Multiple switching between the biosimilar adalimumab PF-06410293 and reference adalimumab in patients with active rheumatoid arthritis: a phase 3, open-label, randomised, parallel-group study.

BACKGROUND: An adalimumab biosimilar with an interchangeability designation could increase access to effective treatment for more patients. We aimed to assess the interchangeability of adalimumab biosimilar PF-06410293 (adalimumab-afzb) and reference adalimumab using a multi-switch study design. METHODS: We did an open-label, randomised, parallel-group study at 61 community (n=29), hospital (n=12), and academic (n=20) sites in ten countries (Bulgaria, Bosnia and Herzegovina, Czech Republic, Lithuania, Poland, Russia, Serbia, South Africa, Ukraine, and USA). Eligible patients were aged 18-70 years and met the 2010 American College of Rheumatology-European League Against Rheumatism classification criteria for rheumatoid arthritis for at least 4 months with moderately to severely active rheumatoid arthritis, based on their physician's evaluation. Eligible patients had been receiving methotrexate for at least 12 weeks and been on a stable dose for at least 4 weeks before the first dose of study medication. All patients received subcutaneous reference adalimumab (40 mg/0·4 mL [100 mg/mL] every 2 weeks) for 10 weeks before randomisation. At week 10, patients were randomly assigned (1:1) to either three switches between subcutaneous reference adalimumab (40 mg/0·4 mL [100 mg/mL] every 2 weeks) and adalimumab-afzb (40 mg/0·8 mL [50 mg/mL] every 2 weeks; switching group), or continuous dosing with subcutanous reference adalimumab (40 mg/0·4 mL [100 mg/mL] every 2 weeks; non-switching group) with stratification by bodyweight groups. Patients, investigators, and site personnel were not masked to treatment allocation. Primary endpoints were maximum observed serum concentration (Cmax) and area under plasma concentration-time curve (AUCτ) during weeks 30-32 in the pharmacokinetic population. Interchangeability was based on geometric mean ratios and corresponding 90% CIs within prespecified equivalence margins of 80-125% for both primary endpoints. Safety was analysed in all patients who received at least one dose of adalimumab-afzb or reference adalimumab. This trial is registered with ClinicalTrials.gov, NCT04230213. FINDINGS: Of the 569 patients assessed for eligibility between Jan 13, 2020, and June 22, 2021, 445 were enrolled, and 427 completed the first 10 weeks and were randomly assigned (213 to the switching group and 214 to the non-switching group). Participants had a median age of 56 years (IQR 46-63), 354 (83%) of 427 patients were women and 73 (17%) were men, and 422 (99%) were White. In the pharmacokinetic population (n=380), no clinically meaningful differences were observed in mean steady-state pharmacokinetic parameters between the switching and non-switching groups (geometric mean AUC 2237 µg × h/mL in the switching group and 2125 µg × h/mL in the non-switching group; Cmax 8·21 µg/mL in the switching group and 8·00 µg/mL in the non-switching group). Geometric mean ratios and 90% CIs for AUCτ (105·31, 89·16-124·39) and Cmax (102·56, 89·78-117·17) were within prespecified equivalence margins. No meaningful differences were observed in the proportion of patients who had serious adverse events (three [1%] of 213 patients in the switching group vs eight [4%] of 214 patients in the non-switching group), grade 3 or higher adverse events of special interest, discontinuations due to adverse events (eight [4%] vs nine [4%]), or immunogenic reactions in antidrug antibody-positive patients. No deaths were reported during the study. INTERPRETATION: The risk of multiple switches between reference adalimumab and adalimumab-afzb with respect to diminished efficacy (using pharmacokinetics as a surrogate) or safety is not greater than the risk of using reference adalimumab alone. FUNDING: Pfizer. VIDEO ABSTRACT.

Use of multibiomarker disease activity scores in biosimilarity studies for the treatment of patients with rheumatoid arthritis.

OBJECTIVES: This exploratory analysis investigated the potential use of the multibiomarker disease activity (MBDA) score to support biosimilarity assessments using data from two randomised controlled trials (RCTs) of biosimilar infliximab (IFX-qbtx) and biosimilar adalimumab (ADL-afzb) versus EU-sourced infliximab (Remicade; IFX-EU) and adalimumab (Humira; ADL-EU) reference products, respectively, both conducted in adult patients with active rheumatoid arthritis. METHODS: In one study, patients (N=650) were randomised 1:1 to IFX-qbtx or IFX-EU (3 mg/kg intravenous at weeks 0, 2 and 6, then every 8 weeks). In the other, patients (N=597) were randomised 1:1 to ADL-afzb or ADL-EU (40 mg subcutaneous every other week). All treatments were given with MTX. Mean values of MBDA scores were calculated at baseline (BL), based on the concentrations of 12 serum proteins using the Vectra disease activity algorithm, and at timepoints throughout treatment period 1 (TP1) of the IFX (weeks 6, 14, 30) and ADL (weeks 6, 12, 26) studies. Data were summarised using descriptive statistics for the intent-to-treat population, without imputation for missing data. RESULTS: At BL, mean (±SD) MBDA scores were 61.3 (±12.5) and 58.8 (±13.2) for IFX-qbtx (n=236) and IFX-EU (n=248), respectively, and 57.2 (±14.44) and 58.3 (±15.34) for ADL-afzb (n=292) and ADL-EU (n=293), respectively. Mean MBDA scores were highly comparable between IFX-qbtx and IFX-EU and between ADL-afzb and ADL-EU at all measured timepoints during TP1 in each study. CONCLUSIONS: These RCTs are the first to incorporate MBDA score as an exploratory assessment of biosimilarity. MBDA scores may provide objective, quantitative evidence of biosimilarity using an assessment of disease activity that is independent of the potential subjectivity inherent in joint counts, or in patient or physician global assessments. TRIAL REGISTRATION NUMBERS: NCT02222493 and NCT02480153.

Usability Study of PF-06410293, an Adalimumab Biosimilar, by Prefilled Pen: Open-Label, Single-Arm, Sub-Study of a Phase 3 Trial in Patients with Rheumatoid Arthritis.

INTRODUCTION: The aim of this sub-study was to evaluate injection success of patients with rheumatoid arthritis (RA) and their caregivers administering the adalimumab (ADL) biosimilar, PF-06410293 (ADL-PF: adalimumab-afzb; Abrilada®/Amsparity®/Xilbrilada®) by prefilled pen (PFP) during the open-label treatment period in year two (weeks 52-78) of a phase 3 multinational, double-blind, clinical study (NCT02480153) comparing ADL-PF and reference ADL (Humira®) sourced from the EU. METHODS: This sub-study included adult patients with active RA not adequately controlled by methotrexate. Patients received subcutaneous ADL-PF 40 mg by prefilled syringe (PFS) at weeks 52 and 54, then six biweekly doses (weeks 56-66) of ADL-PF 40 mg each via a single-use PFP device. Training was given on first injection at week 56; all injections were given by patients/caregivers. The primary endpoint was delivery system success rate (DSSR): the percentage of participants (i.e., actual PFP user) achieving delivery success for each of the six attempted PFP injections. Injection success was recorded by the observer (Observer Assessment Tool) and participant (Participant Assessment Tool). RESULTS: In total, 50 patients with no experience self-injecting with an autoinjector/injection pen were included (74.0% female; mean age at screening, 54.9 years; mean RA duration, 8.0 years). Of these, 49 (98.0%) completed the sub-study and 46 (92.0%) received all six PFP injections. Overall DSSR (n = 294 injections) across visits was 100% (95% CI 92.0-100.0%). Complete injection was confirmed following inspection of 292 used and returned PFPs. A total of 47/49 (95.9%) participants who completed the sub-study elected to continue study treatment using PFP injections, rather than switching back to the PFS. CONCLUSIONS: All actual PFP users could safely and effectively administer ADL-PF by PFP at each visit, and nearly all participants who completed the sub-study elected to continue study treatment using PFP injections. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02480153; EudraCT number: 2014-000352-29.

Long-term efficacy, safety, and immunogenicity of the adalimumab biosimilar, PF-06410293, in patients with rheumatoid arthritis after switching from reference adalimumab (Humira®) or continuing biosimilar therapy: week 52-92 data from a randomized, double-blind, phase 3 trial.

BACKGROUND/OBJECTIVE: REFLECTIONS B538-02 is a randomized, double-blind comparative study of the adalimumab (ADL) biosimilar PF-06410293, (ADL-PF), and reference ADL sourced from the European Union (ADL-EU) in patients with active RA. Therapeutic equivalence was demonstrated based on ACR20 responses at week 12 (primary endpoint). We report long-term safety, immunogenicity, and efficacy of ADL-PF in patients who continued ADL-PF treatment throughout 78 weeks or who switched from ADL-EU to ADL-PF at week 26 or week 52. METHODS: Eligible patients (2010 ACR/EULAR RA diagnosis criteria for ≥ 4 months; inadequate response to MTX, ≤ 2 doses non-ADL biologic), stratified by geographic regions were initially randomized (1:1) in treatment period 1 (TP1) to ADL-PF or ADL-EU (40 mg subcutaneously, biweekly), both with MTX (10-25 mg/week). At week 26 (start of TP2), patients receiving ADL-EU were re-randomized to remain on ADL-EU or transition to ADL-PF for 26 weeks. At week 52 (start of TP3), all patients received open-label treatment with ADL-PF for 26 weeks and were followed after last treatment dose to week 92. To evaluate maintenance of response after switching or remaining on ADL-PF, ACR20, DAS28-4(CRP), and other measures of clinical response/remission were assessed through week 78 as secondary endpoints. Three groups were evaluated: biosimilar, week 26 switch, and week 52 switch. RESULTS: Overall, 507 patients participated in TP3. ACR20 response rates at week 52 were 88.4%, 88.2%, and 87.6% for the biosimilar, week 26, and week 52 switch groups, respectively. ACR20 response rates and DAS28-4(CRP) scores were sustained and comparable across groups in TP3. Incidence of treatment-emergent adverse events (AEs) during TP3 and follow-up was 42.6% (biosimilar), 37.0% (week 26 switch), and 50.8% (week 52 switch); 3 (0.6%) patients (all week 52 switch) reported treatment-related serious AEs. ADL-PF was generally well tolerated, with a comparable safety profile across groups. Overall, incidences of patients with anti-drug antibodies in TP3 and follow-up were comparable among groups (46.1%, 46.5%, and 54.2%, respectively). CONCLUSIONS: There were no clinically meaningful differences in safety, immunogenicity, and efficacy for patients who were maintained on ADL-PF for 78 weeks and those who had switched from ADL-EU at week 26 or week 52. TRIAL REGISTRATION: ClinicalTrials.gov , NCT02480153. First posted on June 24, 2015; EU Clinical Trials Register; EudraCT number: 2014-000352-29. Start date, October 27, 2014.

Randomised study of PF-06410293, an adalimumab (ADL) biosimilar, compared with reference ADL for the treatment of active rheumatoid arthritis: results from weeks 26-52, including a treatment switch from reference ADL to PF-06410293.

OBJECTIVE: To investigate the efficacy, safety, immunogenicity and pharmacokinetics of biosimilar adalimumab (ADL) PF-06410293 (ADL-PF; adalimumab-afzb) versus EU-sourced reference ADL (ADL-EU) in patients with active rheumatoid arthritis (RA) on longer-term treatment and after being switched from ADL-EU to ADL-PF. METHODS: In this multinational, double-blind study, patients with active RA were initially randomised to ADL-PF or ADL-EU for 26 weeks (treatment period (TP) 1). At the start of TP2 (weeks 26-52), patients in the ADL-EU arm were blindly re-randomised 1:1 to remain on ADL-EU (ADL-EU/ADL-EU; n=135) or switched to ADL-PF (ADL-EU/ADL-PF; n=134); patients receiving ADL-PF continued blinded treatment (ADL-PF/ADL-PF; n=283). RESULTS: The American College of Rheumatology 20% improvement (ACR20) response rates were comparable between treatment groups at all visits during TP2. At week 52, ACR20 response rates were 82.7% (ADL-PF/ADL-PF), 79.3% (ADL-EU/ADL-EU) and 84.3% (ADL-EU/ADL-PF). Other measures of deep response (ACR50/70, ACR/EULAR-defined remission, EULAR good response, and Disease Activity Score in 28 Joints Based on High-Sensitivity C-Reactive Protein <2.6) and Health Assessment Questionnaire-Disability Index were maintained over TP2 and comparable between groups. Treatment-emergent adverse events were reported in 43.5% (ADL-PF/ADL-PF), 44.4% (ADL-EU/ADL-EU) and 38.3% (ADL-EU/ADL-PF) of patients; there were no clinically meaningful differences in the safety profiles between groups. The percentage of patients who were antidrug antibody positive was comparable overall among ADL-PF/ADL-PF (47.3%), ADL-EU/ADL-EU (54.1%) and ADL-EU/ADL-PF (45.9%). CONCLUSIONS: The similar efficacy, safety, immunogenicity and pharmacokinetics of ADL-PF and ADL-EU, maintained up to week 52, were unaffected by blinded treatment switch from ADL-EU to ADL-PF at week 26. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier: NCT02480153; EudraCT number: 2014-000352-29.

A Divergent Route to Eravacycline.

A convergent route to eravacycline (1) has been developed by employing Michael-Dieckmann cyclization between enone 3 and a fully built and protected left-hand piece (LHP, 2). After construction of the core eravacycline structure, a deprotection reaction was developed, allowing for the isoxazole ring opening and global deprotection to be achieved in one pot. The LHP is synthesized from readily available 4-fluoro-3-methylphenol in six steps featuring a palladium-catalyzed phenyl carboxylation in the last step.

Comparison of paricalcitol with maxacalcitol injection in Japanese hemodialysis patients with secondary hyperparathyroidism.

Secondary hyperparathyroidism (SHPT) is one of the major complications of chronic kidney disease (CKD) and is associated with elevated serum intact parathyroid hormone (iPTH). Calcitriol, a non-selective vitamin D receptor agonist (VDRA) that suppresses iPTH is used for SHPT treatment, but its use is frequently complicated by hypercalcemia. Paricalcitol, a selective VDRA, demonstrated efficacy in iPTH suppression compared to maxacalcitol in a Phase 2 study (M11-609) in Japanese subjects. The current larger Phase 3 study (M11-517), evaluated the efficacy of intravenous paricalcitol injection compared to intravenous maxacalcitol injection with respect to iPTH and calcium control using a non-inferiority primary endpoint. In this double-blind, double-dummy, parallel-group study, eligible Japanese CKD subjects with SHPT on hemodialysis were randomized 1:1 to receive intravenous paricalcitol or intravenous maxacalcitol injections for 12 weeks. Dynamic allocation of subjects on the basis of screening iPTH levels was used to ensure equal distribution of subjects with iPTH <500 pg/mL and ≥500 pg/mL into the two treatment groups. 255 subjects were randomized to receive paricalcitol (N = 127) or maxacalcitol (N = 128). Primary efficacy analysis indicated that 27.7% in the paricalcitol group vs. 30.5% in the maxacalcitol group (95% CI -14.34% to 8.79%, P = 0.353) achieved target iPTH in the last 3 weeks without hypercalcemia during treatment, failing to achieve the non-inferiority margin of -5% that was set based upon agreement with the PMDA. Both intravenous paricalcitol and maxacalcitol were effective in reducing iPTH and provided similar safety profiles; however, non-inferiority for paricalcitol vs. maxacalcitol was not demonstrated.

Efficacy and safety evaluation of HSD-1 inhibitor ABT-384 in Alzheimer's disease.

BACKGROUND: In this study we assessed increased cortisol in Alzheimer's disease (AD) patients. The selective 11-ß-hydroxysteroid dehydrogenase type 1 (HSD-1) inhibitor ABT-384 blocked regeneration of active cortisol and this tests the hypothesis that intracellular hypercortisolism contributes to cognitive impairment. METHODS: In this double-blind, placebo- and active-controlled phase II study we examine the efficacy and safety of ABT-384 given 10 mg or 50 mg once daily, donepezil 10 mg once daily, or placebo for 12 weeks in subjects with mild-to-moderate AD. The primary efficacy end point was the change from baseline to final evaluation on the 13-item Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) total score. RESULTS: The study was terminated for futility after randomization of 267 subjects. ABT-384 did not improve ADAS-Cog scores or any secondary end point; however, donepezil significantly improved both cognition and functional end points. Overall incidence of adverse events was similar among treatment groups. CONCLUSION: ABT-384, when tested at doses associated with complete brain HSD-1 inhibition, did not produce symptomatic improvement in AD.

Synthesis and biological evaluation of 8-aminomethyltetracycline derivatives as novel antibacterial agents.

The C-8 position of the tetracyclines has been largely underexplored because of limitations in traditional semisynthetic techniques. Employing a total synthetic approach allowed for modifications at the C-7 and C-8 positions, enabling the generation of structure-activity relationships for overcoming the two most common tetracycline bacterial-resistance mechanisms: ribosomal protection (tet(M)) and efflux (tet(A)). Ultimately, several compounds were identified with balanced activity against both Gram-positive and Gram-negative bacteria, including pathogens bearing both types of tetracycline-resistance mechanisms. Compounds were screened in a murine systemic infection model to rapidly identify compounds with oral bioavailability, leading to the discovery of several compounds that exhibited efficacy when administered orally in murine pyelonephritis and pneumonia models.

Vitamin D reduces left atrial volume in patients with left ventricular hypertrophy and chronic kidney disease.

BACKGROUND: Left atrial enlargement, a sensitive integrator of left ventricular diastolic function, is associated with increased cardiovascular morbidity and mortality. Vitamin D is linked to lower cardiovascular morbidity, possibly modifying cardiac structure and function; however, firm evidence is lacking. We assessed the effect of an activated vitamin D analog on left atrial volume index (LAVi) in a post hoc analysis of the PRIMO trial (clinicaltrials.gov: NCT00497146). METHODS AND RESULTS: One hundred ninety-six patients with chronic kidney disease (estimated glomerular filtration rate 15-60 mL/min per 1.73 m(2)), mild to moderate left ventricular hypertrophy, and preserved ejection fraction were randomly assigned to 2 µg of oral paricalcitol or matching placebo for 48 weeks. Two-dimensional echocardiography was obtained at baseline and at 24 and 48 weeks after initiation of therapy. Over the study period, there was a significant decrease in LAVi (-2.79 mL/m(2), 95% CI -4.00 to -1.59 mL/m(2)) in the paricalcitol group compared with the placebo group (-0.70 mL/m(2) [95% CI -1.93 to 0.53 mL/m(2)], P = .002). Paricalcitol also attenuated the rise in levels of brain natriuretic peptide (10.8% in paricalcitol vs 21.3% in placebo, P = .02). For the entire population, the change in brain natriuretic peptide correlated with change in LAVi (r = 0.17, P = .03). CONCLUSIONS: Forty-eight weeks of therapy with an active vitamin D analog reduces LAVi and attenuates the rise of BNP. In a population where only few therapies alter cardiovascular related morbidity and mortality, these post hoc results warrant further confirmation.

Vitamin D therapy and cardiac structure and function in patients with chronic kidney disease: the PRIMO randomized controlled trial.

CONTEXT: Vitamin D is associated with decreased cardiovascular-related morbidity and mortality, possibly by modifying cardiac structure and function, yet firm evidence for either remains lacking. OBJECTIVE: To determine the effects of an active vitamin D compound, paricalcitol, on left ventricular mass over 48 weeks in patients with an estimated glomerular filtration rate of 15 to 60 mL/min/1.73 m(2). DESIGN, SETTING, AND PARTICIPANTS: Multinational, double-blind, randomized placebo-controlled trial among 227 patients with chronic kidney disease, mild to moderate left ventricular hypertrophy, and preserved left ventricular ejection fraction, conducted in 11 countries from July 2008 through September 2010. INTERVENTION: Participants were randomly assigned to receive oral paricalcitol, 2 µg/d (n =115), or matching placebo (n = 112). MAIN OUTCOME MEASURES: Change in left ventricular mass index over 48 weeks by cardiovascular magnetic resonance imaging. Secondary end points included echocardiographic changes in left ventricular diastolic function. RESULTS: Treatment with paricalcitol reduced parathyroid hormone levels within 4 weeks and maintained levels within the normal range throughout the study duration. At 48 weeks, the change in left ventricular mass index did not differ between treatment groups (paricalcitol group, 0.34 g/m(2.7) [95% CI, -0.14 to 0.83 g/m(2.7)] vs placebo group, -0.07 g/m(2.7) [95% CI, -0.55 to 0.42 g/m(2.7)]). Doppler measures of diastolic function including peak early diastolic lateral mitral annular tissue velocity (paricalcitol group, -0.01 cm/s [95% CI, -0.63 to 0.60 cm/s] vs placebo group, -0.30 cm/s [95% CI, -0.93 to 0.34 cm/s]) also did not differ. Episodes of hypercalcemia were more frequent in the paricalcitol group compared with the placebo group. CONCLUSION: Forty-eight week therapy with paricalcitol did not alter left ventricular mass index or improve certain measures of diastolic dysfunction in patients with chronic kidney disease. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00497146.

Fluorocyclines. 1. 7-fluoro-9-pyrrolidinoacetamido-6-demethyl-6-deoxytetracycline: a potent, broad spectrum antibacterial agent.

This and the accompanying report (DOI: 10.1021/jm201467r ) describe the design, synthesis, and evaluation of a new generation of tetracycline antibacterial agents, 7-fluoro-9-substituted-6-demethyl-6-deoxytetracyclines ("fluorocyclines"), accessible through a recently developed total synthesis approach. These fluorocyclines possess potent antibacterial activities against multidrug resistant (MDR) Gram-positive and Gram-negative pathogens. One of the fluorocyclines, 7-fluoro-9-pyrrolidinoacetamido-6-demethyl-6-deoxytetracycline (17j, also known as TP-434, 50th Interscience Conference on Antimicrobial Agents and Chemotherapy Conference , Boston, MA , September 12-15, 2010 , poster F1 - 2157 ), is currently undergoing phase 2 clinical trials in patients with complicated intra-abdominal infections (cIAI).

The use of group sequential, information-based sample size re-estimation in the design of the PRIMO study of chronic kidney disease.

BACKGROUND: Chronic kidney disease is associated with a marked increase in risk for left ventricular hypertrophy and cardiovascular mortality compared with the general population. Therapy with vitamin D receptor activators has been linked with reduced mortality in chronic kidney disease and an improvement in left ventricular hypertrophy in animal studies. PURPOSE: PRIMO (Paricalcitol capsules benefits in Renal failure Induced cardia MOrbidity) is a multinational, multicenter randomized controlled trial to assess the effects of paricalcitol (a selective vitamin D receptor activator) on mild to moderate left ventricular hypertrophy in patients with chronic kidney disease. METHODS: Subjects with mild-moderate chronic kidney disease are randomized to paricalcitol or placebo after confirming left ventricular hypertrophy using a cardiac echocardiogram. Cardiac magnetic resonance imaging is then used to assess left ventricular mass index at baseline, 24 and 48 weeks, which is the primary efficacy endpoint of the study. Because of limited prior data to estimate sample size, a maximum information group sequential design with sample size re-estimation is implemented to allow sample size adjustment based on the nuisance parameter estimated using the interim data. An interim efficacy analysis is planned at a pre-specified time point conditioned on the status of enrollment. The decision to increase sample size depends on the observed treatment effect. A repeated measures analysis model, using available data at Week 24 and 48 with a backup model of an ANCOVA analyzing change from baseline to the final nonmissing observation, are pre-specified to evaluate the treatment effect. Gamma-family of spending function is employed to control family-wise Type I error rate as stopping for success is planned in the interim efficacy analysis. LIMITATIONS: If enrollment is slower than anticipated, the smaller sample size used in the interim efficacy analysis and the greater percent of missing week 48 data might decrease the parameter estimation accuracy, either for the nuisance parameter or for the treatment effect, which might in turn affect the interim decision-making. CONCLUSIONS: The application of combining a group sequential design with a sample-size re-estimation in clinical trial design has the potential to improve efficiency and to increase the probability of trial success while ensuring integrity of the study.

Vitamin D receptor activation and left ventricular hypertrophy in advanced kidney disease.

BACKGROUND: In chronic kidney disease (CKD), left ventricular hypertrophy (LVH) is prevalent and is associated with increased cardiovascular morbidity and mortality. Vitamin D receptor (VDR) activation attenuates LVH progression in animal models. METHODS: PRIMO is a multinational, randomized, double-blinded trial with oral paricalcitol in subjects with stages 3-4 CKD, mild-to-moderate LVH and an LV ejection fraction >50%. The primary endpoint is change in the left ventricular mass index (LVMI) compared with placebo after 48 weeks of treatment. The main secondary endpoints are changes in diastolic function parameters. In this paper, we report baseline characteristics from this study. RESULTS: LVMI was 33.0 ± 7.5 g/m(2.7) for males and 30.8 ± 7.2 g/m(2.7) for females (p = 0.04). LVMI correlated with systolic blood pressure (r = 0.24), urine albumin creatinine ratio (r = 0.39), troponin T (r = 0.29), high-sensitivity C-reactive protein (r = 0.25) and plasma levels of B-type brain natriuretic peptide (r = 0.22); all p < 0.01. In multiple linear regression, each remained independently associated with LVMI. The early diastolic velocity of the lateral mitral annulus (E') was 8.1 ± 2.4 cm/s. E' was inversely correlated with age in univariate (r = -0.14, p = 0.04) and multivariable (p = 0.02) analysis. CONCLUSION: Among 227 multinational subjects with stages 3-4 CKD, baseline LVMI correlates with baseline blood pressure, urine albumin creatinine ratio and cardiac biomarkers, and baseline diastolic function correlates with age. This research was funded by Abbott Laboratories; ClinicalTrials.gov No. NCT00497146.

Pooling mRNA in microarray experiments and its effect on power.

MOTIVATION: Microarrays can simultaneously measure the expression levels of many genes and are widely applied to study complex biological problems at the genetic level. To contain costs, instead of obtaining a microarray on each individual, mRNA from several subjects can be first pooled and then measured with a single array. mRNA pooling is also necessary when there is not enough mRNA from each subject. Several studies have investigated the impact of pooling mRNA on inferences about gene expression, but have typically modeled the process of pooling as if it occurred in some transformed scale. This assumption is unrealistic. RESULTS: We propose modeling the gene expression levels in a pool as a weighted average of mRNA expression of all individuals in the pool on the original measurement scale, where the weights correspond to individual sample contributions to the pool. Based on these improved statistical models, we develop the appropriate F statistics to test for differentially expressed genes. We present formulae to calculate the power of various statistical tests under different strategies for pooling mRNA and compare resulting power estimates to those that would be obtained by following the approach proposed by Kendziorski et al. (2003). We find that the Kendziorski estimate tends to exceed true power and that the estimate we propose, while somewhat conservative, is less biased. We argue that it is possible to design a study that includes mRNA pooling at a significantly reduced cost but with little loss of information.

Comparison of methods for analysis of selective genotyping survival data.

Survival traits and selective genotyping datasets are typically not normally distributed, thus common models used to identify QTL may not be statistically appropriate for their analysis. The objective of the present study was to compare models for identification of QTL associated with survival traits, in particular when combined with selective genotyping. Data were simulated to model the survival distribution of a population of chickens challenged with Marek disease virus. Cox proportional hazards (CPH), linear regression (LR), and Weibull models were compared for their appropriateness to analyze the data, ability to identify associations of marker alleles with survival, and estimation of effects when all individuals were genotyped (full genotyping) and when selective genotyping was used. Little difference in power was found between the CPH and the LR model for low censoring cases for both full and selective genotyping. The simulated data were not transformed to follow a Weibull distribution and, as a result, the Weibull model generally resulted in less power than the other two models and overestimated effects. Effect estimates from LR and CPH were unbiased when all individuals were genotyped, but overestimated when selective genotyping was used. Thus, LR is preferred for analyzing survival data when the amount of censoring is low because of ease of implementation and interpretation. Including phenotypic data of non-genotyped individuals in selective genotyping analysis increased power, but resulted in LR having an inflated false positive rate, and therefore the CPH model is preferred for this scenario, although transformation of the data may also make the Weibull model appropriate for this case. The results from the research presented herein are directly applicable to interval mapping analyses.

Effects of an acetone extract of Boswellia carterii Birdw. (Burseraceae) gum resin on rats with persistent inflammation.

OBJECTIVE: Ruxiang, or Gummi olibanum, an herbal medicine derived from the gum resin of Boswellia carterii Birdw. (BC) of the family Burseraceae, has been used traditionally in China to alleviate pain and reduce inflammation. The present study is an investigation of the effects of a BC extract on persistent hyperalgesia and edema in rats with peripheral inflammation. DESIGN: In this randomized, blinded study, the antihyperalgesic and antiedema effects of 3 dosages of BC were compared to a vehicle control. Inflammation was induced in rats by injecting complete Freund's adjuvant (CFA) into one hind paw. A single oral dose of the BC extract was administered daily for 7 days, beginning one day before CFA. Hyperalgesia was assessed using a paw withdrawal latency (PWL) test pre-CFA and 2 hours, 5 hours, 1 day, and 5 days post-CFA. Edema was determined by measuring paw thickness at the same time points. Spinal Fos protein expression was analyzed 2 hours post-CFA. Adverse effects of the extract were monitored by observing the animals closely for unusual behavioral changes. RESULTS: Compared to control, a dosage of 0.45 g/kg BC significantly lengthened PWL and reduced paw edema on day 5 post-CFA. At 0.90 g/kg, BC significantly lengthened PWL at 5 hours, 1 day, and 5 days, and reduced paw edema at 2 hours, 5 hours, 1 day, and 5 days. This dosage also significantly suppressed spinal Fos expression in the medial half of laminae I-II. At 1.80 g/kg, BC significantly lengthened PWL and reduced paw edema at all time points. No noticeable adverse effects were observed in animals given the lower dosages of BC, but adverse effects in some animals were observed at 1.80 g/kg per day. In the acute toxicity study, the maximal single dose of 2.50 g/kg produced no adverse effects in the treated rats during the 14 days of observation. CONCLUSIONS: The data suggest that BC produces significant antihyperalgesia and anti-inflammation effects and that the antihyperalgesia may be mediated by suppressed inflammation-induced Fos expression in the spinal dorsal horn neurons.