-induced increases in LDLc in patients with NASH were mitigated with atorvastatin. The combination of OCA and atorvastatin was generally safe and well tolerated (NCT02633956).

REGENERATE: Design of a pivotal, randomised, phase 3 study evaluating the safety and efficacy of obeticholic acid in patients with fibrosis due to nonalcoholic steatohepatitis.

BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a chronic, progressive, and severe form of nonalcoholic fatty liver disease. In FLINT, obeticholic acid (OCA) treatment improved multiple histological NASH features. The design and endpoints of REGENERATE, an ongoing phase 3 study, further evaluate OCA treatment in patients with fibrosis due to NASH. AIMS: The Month 18 interim analysis assesses the effect of OCA on liver histology, defined as improvement of fibrosis by ≥1 stage with no worsening of NASH or resolution of NASH with no worsening of fibrosis. The end-of-study analyses evaluate the effect of OCA on mortality, liver-related clinical outcomes, and long-term safety. METHODS: REGENERATE is a pivotal, long-term study of ~2400 patients with NASH, including ~2100 patients with stage 2 or 3 liver fibrosis. Additionally, ~300 patients with stage 1 fibrosis and ≥1 accompanying comorbidity are included to gather information on the safety of OCA and liver disease progression. Patients are randomised 1:1:1 to receive placebo or OCA (10 or 25 mg). A liver biopsy evaluation occurs at screening, Months 18 and 48, and end of study. The duration of the study is dependent upon accrual of a predetermined number of clinical outcome events. CONCLUSIONS: REGENERATE is designed in conjunction with regulatory authorities to support regulatory approvals in NASH. This robust phase 3 study assesses the effect of OCA on liver histology as a surrogate for transplant-free survival and liver-related outcomes, including progression to cirrhosis and mortality, and will ultimately assess clinical benefit through specific evaluation of these outcomes. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov with the identifier NCT02548351.

Factors Associated With Histologic Response in Adult Patients With Nonalcoholic Steatohepatitis.

BACKGROUND & AIMS: Nonalcoholic steatohepatitis (NASH) is a leading cause of liver transplantation, and many trials are underway to evaluate potential therapies. The farnesoid X receptor ligand obeticholic acid in the NASH treatment trial evaluated the effects of obeticholic acid vs placebo on histologic response (defined as decrease in nonalcoholic fatty liver disease activity score [NAS] by ≥2, with no worsening of fibrosis); 45% of patients had a histologic response to obeticholic acid (25 mg), and 21% had a response to placebo (P < .01). We performed a secondary analysis of data from this trial to identify clinical parameters associated with a histologic response. METHODS: We used a logistic regression model with a stepwise selection procedure to identify baseline and early on-treatment factors associated with a histologic response at 72 weeks. Baseline demographics, liver histology, medical history, concomitant medications, cardiometabolic parameters, and serum biochemistry, as well as the changes over the course of the trial (at weeks 12 and 24), were evaluated as potential predictors of a histologic response. The model was cross-validated by a jackknife method, and performance was evaluated with the area under the receiver operating characteristic curve. RESULTS: The logistic regression model found that obeticholic acid treatment, baseline NAS > 5, baseline triglyceride level ≤ 154 mg/dL, baseline international normalized ratio ≤ 1, baseline aspartate aminotransferase level ≤ 49 U/L, and a decrease in alanine aminotransferase level at week 24 by 17 U/L or more, to be significantly associated with histologic response (area under the receiver operating characteristic curve, 0.83; 95% confidence interval, 0.77-0.89; P < .0001). CONCLUSIONS: In a secondary analysis of data from a clinical trial of obeticholic acid in patients with NASH, we identified routine clinical and laboratory parameters during the first 24 weeks of treatment (such as baseline NAS, triglyceride levels, and a decrease in alanine aminotransferase level) to significantly associate with histologic markers of response.

Alosetron versus traditional pharmacotherapy in clinical practice: effects on resource use, health-related quality of life, safety and symptom improvement in women with severe diarrhea-predominant irritable bowel syndrome.

OBJECTIVE: Severe diarrhea-predominant irritable bowel syndrome (IBS-D) is associated with decreased health-related quality of life (HRQOL) and increased health care costs. Treatment recommendations for IBS-D often start with traditional pharmacotherapy (TP), with escalation to alosetron, rifaximin or eluxadoline if there is no success. There has been no previous head-to-head clinical trial comparing IBS-D treatment outcome for alosetron versus TP. This study, GSK protocol S3B30020, evaluated resource use, work productivity, health-related quality of life and global symptom response in women with IBS-D who were treated with alosetron or TP. METHODS: A total of 1956 patients who met criteria for severe IBS-D were randomized to treatment with alosetron 1 mg twice daily (BID) or only TP for up to 24 weeks. Work productivity and resource use were evaluated by standard questionnaires, HRQOL by the IBSQOL instrument and IBS symptoms by the Global Improvement Scale (GIS). RESULTS: Compared to only TP, alosetron-treated patients reported: (1) fewer clinic/office visits for any health problem (p = .0181) or for IBS-D (p = .0004); (2) reduced use of over-the-counter medications for IBS-D (p < .0001); (3) fewer days of lost work productivity (p < .0001); (4) decreased restriction of social and outdoor activities (p < .0001); and (5) greater global improvement in IBS-D symptoms (p < .0001). Alosetron treatment improved HRQOL scores for all domains (p < .0001). Incidence of adverse events during alosetron use was not remarkable and was similar to that previously reported. CONCLUSIONS: Alosetron 1 mg BID significantly reduced health care utilization and lost productivity, and significantly improved global IBS symptoms, HRQOL, and participation in outdoor and social activities compared with treatment response to TP.

Relationship between three commonly used non-invasive fibrosis biomarkers and improvement in fibrosis stage in patients with non-alcoholic steatohepatitis.

BACKGROUND & AIMS: Non-invasive biomarkers are needed for monitoring changes in liver histology in patients with non-alcoholic steatohepatitis (NASH). Obeticholic acid (OCA) was shown to improve fibrosis in patients with NASH in the FLINT trial; a post hoc analysis of these data was performed to determine the relationship between 3 non-invasive fibrosis markers and liver fibrosis improvement. METHODS: In the Phase 2b FLINT trial, patients were randomised (1:1) to receive 25 mg OCA or placebo once daily for 72 weeks. Aspartate aminotransferase:platelet ratio index (APRI), fibrosis-4 (FIB-4) index and non-alcoholic fatty liver disease fibrosis score (NFS) were evaluated in serum at baseline and weeks 24, 48, 72 and 96. Liver biopsies were obtained at baseline and 72 weeks. RESULTS: In patients with fibrosis improvement at week 24, scores were reduced by a median of 34% for APRI, 10% for FIB-4 and 4% for NFS. Reductions in APRI (P = 0.015) and FIB-4 (P = 0.036), but not NFS (P = 0.201) at week 24, significantly correlated with ≥1-stage improvement in histologic fibrosis at week 72. Reductions in APRI at week 72 were significantly correlated with fibrosis improvement at week 72 (P = 0.012). Patients receiving OCA had significant reductions in all markers compared with patients receiving placebo at week 72 [APRI and FIB-4 (P < 0.0001); NFS (P < 0.05)]. CONCLUSIONS: Readily available non-invasive markers may predict improvement in liver fibrosis in patients with NASH. Upon external confirmation and further refinement in larger populations, these markers may serve as surrogate endpoints in NASH clinical trials.

Targeting of rifamycin SV to the colon for treatment of travelers' diarrhea: a randomized, double-blind, placebo-controlled phase 3 study.

BACKGROUND: Rifamycin SV is under development for treatment of travelers' diarrhea (TD) in a new oral formulation, Rifamycin SV MMX (RIF-MMX; Santarus Inc., San Diego, CA, USA), which targets its delivery to the colon, making it a unique rifamycin drug. METHODS: This was a randomized, double-blind, phase 3 study of adult travelers to Mexico or Guatemala experiencing acute diarrhea. A total of 264 patients received RIF-MMX (2 × 200 mg twice daily for 3 days, n = 199) or placebo (n = 65) in a 3 : 1 ratio. The primary endpoint was the length of time between the administration of first dose of study drug and passage of the last unformed stool (TLUS; after which clinical cure was declared). Other endpoints included eradication of pathogens from the stools, pathogen minimum inhibitory concentration (MIC), and adverse events (AEs). RESULTS: TLUS was significantly shorter in the RIF-MMX group (median: 46.0 hours) compared with placebo (median: 68.0 hours; p = 0.0008) and a larger percentage of RIF-MMX treated patients (81.4%) achieved clinical cure compared with placebo patients (56.9%). TLUS was significantly shorter in the subgroups of patients with enteroaggregative, enterotoxigenic, or diffusely adherent Escherichia coli infections (p = 0.0035) with nonsignificant activity against invasive bacteria (p = 0.3804). Overall pathogen eradication rates were numerically higher in the RIF-MMX group (67.0%) compared with placebo (54.8%) but the difference did not reach significance (p = 0.0836). In vitro resistance to rifamycin SV was observed in some bacteria remaining after treatment of patients with RIF-MMX but was not associated with lower efficacy in them. AEs appeared to be more frequent with placebo (38.5%) than with RIF-MMX (29.6%). CONCLUSIONS: RIF-MMX shortened the duration of TD in patients with a broad range of pathogens and was well tolerated. The unique pharmacokinetic properties of the drug offer evidence that TD pathogens work at the level of the colon.

A 9-year evaluation of temporal trends in alosetron postmarketing safety under the risk management program.

OBJECTIVES: Adverse events (AEs) of ischemic colitis (IC) and complications of constipation (CoC) associated with alosetron are rare and have been adjudicated during the first 5.5 years of the risk management program (RMP); however, changes in incidence rates relative to reductions in AE reports and increases in alosetron prescriptions over the 9-year RMP have not been evaluated. The authors aim to evaluate temporal trends in alosetron postmarketing safety over the 9-year RMP. METHODS: The alosetron safety database was searched to identify cases of IC, CoC, and related AEs from 20 November 2002 to 31 December 2011. Adjudication of IC and CoC cases were based on US Food and Drug Administration-defined criteria. Incidence rates were calculated using the number of AEs and alosetron prescriptions (expressed as cases/1000 patient-years exposure). RESULTS: A total of 29 cases were adjudicated as probable/possible IC and 7 cases were adjudicated as CoC. Cumulative adjudicated incidence rate of IC (1.03 cases/1000 patient-years) is low and stable, while that of CoC (0.25 cases/1000 patient-years) is low, declining progressively over time. Decreases in the incidence rates of potential symptoms of IC (abdominal pain with bloody diarrhea/hematochezia) and CoC (constipation) were also observed. CONCLUSIONS: Over the 9-year RMP period, incidence rates of IC and CoC remain rare. Substantial reductions over time were observed in the incidence of CoC and in symptoms suggestive of IC or CoC, while IC incidence has been stable at approximately 1.0 case/1000 patient-years. Decreases in AEs and serious outcomes associated with IC and CoC since the reintroduction of alosetron are likely attributable to the RMP.

Monitoring of adalimumab and antibodies-to-adalimumab levels in patient serum by the homogeneous mobility shift assay.

This report describes the analytical validation and application of the homogeneous mobility shift assay (HMSA) method for the measurement of adalimumab and human antibodies-to-adalimumab (ATA) in serum samples from patients who have lost response to adalimumab treatment. Validation of the ATA- and the adalimumab-HMSA revealed a lower limit of detection to be 0.026 U/mL for ATA and 0.018 µg/mL for adalimumab in serum samples. Intra-assay and inter-assay precision determination yielded a coefficient of variation of less than 15%, and the accuracy of both assays was within 20%. Adalimumab drug tolerance in the ATA-HMSA was up to 20 µg/mL in the test serum. Serum samples from 100 drug-naïve healthy subjects were tested to set-up the cut point of 0.55 U/mL for ATA and 0.68 µg/mL for adalimumab. Analysis of 100 serum samples from patients who were losing response to adalimumab showed that 26% had an adalimumab level below the cut point, of these 68% were ATA positive. Overall, 44% of the patients (44/100) were positive for ATA. This study presents evidence that drug and anti-drug antibody levels are important determinants of patient response to therapy.

Enhanced weight loss with pramlintide/metreleptin: an integrated neurohormonal approach to obesity pharmacotherapy.

The neurohormonal control of body weight involves a complex interplay between long-term adiposity signals (e.g., leptin), and short-term satiation signals (e.g., amylin). In diet-induced obese (DIO) rodents, amylin/leptin combination treatment led to marked, synergistic, fat-specific weight loss. To evaluate the weight-lowering effect of combined amylin/leptin agonism (with pramlintide/metreleptin) in human obesity, a 24-week, randomized, double-blind, active-drug-controlled, proof-of-concept study was conducted in obese or overweight subjects (N = 177; 63% female; 39 +/- 8 years; BMI 32.0 +/- 2.1 kg/m(2); 93.3 +/- 13.2 kg; mean +/- s.d.). After a 4-week lead-in period with pramlintide (180 microg b.i.d. for 2 weeks, 360 microg b.i.d. thereafter) and diet (40% calorie deficit), subjects achieving 2-8% weight loss were randomized 1:2:2 to 20 weeks of treatment with metreleptin (5 mg b.i.d.), pramlintide (360 microg b.i.d.), or pramlintide/metreleptin (360 microg/5 mg b.i.d.). Combination treatment with pramlintide/metreleptin led to significantly greater weight loss from enrollment to week 20 (-12.7 +/- 0.9%; least squares mean +/- s.e.) than treatment with pramlintide (-8.4 +/- 0.9%; P < 0.001) or metreleptin (-8.2 +/- 1.3%; P < 0.01) alone (evaluable, N = 93). The greater reduction in body weight was significant as early as week 4, and weight loss continued throughout the study, without evidence of a plateau. The most common adverse events with pramlintide/metreleptin were injection site events and nausea, which were mostly mild to moderate and decreased over time. These results support further development of pramlintide/metreleptin as a novel, integrated neurohormonal approach to obesity pharmacotherapy.

Janus kinase inhibitor INCB20 has antiproliferative and apoptotic effects on human myeloma cells in vitro and in vivo.

Protein tyrosine kinases of the Janus kinase (JAK) family are associated with many cytokine receptors, which, on ligand binding, regulate important cellular functions such as proliferation, survival, and differentiation. In multiple myeloma, JAKs may be persistently activated due to a constant stimulation by interleukin (IL)-6, which is produced in the bone marrow environment. INCB20 is a synthetic molecule that potently inhibits all members of the JAK family with a 100- to 1,000-fold selectivity for JAKs over >70 other kinases. Treatment of multiple myeloma cell lines and patient tumor cells with INCB20 resulted in a significant and dose-dependent inhibition of spontaneous as well as IL-6-induced cell growth. Importantly, multiple myeloma cell growth was inhibited in the presence of bone marrow stromal cells. The IL-6 dependent cell line INA-6 was particularly sensitive to the drug (IC50<1 micromol/L). Growth suppression of INA-6 correlated with an increase in the percentage of apoptotic cells and inhibition of signal transducer and activator of transcription 3 phosphorylation. INCB20 also abrogated the protective effect of IL-6 against dexamethasone by blocking phosphorylation of SHP-2 and AKT. In contrast, AKT phosphorylation induced by insulin-like growth factor-I remained unchanged, showing selectivity of the compound. In a s.c. severe combined immunodeficient mouse model with INA-6, INCB20 significantly delayed INA-6 tumor growth. Our studies show that disruption of JAKs and downstream signaling pathways may both inhibit multiple myeloma cell growth and survival and overcome cytokine-mediated drug resistance, thereby providing the preclinical rationale for the use of JAK inhibitors as a novel therapeutic approach in multiple myeloma.

Gene expression analysis of B-lymphoma cells resistant and sensitive to bortezomib.

The proteasome inhibitor bortezomib has shown impressive clinical activity alone and in combination with conventional and other novel agents for the treatment of multiple myeloma (MM). Although bortezomib is known to be a selective proteasome inhibitor, the downstream mechanisms of cytotoxicity and drug resistance are poorly understood. However, resistance to bortezomib as a single agent develops in the majority of patients, and activity in other malignancies has been less impressive. To elucidate mechanisms of bortezomib resistance, we compared differential gene expression profiles of bortezomib-resistant SUDHL-4 and bortezomib-sensitive SUDHL-6 diffuse large B-cell lymphoma lines in response to bortezomib. At concentrations that effectively inhibited proteasome activity, bortezomib induced apoptosis in SUDHL-6 cells, but not in SUDHL-4 cells. We showed that overexpression of activating transcription factor 3 (ATF3), ATF4, ATF5, c-Jun, JunD and caspase-3 is associated with sensitivity to bortezomib-induced apoptosis, whereas overexpression of heat shock protein (HSP)27, HSP70, HSP90 and T-cell factor 4 is associated with bortezomib resistance.

Preferential degradation of oxidized proteins by the 20S proteasome may be inhibited in aging and in inflammatory neuromuscular diseases.

Free radicals produced by chronic inflammation cause cumulative damage to cellular macromolecules and appear to contribute to senescence/aging, age-related disorders, and neuromuscular degenerative diseases such as inclusion-body myositis. Proteins are major targets for oxidative damage (in addition to DNA and lipids) and the accumulation of oxidized proteins has been reported in many aging and disease models. In young and healthy individuals, moderately oxidized soluble cell proteins are selectively and rapidly degraded by the 20S proteasome. The mechanism of selective proteolysis appears to depend upon oxidation-induced protein unfolding, with increasing surface hydrophobicity as (previously shielded) hydrophobic residues are exposed from the interior. The 20S proteasome can preferentially bind to and degrade such mildly oxidized, hydrophobic proteins without a need for ubiquitin targeting or ATP activation. Severely oxidized, aggregated, and crosslinked proteins, however, are poor substrates for degradation and actually inhibit the proteasome. During aging, and in many age-related diseases/disorders, the proteasome is progressively inhibited by binding to increasing levels of oxidized and cross-linked protein aggregates. Cellular aging and inflammatory neuromuscular degenerative diseases probably include both an increase in the generation of reactive oxygen species as well as a decline in proteasome activity, resulting in the progressive accumulation of oxidatively damaged protein aggregates that eventually contribute to cellular dysfunction and senescence.

Antimyeloma activity of heat shock protein-90 inhibition.

We show that multiple myeloma (MM), the second most commonly diagnosed hematologic malignancy, is responsive to hsp90 inhibitors in vitro and in a clinically relevant orthotopic in vivo model, even though this disease does not depend on HER2/neu, bcr/abl, androgen or estrogen receptors, or other hsp90 chaperoning clients which are hallmarks of tumor types traditionally viewed as attractive clinical settings for use of hsp90 inhibitors, such as the geldanamycin analog 17-AAG. This class of agents simultaneously suppresses in MM cells the expression and/or function of multiple levels of insulin-like growth factor receptor (IGF-1R) and interleukin-6 receptor (IL-6R) signaling (eg, IKK/NF-kappaB, PI-3K/Akt, and Raf/MAPK) and downstream effectors (eg, proteasome, telomerase, and HIF-1alpha activities). These pleiotropic proapoptotic effects allow hsp90 inhibitors to abrogate bone marrow stromal cell-derived protection on MM tumor cells, and sensitize them to other anticancer agents, including cytotoxic chemotherapy and the proteasome inhibitor bortezomib. These results indicate that hsp90 can be targeted therapeutically in neoplasias that may not express or depend on molecules previously considered to be the main hsp90 client proteins. This suggests a more general role for hsp90 in chaperoning tumor- or tissue-type-specific constellations of client proteins with critical involvement in proliferative and antiapoptotic cellular responses, and paves the way for more extensive future therapeutic applications of hsp90 inhibition in diverse neoplasias, including MM.