Complete Tracheal Ring Deformity. A Translational Genomics Approach to Pathogenesis.

Rationale: Complete tracheal ring deformity (CTRD) is a rare congenital abnormality of unknown etiology characterized by circumferentially continuous or nearly continuous cartilaginous tracheal rings, variable degrees of tracheal stenosis and/or shortening, and/or pulmonary arterial sling anomaly.Objectives: To test the hypothesis that CTRD is caused by inherited or de novo mutations in genes required for normal tracheal development.Methods: CTRD and normal tracheal tissues were examined microscopically to define the tracheal abnormalities present in CTRD. Whole-exome sequencing was performed in children with CTRD and their biological parents ("trio analysis") to identify gene variants in patients with CTRD. Mutations were confirmed by Sanger sequencing, and their potential impact on structure and/or function of encoded proteins was examined using human gene mutation databases. Relevance was further examined by comparison with the effects of targeted deletion of murine homologs important to tracheal development in mice.Measurements and Main Results: The trachealis muscle was absent in all of five patients with CTRD. Exome analysis identified six de novo, three recessive, and multiple compound-heterozygous or rare hemizygous variants in children with CTRD. De novo variants were identified in SHH (Sonic Hedgehog), and inherited variants were identified in HSPG2 (perlecan), ROR2 (receptor tyrosine kinase-like orphan receptor 2), and WLS (Wntless), genes involved in morphogenetic pathways known to mediate tracheoesophageal development in mice.Conclusions: The results of the present study demonstrate that absence of the trachealis muscle is associated with CTRD. Variants predicted to cause disease were identified in genes encoding Hedgehog and Wnt signaling pathway molecules, which are critical to cartilage formation and normal upper airway development in mice.

Evaluation of the self-directed format of Walk With Ease in patients with systemic lupus erythematosus: the Walk-SLE Pilot Study.

OBJECTIVE: To conduct a proof-of-concept pilot evaluation of the self-directed format of Walk With Ease (WWE), a 6-week walking program developed for adults with arthritis, in patients with systemic lupus erythematosus (SLE). METHODS: This was a single arm, 6-week pre- and post-evaluation of the self-directed WWE program to assess feasibility, tolerability, safety, acceptability, and effectiveness. Adult patients with physician-diagnosed SLE were recruited to participate during regularly scheduled visits to an academic rheumatology clinic. Self-reported outcomes of pain, stiffness, and fatigue were assessed by visual analog scales (VAS) and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-fatigue) scale at baseline and at completion of the 6-week program. Patients also completed a satisfaction survey at the end of the program. Multivariate linear regression models were used to calculate mean changes between baseline and 6-week follow-up scores, adjusting for covariates. Mean change scores were used to estimate effect sizes (ES). RESULTS: At 6 weeks, 48 of the 75 recruited participants completed the WWE program. Participants experienced modest improvements in stiffness and fatigue (ES = 0.12 and ES = 0.23, respectively, for VAS scores; ES = 0.16 for FACIT-fatigue score) following the intervention. The majority of participants reported satisfaction with the program (98%) and benefitted from the workbook (96%). CONCLUSIONS: The self-directed format of WWE appears to reduce stiffness and fatigue in patients with SLE. It also seems to be a feasible and acceptable exercise program to patients with SLE. Larger studies are needed to confirm these findings.

Evaluation of cephalexin failure rates in morbidly obese patients with cellulitis.

WHAT IS KNOWN AND OBJECTIVE: Identification of adequate antimicrobial dosing regimens for morbidly obese patients is essential given the simultaneous increase in morbid obesity and cellulitis prevalence in recent years. Insufficient data currently exist to describe the effectiveness of extrapolating traditional antibiotic dosing strategies to morbidly obese patients with cellulitis. The primary objective of this study was to compare therapeutic failure rates in non-obese and morbidly obese patients with cellulitis when treated with cephalexin at standard dosing. METHODS: This was a single-centre, retrospective cohort analysis. Adult patients hospitalized or under inpatient observation at a 1265-bed academic medical centre who received cephalexin monotherapy for non-purulent cellulitis from 2005 to 2015 were evaluated for inclusion. Patients were divided into two cohorts based on body mass index (BMI), where BMI <30 kg/m(2) was defined as non-obese and BMI ≥40 kg/m(2) as morbidly obese. Patients with critical risk factors for purulent or polymicrobial cellulitis were excluded. The primary outcome, therapeutic failure, was defined as a need for extended or additional antimicrobial therapy, surgical intervention, emergency department visit, or re-hospitalization within two to thirty days after cephalexin initiation. RESULTS AND DISCUSSION: A total of 94 patients (69 non-obese and 25 morbidly obese) met inclusion and exclusion criteria, which was below the estimated sample size needed to reach desired power. The rate of therapeutic failure in the morbidly obese group was similar to the non-obese group (20% vs. 14·5%, P = 0·53). Patients most commonly had extended or additional antibiotics prescribed in response to therapeutic failure with cephalexin. WHAT IS NEW AND CONCLUSION: Cephalexin failure rates for cellulitis did not differ statistically between morbidly obese and non-obese patients. The underpowered nature of this study is a limitation. Until further study with a larger sample size is completed, empiric adjustment of cephalexin dosing based solely on BMI may not be necessary.

Novel associations between FAAH genetic variants and postoperative central opioid-related adverse effects.

Opioid effects are potentiated by cannabinoid agonists including anandamide, an endocannabinoid. Inter-individual variability in responses to opioids is a major clinical problem. Multiple deaths and anoxic brain injuries occur every year because of opioid-induced respiratory depression (RD) in surgical patients and drug abusers of opioids and cannabinoids. This study aimed to determine specific associations between genetic variants of fatty acid amide hydrolase (FAAH) and postoperative central opioid adverse effects in children undergoing tonsillectomy. This is a prospective genotype-blinded observational study in which 259 healthy children between 6 and 15 years of age who received standard perioperative care with a standard anesthetic and an intraoperative dose of morphine were enrolled. Associations between frequent polymorphisms of FAAH and central postoperative opioid adverse effects including, RD, postoperative nausea and vomiting (PONV) and prolonged stay in Post Anesthesia Recovery Room (postoperative anesthesia care unit, PACU) due to RD and PONV were analyzed. Five specific FAAH single nucleotide polymorphisms (SNPs) had significant associations with more than twofold increased risk for refractory PONV (adjusted P<0.0018), and nominal associations (P<0.05) with RD and prolonged PACU stay in white children undergoing tonsillectomy. The FAAH SNP, rs324420, is a missense mutation with altered FAAH function and it is linked with other FAAH SNPs associated with PONV and RD in our cohort; association between PONV and rs324420 was confirmed in our extended cohort with additional 66 white children. Specific FAAH polymorphisms are associated with refractory PONV, opioid-related RD, and prolonged PACU stay due to opioid adverse effects in white children undergoing tonsillectomy.

A comparison of glycaemic effects of sitagliptin and sulfonylureas in elderly patients with type 2 diabetes mellitus.

INTRODUCTION: In the USA, 45% of patients with type 2 diabetes mellitus (T2DM) are elderly (≥ 65 years old). In general, use of sulfonylurea increases with patient age as does the associated risk for hypoglycaemia, and the consequences of hypoglycaemia can be more pronounced in elderly patients. Sitagliptin, a DPP-4 inhibitor, improves glycaemic control in adult patients of all ages with T2DM, with a low risk of hypoglycaemia when used alone or in combination with other antidiabetic agents that are not generally associated with hypoglycaemia when used independently. METHODS: In a post hoc analysis, pooled data from elderly patients who participated in one of three double-blind studies comparing the effects of therapy with sitagliptin (100 mg/day) vs. sulfonylurea (in titrated doses) were analysed for changes from baseline in HbA1c, fasting plasma glucose (FPG), and body weight and for the incidence of reported symptomatic hypoglycaemia. In these studies, patients on diet alone or metformin were randomised to sitagliptin or glipizide for 104 weeks (studies 1 and 2) or glimepiride for 30 weeks (study 3). The analysis included 372 elderly patients who completed a trial through 25 or 30 weeks. RESULTS: Both HbA1c and FPG decreased from baseline with each treatment, with no statistically significant differences between treatments. A significantly lower incidence of reported hypoglycaemia was observed with sitagliptin compared with sulfonylurea (6.2% vs. 27.8%; p < 0.001). Body weight decreased significantly with sitagliptin but not with sulfonylurea. Significantly more patients on sitagliptin than on sulfonylureas achieved a composite end-point of >0.5% HbA1c reduction with no reported hypoglycaemia or increase in body weight (44.1% vs. 16.0%; p < 0.001). CONCLUSION: In this analysis of elderly patients with T2DM, compared with sulfonylurea, sitagliptin provided similar glycaemic efficacy with less hypoglycaemia and with body weight loss.

Efficacy and safety of initial combination treatment with sitagliptin and pioglitazone--a factorial study.

AIM: To evaluate the efficacy and safety of initial combination therapy of sitagliptin 100 mg/day coadministered with all marketed doses of pioglitazone in patients with type 2 diabetes. METHODS: Patients with A1c ≥7.5 and ≤11.0% were randomized among seven arms that received, once daily, 100 mg sitagliptin alone; 15, 30 or 45 mg pioglitazone alone, or 100 mg sitagliptin plus 15, 30 or 45 mg pioglitazone for 54 weeks. The primary endpoint was change from baseline in A1c at week 24. Protocol-specified analyses compared combination therapies with monotherapies at respective dose-strengths and combination of sitagliptin plus pioglitazone 30 mg with pioglitazone 45 mg monotherapy. Post-hoc analyses compared sitagliptin plus pioglitazone 15 mg with pioglitazone monotherapy at the two higher doses. RESULTS: Initial combination therapy with sitagliptin and pioglitazone provided significantly greater reductions in A1c (0.4-0.7% differences) and other glycaemic endpoints than either monotherapy at the same doses. Combining sitagliptin with low-dose pioglitazone generally produced greater glycaemic improvements than higher doses of pioglitazone monotherapy (0.3-0.4% differences in A1c). Combination therapy was generally well tolerated; adverse events (AEs) of hypoglycaemia were reported with similar incidence (7.8-11.1%) in all treatment groups over the 54 weeks of study; oedema was reported in 0.5% of patients in the sitagliptin monotherapy group and 2.7-5.3% among pioglitazone-treated groups. Significant weight gain was observed in all combination-treated groups compared with the sitagliptin monotherapy group. CONCLUSIONS: Initial combination therapy with sitagliptin and pioglitazone provided better glycaemic control than either monotherapy and was generally well tolerated.

Sitagliptin and pioglitazone provide complementary effects on postprandial glucose and pancreatic islet cell function.

AIMS: The effects of sitagliptin and pioglitazone, alone and in combination, on α- and ß-cell function were assessed in patients with type 2 diabetes. METHODS: Following a 6-week diet/exercise period, 211 patients with HbA1c of 6.5-9.0% and fasting plasma glucose of 7.2-14.4 mmol/l were randomized (1 :1 :1 : 1) to sitagliptin, pioglitazone, sitagliptin + pioglitazone or placebo. At baseline and after 12 weeks, patients were given a mixed meal followed by frequent blood sampling for measurements of glucose, insulin, C-peptide and glucagon. RESULTS: After 12 weeks, 5-h glucose total area under the curve (AUC) decreased in all active treatments versus placebo; reduction with sitagliptin + pioglitazone was greater versus either monotherapy. The 5-h insulin total AUC increased with sitagliptin versus all other treatments and increased with sitagliptin + pioglitazone versus pioglitazone. The 3-h glucagon AUC decreased with sitagliptin versus placebo and decreased with sitagliptin + pioglitazone versus pioglitazone or placebo. Φ(s), a measure of dynamic ß-cell responsiveness to above-basal glucose concentrations, increased with either monotherapy versus placebo and increased with sitagliptin + pioglitazone versus either monotherapy. The insulin sensitivity index (ISI), a composite index of insulin sensitivity, improved with pioglitazone and sitagliptin + pioglitazone versus placebo. The disposition index, a measure of the relationship between ß-cell function and insulin sensitivity, improved with all active treatments versus placebo. CONCLUSIONS: Sitagliptin and pioglitazone enhanced ß-cell function (increasing postmeal Φ(s)), and sitagliptin improved α-cell function (decreasing postmeal glucagon) after 12 weeks in patients with type 2 diabetes. Through these complementary mechanisms of action, the combination of sitagliptin and pioglitazone reduced postmeal glucose more than either treatment alone.

Role of MYH9 and APOL1 in African and non-African populations with lupus nephritis.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by autoantibody production and organ damage. Lupus nephritis (LN) is one of the most severe manifestations of SLE. Multiple studies reported associations between renal diseases and variants in the non-muscle myosin heavy chain 9 (MYH9) and the neighboring apolipoprotein L 1 (APOL1) genes. We evaluated 167 variants spanning MYH9 for association with LN in a multiethnic sample. The two previously identified risk variants in APOL1 were also tested for association with LN in European-Americans (EAs) (N = 579) and African-Americans (AAs) (N = 407). Multiple peaks of association exceeding a Bonferroni corrected P-value of P < 2.03 × 10(-3) were observed between LN and MYH9 in EAs (N = 4620), with the most pronounced association at rs2157257 (P = 4.7 × 10(-4), odds ratio (OR) = 1.205). A modest effect with MYH9 was also detected in Gullah (rs8136069, P = 0.0019, OR = 2.304). No association between LN and MYH9 was found in AAs, Asians, Amerindians or Hispanics. This study provides the first investigation of MYH9 in LN in non-Africans and of APOL1 in LN in any population, and presents novel insight into the potential role of MYH9 in LN in EAs.

A functional haplotype of UBE2L3 confers risk for systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease with diverse clinical manifestations characterized by the development of pathogenic autoantibodies manifesting in inflammation of target organs such as the kidneys, skin and joints. Genome-wide association studies have identified genetic variants in the UBE2L3 region that are associated with SLE in subjects of European and Asian ancestry. UBE2L3 encodes an ubiquitin-conjugating enzyme, UBCH7, involved in cell proliferation and immune function. In this study, we sought to further characterize the genetic association in the region of UBE2L3 and use molecular methods to determine the functional effect of the risk haplotype. We identified significant associations between variants in the region of UBE2L3 and SLE in individuals of European and Asian ancestry that exceeded a Bonferroni-corrected threshold (P<1 × 10(-4)). A single risk haplotype was observed in all associated populations. Individuals harboring the risk haplotype display a significant increase in both UBE2L3 mRNA expression (P=0.0004) and UBCH7 protein expression (P=0.0068). The results suggest that variants carried on the SLE-associated UBE2L3 risk haplotype influence autoimmunity by modulating UBCH7 expression.

Identification of novel coding mutation in C1qA gene in an African-American pedigree with lupus and C1q deficiency.

OBJECTIVES: Homozygous C1q deficiency is an extremely rare condition and strongly associated with systemic lupus erythematosus. To assess and characterize C1q deficiency in an African-American lupus pedigree, C1q genomic region was evaluated in the lupus cases and family members. METHODS: Genomic DNA from patient was obtained and C1q A, B and C gene cluster was sequenced using next generation sequencing method. The identified mutation was further confirmed by direct Sanger sequencing method in the patient and all blood relatives. C1q levels in serum were measured using sandwich ELISA method. RESULTS: In an African-American patient with lupus and C1q deficiency, we identified and confirmed a novel homozygote start codon mutation in C1qA gene that changes amino acid methionine to arginine at position 1. The Met1Arg mutation prevents protein translation (Met1Arg). Mutation analyses of the patient's family members also revealed the Met1Arg homozygote mutation in her deceased brother who also had lupus with absence of total complement activity consistent with a recessive pattern of inheritance. CONCLUSION: The identification of new mutation in C1qA gene that disrupts the start codon (ATG to AGG (Met1Arg)) has not been reported previously and it expands the knowledge and importance of the C1q gene in the pathogenesis of lupus especially in the high-risk African-American population.

Effect of initial combination therapy with sitagliptin and metformin on ß-cell function in patients with type 2 diabetes.

AIM: To examine the effect of sitagliptin and metformin, alone and in combination, on modelled parameters of ß-cell function in patients with type 2 diabetes. METHODS: The data used in the present analyses are from a 104-week study, which included a 24-week, placebo- and active controlled phase followed by a 30-week, active controlled, continuation phase and an additional 50-week, active controlled extension phase. Patients were randomised to one of six blinded treatments: sitagliptin 50 mg + metformin 1000 mg b.i.d., sitagliptin 50 mg + metformin 500 mg b.i.d., metformin 1000 mg b.i.d., metformin 500 mg b.i.d., sitagliptin 100 mg q.d. or placebo. Patients on placebo were switched in a blinded manner to metformin 1000 mg b.i.d. at week 24. Subsets of patients volunteered to undergo frequently sampled meal tolerance tests at baseline and at weeks 24, 54 and 104. ß-cell responsivity was assessed with the C-peptide minimal model. The static component (Φ(s)) estimates the rate of insulin secretion related to above-basal glucose concentration. The dynamic component (Φ(d)) is related to the rate of change in glucose. The total index (Φ(total)) represents the overall response to a glycaemic stimulus and is calculated as a function of Φ(s) and Φ(d). Insulin sensitivity was estimated with the Matsuda index (ISI). The disposition index, which assesses insulin secretion relative to the prevailing insulin sensitivity, was calculated based on the Φ(total) and ISI. RESULTS: At week 24, substantial reductions in postmeal glucose were observed with all active treatment groups relative to the placebo group. Φ(s), Φ(total) and the disposition index were significantly improved from baseline at week 24 with all active treatments relative to placebo. Generally larger effects were observed with the initial combination of sitagliptin and metformin relative to the monotherapy groups. When expressed as median percent change from baseline, Φ(s) increased from baseline by 137 and 177% in the low- and high-dose combination groups and by 85, 54, 73 and -9% in the high-dose metformin, low-dose metformin, sitagliptin monotherapy and placebo groups, respectively. At weeks 54 and 104, the combination treatment groups continued to demonstrate greater improvements in ß-cell function relative to their respective monotherapy groups. CONCLUSIONS: After 24 weeks of therapy, relative to placebo, initial treatment with sitagliptin or metformin monotherapy improved ß-cell function; moreover, initial combination therapy demonstrated larger improvements than the individual monotherapies. Improvements in ß-cell function were found with treatments for up to 2 years.

Efficacy and safety of initial combination therapy with sitagliptin and pioglitazone in patients with type 2 diabetes: a 54-week study.

AIM: To assess the 54-week efficacy of initial combination therapy with sitagliptin and pioglitazone, compared with pioglitazone monotherapy, and to assess safety in these groups during the 30 weeks after the dosage of pioglitazone was increased from 30 to 45 mg/day, in drug-naÏve patients with type 2 diabetes mellitus and inadequate glycaemic control [haemoglobin A1c (HbA1c) 8-12%]. METHODS: Following a 24-week, randomized, double-blind, parallel-group study (Sitagliptin Protocol 064, Clinicaltrials.gov: NCT00397631; Yoon KH, Shockey GR, Teng R et al. Effect of initial combination therapy with sitagliptin, a dipeptidyl peptidase-4 inhibitor, and pioglitazone on glycaemic control and measures of beta-cell function in patients with type 2 diabetes. Int J Clin Pract 2011; 65: 154-164) in which patients were treated with the combination of sitagliptin 100 mg/day and pioglitazone 30 mg/day or monotherapy with pioglitazone 30 mg/day, patients entered a 30-week extension study. In the extension study, the pioglitazone dose was increased from 30 to 45 mg/day in both groups. Depending upon treatment allocation, patients took one tablet of sitagliptin 100 mg or matching placebo daily. Pioglitazone was administered in an open-label fashion as a single 45-mg tablet taken once daily. Patients not meeting specific glycaemic goals in the extension study were rescued with metformin therapy. Efficacy and safety results for the extension study excluded data after initiation of rescue therapy. RESULTS: Of the 520 patients initially randomized, 446 completed the base study and, of these, 317 entered the extension. In this extension study cohort, the mean reductions from baseline in HbA1c and fasting plasma glucose (FPG) at the end of the base study (week 24) were -2.5% and -62.1 mg/dl with the combination of sitagliptin 100 mg and pioglitazone 30 mg versus -1.9% and -48.7 mg/dl with pioglitazone monotherapy. At the end of the extension study (week 54), the mean reduction in haemoglobin A1c (HbA1c) was -2.4% with the combination of sitagliptin 100 mg and pioglitazone 45 mg versus -1.9% with pioglitazone monotherapy [between-group difference (95% CI) = -0.5% (-0.8, -0.3)] and the mean reduction in FPG was -61.3 mg/dl versus -52.8 mg/dl, respectively [between-group difference (95% CI) = -8.5 mg/dl (-16.3, -0.7)]. Safety and tolerability of initial treatment with the combination of sitagliptin and pioglitazone and pioglitazone monotherapy were similar. As expected, increases in body weight from baseline were observed in both treatment groups at week 54: 4.8 and 4.1 kg in the combination and monotherapy groups, respectively [between-group difference (95% CI) = 0.7 kg (-0.7, 2.1)]. CONCLUSION: In this study, initial combination therapy with sitagliptin 100 mg and pioglitazone 30 mg increased to 45 mg after 24 weeks led to a substantial and durable incremental improvement in glycaemic control compared with initial treatment with pioglitazone monotherapy during a 54-week treatment period. Both initial combination therapy with sitagliptin and pioglitazone and pioglitazone monotherapy were generally well tolerated (Clinicaltrials.gov: NCT01028391).

Initial therapy with the fixed-dose combination of sitagliptin and metformin results in greater improvement in glycaemic control compared with pioglitazone monotherapy in patients with type 2 diabetes.

AIMS: To evaluate the efficacy and safety of initial therapy with a fixed-dose combination (FDC) of sitagliptin and metformin compared with pioglitazone in drug-naÏve patients with type 2 diabetes. METHODS: After a 2-week single-blind placebo run-in period, patients with type 2 diabetes, HbA1c of 7.5-12% and not on antihyperglycaemic agent therapy were randomized in a double-blind manner to initial treatment with a FDC of sitagliptin/metformin 50/500 mg twice daily (N = 261) or pioglitazone 30 mg per day (N = 256). Sitagliptin/metformin and pioglitazone were up-titrated over 4 weeks to doses of 50/1000 mg twice daily and 45 mg per day, respectively. Both treatments were then continued for an additional 28 weeks. RESULTS: From a mean baseline HbA1c of 8.9% in both groups, least squares (LS) mean changes in HbA1c at week 32 were -1.9 and -1.4% for sitagliptin/metformin and pioglitazone, respectively (between-group difference = -0.5%; p < 0.001). A greater proportion of patients had an HbA1c of <7% at week 32 with sitagliptin/metformin vs. pioglitazone (57% vs. 43%, p < 0.001). Compared with pioglitazone, sitagliptin/metformin treatment resulted in greater LS mean reductions in fasting plasma glucose (FPG) [-56.0 mg/dl (-3.11 mmol/l) vs. -44.0 mg/dl (-2.45 mmol/l), p < 0.001] and in 2-h post-meal glucose [-102.2 mg/dl (-5.68 mmol/l) vs. -82.0 mg/dl (-4.56 mmol/l), p < 0.001] at week 32. A substantially greater reduction in FPG [-40.5 mg/dl (-2.25 mmol/l) vs. -13.0 mg/dl (-0.72 mmol/l), p < 0.001] was observed at week 1 with sitagliptin/metformin vs. pioglitazone. A greater reduction in the fasting proinsulin/insulin ratio and a greater increase in homeostasis model assessment of ß-cell function (HOMA-ß) were observed with sitagliptin/metformin than with pioglitazone, while greater decreases in fasting insulin and HOMA of insulin resistance (HOMA-IR), and a greater increase in quantitative insulin sensitivity check index (QUICKI) were observed with pioglitazone than with sitagliptin/metformin. Both sitagliptin/metformin and pioglitazone were generally well tolerated. Sitagliptin/metformin led to weight loss (-1.4 kg), while pioglitazone led to weight gain (3.0 kg) (p < 0.001 for the between-group difference). Higher incidences of diarrhoea (15.3% vs. 4.3%, p < 0.001), nausea (4.6% vs. 1.2%, p = 0.02) and vomiting (1.9% vs. 0.0%, p = 0.026), and a lower incidence of oedema (1.1% vs. 7.0%, p < 0.001), were observed with sitagliptin/metformin vs. pioglitazone. The between-group difference in the incidence of hypoglycaemia did not reach statistical significance (8.4 and 4.3% with sitagliptin/metformin and pioglitazone, respectively; p = 0.055). CONCLUSION: Compared with pioglitazone, initial therapy with a FDC of sitagliptin and metformin led to significantly greater improvement in glycaemic control as well as a higher incidence of prespecified gastrointestinal adverse events, a lower incidence of oedema and weight loss vs. weight gain.

Evaluation of the TREX1 gene in a large multi-ancestral lupus cohort.

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disorder with a complex pathogenesis in which genetic, hormonal and environmental factors have a role. Rare mutations in the TREX1 gene, the major mammalian 3'-5' exonuclease, have been reported in sporadic SLE cases. Some of these mutations have also been identified in a rare pediatric neurological condition featuring an inflammatory encephalopathy known as Aicardi-Goutières syndrome (AGS). We sought to investigate the frequency of these mutations in a large multi-ancestral cohort of SLE cases and controls. A total of 40 single-nucleotide polymorphisms (SNPs), including both common and rare variants, across the TREX1 gene, were evaluated in ∼8370 patients with SLE and ∼7490 control subjects. Stringent quality control procedures were applied, and principal components and admixture proportions were calculated to identify outliers for removal from analysis. Population-based case-control association analyses were performed. P-values, false-discovery rate q values, and odds ratios (OR) with 95% confidence intervals (CI) were calculated. The estimated frequency of TREX1 mutations in our lupus cohort was 0.5%. Five heterozygous mutations were detected at the Y305C polymorphism in European lupus cases but none were observed in European controls. Five African cases incurred heterozygous mutations at the E266G polymorphism and, again, none were observed in the African controls. A rare homozygous R114H mutation was identified in one Asian SLE patient, whereas all genotypes at this mutation in previous reports for SLE were heterozygous. Analysis of common TREX1 SNPs (minor allele frequency (MAF)>10%) revealed a relatively common risk haplotype in European SLE patients with neurological manifestations, especially seizures, with a frequency of 58% in lupus cases compared with 45% in normal controls (P=0.0008, OR=1.73, 95% CI=1.25-2.39). Finally, the presence or absence of specific autoantibodies in certain populations produced significant genetic associations. For example, a strong association with anti-nRNP was observed in the European cohort at a coding synonymous variant rs56203834 (P=2.99E-13, OR=5.2, 95% CI=3.18-8.56). Our data confirm and expand previous reports and provide additional support for the involvement of TREX1 in lupus pathogenesis.

Effects of an 11ß-hydroxysteroid dehydrogenase type 1 inhibitor, MK-0916, in patients with type 2 diabetes mellitus and metabolic syndrome.

AIM: We examined the effects of the 11ß-hydroxysteroid dehydrogenase type 1 (HSD1) inhibitor, MK-0916, on the multiple components of the metabolic syndrome (MetS) in patients with type 2 diabetes (T2DM) and MetS. METHODS: This was a 12-week, multicentre, randomized, double-blind, placebo-controlled study. Patients with T2DM (mean baseline A1C: 7.3%) and National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III)-defined MetS were randomized 1 : 1 : 1 : 1 to 0.5, 2 or 6 mg/day MK-0916 or placebo. The primary efficacy endpoint was a change from baseline at week 12 in fasting plasma glucose (FPG). Secondary endpoints included glycosylated haemoglobin A(1c) (A1C), 2-h postprandial glucose (2-h PPG), body weight, waist circumference, blood pressure and lipid profile. RESULTS: Treatment with MK-0916 had no significant effect relative to placebo on FPG at week 12. Compared to placebo, 6 mg MK-0916 produced a modest, significant (p = 0.049) reduction in A1C of 0.3% at week 12, but no significant difference was observed in 2-h PPG. Six milligram MK-0916 increased LDL-C relative to placebo by 10.4% (p = 0.041). Treatment with MK-0916 led to modest dose-dependent decreases in blood pressure and body weight. Overall, MK-0916 was generally well tolerated. MK-0916 produced mechanism-based activation of the hypothalamic-pituitary-adrenal axis, resulting in mean increases in adrenal androgen levels that remained within the normal range at all doses tested. CONCLUSIONS: Inhibition of HSD1 with MK-0916 was generally well tolerated in patients with T2DM and MetS. Although no significant improvement in FPG was observed with MK-0916 compared to placebo, modest improvements in A1C, body weight and blood pressure were observed.

The effect of initial therapy with the fixed-dose combination of sitagliptin and metformin compared with metformin monotherapy in patients with type 2 diabetes mellitus.

AIMS: This study was conducted to compare the glycaemic efficacy and safety of initial combination therapy with the fixed-dose combination of sitagliptin and metformin versus metformin monotherapy in drug-naive patients with type 2 diabetes. METHODS: This double-blind study (18-week Phase A and 26-week Phase B) randomized 1250 drug-naÏve patients with type 2 diabetes [mean baseline haemoglobin A1c (HbA1c) 9.9%] to sitagliptin/metformin 50/500 mg bid or metformin 500 mg bid (uptitrated over 4 weeks to achieve maximum doses of sitagliptin/metformin 50/1000 mg bid or metformin 1000 bid). Results of the primary efficacy endpoint (mean HbA1c reductions from baseline at the end of Phase A) are reported herein. RESULTS: At week 18, mean change from baseline HbA1c was -2.4% for sitagliptin/metformin FDC and -1.8% for metformin monotherapy (p < 0.001); more patients treated with sitagliptin/metformin FDC had an HbA1c value <7% (p < 0.001) versus metformin monotherapy. Changes in fasting plasma glucose were significantly greater with sitagliptin/metformin FDC (-3.8 mmol/l) versus metformin monotherapy (-3.0 mmol/l; p < 0.001). Homeostasis model assessment of ß-cell function (HOMA-ß) and fasting proinsulin/insulin ratio were significantly improved with sitagliptin/metformin FDC versus metformin monotherapy. Baseline body weight was reduced by 1.6 kg in each group. Both treatments were generally well tolerated with a low and similar incidence of hypoglycaemia. Abdominal pain (1.1 and 3.9%; p = 0.002) and diarrhoea (12.0 and 16.6%; p = 0.021) occurred significantly less with sitagliptin/metformin FDC versus metformin monotherapy; the incidence of nausea and vomiting was similar in both groups. CONCLUSION: Compared with metformin monotherapy, initial treatment with sitagliptin/metformin FDC provided superior glycaemic improvement with a similar degree of weight loss and lower incidences of abdominal pain and diarrhoea.

Efficacy and safety of treatment with sitagliptin or glimepiride in patients with type 2 diabetes inadequately controlled on metformin monotherapy: a randomized, double-blind, non-inferiority trial.

AIM: to evaluate the efficacy and safety of adding sitagliptin or glimepiride to the treatment regimen of patients with type 2 diabetes mellitus and inadequate glycaemic control on metformin monotherapy. METHODS: patients with type 2 diabetes and an HbA(1c) of 6.5-9.0% while on a stable dose of metformin (≥ 1500 mg/day) combined with diet and exercise for at least 12 weeks were randomized in a double-blind manner to receive either sitagliptin 100 mg daily (N = 516) or glimepiride (starting dose 1 mg/day and up-titrated, based upon patient's self-monitoring of blood glucose results, to a maximum dose of up to 6 mg/day) (N = 519) for 30 weeks. The primary analysis assessed whether sitagliptin is non-inferior to glimepiride in reducing HbA(1c) at week 30 (based on the criterion of having an upper bound of the 95% CI less than the prespecified non-inferiority bound of 0.4%). RESULTS: the mean baseline HbA(1c) was 7.5% in both the sitagliptin group (n = 443) and the glimepiride group (n = 436). After 30 weeks, the least squares (LS) mean change in HbA(1c) from baseline was -0.47% with sitagliptin and -0.54% with glimepiride, with a between-group difference (95% CI) of 0.07% (-0.03, 0.16). This result met the prespecified criterion for declaring non-inferiority. The percentages of patients with an HbA(1c) < 7.0% at week 30 were 52 and 60% in the sitagliptin and glimepiride groups, respectively. The LS mean change in fasting plasma glucose from baseline (95% CI) was -0.8 mmol/l (-1.0, -0.6) with sitagliptin and -1.0 mmol/l (-1.2, -0.8) with glimepiride, for a between-group difference (95% CI) of 0.2 mmol/l (-0.1, 0.4). The percentages of patients for whom hypoglycaemia was reported were 7% in the sitagliptin group and 22% in the glimepiride group (percentage-point difference = -15, p < 0.001). Relative to baseline, sitagliptin was associated with a mean weight loss (-0.8 kg), whereas glimepiride was associated with a mean weight gain (1.2 kg), yielding a between-group difference of -2.0 kg (p < 0.001). CONCLUSIONS: in patients with type 2 diabetes and inadequate glycaemic control on metformin monotherapy, the addition of sitagliptin or glimepiride led to similar improvement in glycaemic control after 30 weeks. Sitagliptin was generally well tolerated. Compared to treatment with glimepiride, treatment with sitagliptin was associated with a lower risk of hypoglycaemia and with weight loss versus weight gain (ClinicalTrials.gov: NCT00701090).

A treatment strategy implementing combination therapy with sitagliptin and metformin results in superior glycaemic control versus metformin monotherapy due to a low rate of addition of antihyperglycaemic agents.

AIMS: Combination therapy with sitagliptin and metformin has shown superior efficacy compared with metformin monotherapy. In this study, we compare two strategies: initial combination therapy with sitagliptin/metformin as a fixed-dose combination (FDC) and initial metformin monotherapy, with the option to add additional antihyperglycaemic agents (AHAs) in either treatment arm during the second phase of the study in order to reach adequate glycaemic control. METHODS: We evaluated the sitagliptin and metformin FDC compared with metformin monotherapy over 44 weeks in 1250 patients with type 2 diabetes mellitus in a two-part, double-blind, randomized, controlled clinical trial. The initial 18-week portion (Phase A) of this study in which additional AHAs were only allowed based on prespecified glycaemic criteria, has been previously reported. Here, we present results from the 26-week Phase B portion of the study during which double-blind study medication continued; however, unlike Phase A, during Phase B investigators were unmasked to results for haemoglobin A1C (HbA1c) and fasting plasma glucose (FPG) and directed to manage glycaemic control by adding incremental AHA(s) as deemed clinically appropriate. RESULTS: There were 1250 patients randomized in the study with 965 completing Phase A and continuing in Phase B. Among patients receiving sitagliptin/metformin FDC or metformin monotherapy, 8.8% and 16.7% received additional AHA therapy, respectively. Although glycaemic therapy in both groups was to have been managed to optimize HbA1c reductions with the option for investigators to supplement with additional AHAs during Phase B, patients randomized to initial therapy with sitagliptin/metformin FDC had larger reductions of HbA1c from baseline compared with patients randomized to initial metformin monotherapy [least squares (LS) mean change: -2.3% and -1.8% (p < 0.001 for difference) for sitagliptin/metformin FDC and metformin monotherapy groups, respectively]. A significantly larger reduction in FPG from baseline was observed in the sitagliptin/metformin FDC group compared with the metformin monotherapy group (p = 0.001). Significantly more patients in the sitagliptin/metformin FDC group had an HbA1c of less than 7.0% or less than 6.5% compared with those on metformin monotherapy. Both treatment strategies were generally well tolerated, with a low and similar incidence of hypoglycaemia in both groups and lower incidences of abdominal pain and diarrhoea in the sitagliptin/metformin FDC group compared with the metformin monotherapy group. CONCLUSIONS: A strategy initially implementing combination therapy with sitagliptin/metformin FDC was superior to a strategy initially implementing metformin monotherapy, even when accounting for the later addition of supplemental AHAs. Sitagliptin/metformin FDC was generally well tolerated.

Efficacy and safety of sitagliptin and the fixed-dose combination of sitagliptin and metformin vs. pioglitazone in drug-naïve patients with type 2 diabetes.

AIM: The efficacy and safety of sitagliptin (SITA) monotherapy and SITA/metformin (MET) vs. pioglitazone (PIO) were assessed in patients with type 2 diabetes and moderate-to-severe hyperglycaemia (A1C = 7.5-12.0%). METHODS: In an initial 12-week phase (Phase A), 492 patients were randomised 1 : 1 in a double-blind fashion to SITA (100 mg qd) or PIO (15 mg qd, up-titrated to 30 mg after 6 weeks). In Phase B (28 additional weeks), the SITA group was switched to SITA/MET (up-titrated to 50/1000 mg bid over 4 weeks) and the PIO group was up-titrated to 45 mg qd RESULTS: At the end of Phase A, mean changes from baseline were -1.0% and -0.9% for A1C; -26.6 mg/dl and -28.0 mg/dl for fasting plasma glucose; and -52.8 mg/dl and -50.1 mg/dl for 2-h post-meal glucose for SITA and PIO, respectively. At the end of Phase B, improvements in glycaemic parameters were greater with SITA/MET vs. PIO: -1.7% vs. -1.4% for A1C (p = 0.002); -45.8 mg/dl vs. -37.6 mg/dl for fasting plasma glucose (p = 0.03); -90.3 mg/dl vs. -69.1 mg/dl for 2-h postmeal glucose (p = 0.001); and 55.0% vs. 40.5% for patients with A1C < 7% (p = 0.004). A numerically higher incidence of gastrointestinal adverse events and a significantly lower incidence of oedema were observed with SITA/MET vs. PIO. The incidence of hypoglycaemia was similarly low in both groups. Body weight decreased with SITA/MET and increased with PIO (-1.1 kg vs. 3.4 kg; p < 0.001). CONCLUSION: Improvements in glycaemic control were greater with SITA/MET vs. PIO, with weight loss vs. weight gain. Both treatments were generally well tolerated.

Effect of initial combination therapy with sitagliptin, a dipeptidyl peptidase-4 inhibitor, and pioglitazone on glycemic control and measures of ß-cell function in patients with type 2 diabetes.

AIM/HYPOTHESIS: To assess the safety and efficacy of initial combination therapy with sitagliptin and pioglitazone compared with pioglitazone monotherapy in drug-naïve patients with type 2 diabetes. METHODS: A total of 520 patients were randomised to initial combination therapy with sitagliptin 100 mg q.d. and pioglitazone 30 mg q.d. or pioglitazone 30 mg q.d. monotherapy for 24 weeks. RESULTS: Initial combination therapy with sitagliptin and pioglitazone led to a mean reduction from baseline in A1C of -2.4% compared with -1.5% for pioglitazone monotherapy (p<0.001). Mean reductions from baseline were greater in patients with a baseline A1C≥10% (-3.0% with combination therapy vs. -2.1% with pioglitazone monotherapy) compared with patients with a baseline A1C<10% (-2.0% with combination therapy vs. -1.1% with pioglitazone monotherapy). Sixty percent of patients in the combination therapy group vs. 28% in the pioglitazone monotherapy group had an A1C of <7% at week 24 (p<0.001). Fasting plasma glucose decreased by -63.0 mg/dl (-3.5 mmol/l) in the combination therapy group compared with -40.2 mg/dl (-2.2 mmol/l) for pioglitazone monotherapy (p<0.001), and 2-h post meal glucose decreased by -113.6 mg/dl (-6.3 mmol/l) with combination therapy compared with -68.9 mg/dl (-3.8 mmol/l) for pioglitazone monotherapy (p<0.001). Measures related to ß-cell function also improved significantly with combination therapy compared with pioglitazone monotherapy. Combination therapy was generally well-tolerated compared with pioglitazone monotherapy, with similar incidences of hypoglycemia (1.1% and 0.8%, respectively), gastrointestinal adverse events (5.7% and 6.9%, respectively), and oedema (2.7% and 3.5%, respectively). CONCLUSION/INTERPRETATION: Initial combination therapy with sitagliptin and pioglitazone substantially improved glycemic control and was generally well-tolerated compared with pioglitazone monotherapy.