Empirical hierarchical bayes approach to gene-environment interactions: development and application to genome-wide association studies of lung cancer in TRICL.

The analysis of gene-environment (G × E) interactions remains one of the greatest challenges in the postgenome-wide association studies (GWASs) era. Recent methods constitute a compromise between the robust but underpowered case-control and powerful case-only methods. Inferences of the latter are biased when the assumption of gene-environment (G-E) independence in controls fails. We propose a novel empirical hierarchical Bayes approach to G × E interaction (EHB-GE), which benefits from greater rank power while accounting for population-based G-E correlation. Building on Lewinger et al.'s ([2007] Genet Epidemiol 31:871-882) hierarchical Bayes prioritization approach, the method first obtains posterior G-E correlation estimates in controls for each marker, borrowing strength from G-E information across the genome. These posterior estimates are then subtracted from the corresponding case-only G × E estimates. We compared EHB-GE with rival methods using simulation. EHB-GE has similar or greater rank power to detect G × E interactions in the presence of large numbers of G-E correlations with weak to strong effects or only a low number of such correlations with large effect. When there are no or only a few weak G-E correlations, Murcray et al.'s method ([2009] Am J Epidemiol 169:219-226) identifies markers with low G × E interaction effects better. We applied EHB-GE and competing methods to four lung cancer case-control GWAS from the Interdisciplinary Research in Cancer of the Lung/International Lung Cancer Consortium with smoking as environmental factor. A number of genes worth investigating were identified by the EHB-GE approach.

A common MLP (muscle LIM protein) variant is associated with cardiomyopathy.

RATIONALE: We previously discovered the human 10T-->C (Trp4Arg) missense mutation in exon 2 of the muscle LIM protein (MLP, CSRP3) gene. OBJECTIVE: We sought to study the effects of this single-nucleotide polymorphism in the in vivo situation. METHODS AND RESULTS: We now report the generation and detailed analysis of the corresponding Mlp(W4R/+) and Mlp(W4R/W4R) knock-in animals, which develop an age- and gene dosage-dependent hypertrophic cardiomyopathy and heart failure phenotype, characterized by almost complete loss of contractile reserve under catecholamine induced stress. In addition, evidence for skeletal muscle pathology, which might have implications for human mutation carriers, was observed. Importantly, we found significantly reduced MLP mRNA and MLP protein expression levels in hearts of heterozygous and homozygous W4R-MLP knock-in animals. We also detected a weaker in vitro interaction of telethonin with W4R-MLP than with wild-type MLP. These alterations may contribute to an increased nuclear localization of W4R-MLP, which was observed by immunohistochemistry. CONCLUSIONS: Given the well-known high frequency of this mutation in Caucasians of up to 1%, our data suggest that (W4R-MLP) might contribute significantly to human cardiovascular disease.

Outcomes of the Pediatric Development Plan of Tapentadol.

The opioid analgesic tapentadol was the first pain medication to be developed for the treatment of pain in children under a formal process established by the regulatory authorities. This article summarizes the outcomes of the pediatric development program for tapentadol across the entire age range from birth (including neonates) to adolescents <18 years of age. In addition, the challenges experienced when designing and conducting the pediatric tapentadol clinical trials as well as the interactions with the regulatory authorities are discussed. As a first outcome, the oral solution of tapentadol was authorized in the EU in 2018 as a new treatment option in the hospital setting for moderate to severe acute pain in children from 2 to <18 years of age.

Bone fractures in patients using tapentadol or oxycodone: an exploratory US claims database study.

Aim: To explore fracture outcomes with tapentadol or oxycodone, two opioids with differing mechanisms of action. Materials & methods: Retrospective cohort pilot study, using MarketScan® Commercial and Medicare Supplemental claims databases, on patients with postoperative pain, back pain, or osteoarthritis and ≥1 claim for tapentadol (n = 16,457), oxycodone (n = 1,356,920), or both (n = 15,893) between June 2009 and December 2015. Results: During 266,826 and 9,007,889 days of tapentadol and oxycodone treatment, patients evidenced 1080 and 72,275 fractures, respectively. Fracture rates per treatment-year were 1.512 for tapentadol and 3.013 for oxycodone. Conclusion: Examination of administrative claims has inherent limitations, but this exploratory analysis indicates a lower fracture rate with tapentadol than oxycodone in the analyzed dataset, which needs confirmation by further clinical trials.

Tapentadol for the Treatment of Moderate-to-Severe Acute Pain in Children Under the Age of Two Years.

BACKGROUND: Pharmacokinetics (PK), efficacy, and safety of the opioid analgesic tapentadol in the treatment of moderate-to-severe acute pain have so far not been investigated in pediatric patients <2 years of age. PATIENTS AND METHODS: Two multicenter, open-label trials assessed the pharmacokinetic profile, safety, tolerability, and efficacy of single doses of tapentadol oral solution (OS; NCT02221674; n=19) or intravenous infusion (IV, EudraCT 2014-002259-24; n=38) in children from birth to <2 years of age. Of these, 8 preterm neonates were included in the IV trial. A third randomized, double-blind, placebo-controlled trial (NCT02081391) investigated the efficacy and safety of multiple tapentadol OS doses in patients from birth to <2 years (placebo n=4, tapentadol n=11) using an immediate rescue trial design. Patients in all three trials underwent surgery that, in the investigator's opinion, reliably produced moderate-to-severe pain requiring opioid treatment. RESULTS: Administration of single tapentadol doses resulted in tapentadol serum concentrations within the targeted range known to be safe and efficacious in adults and compared well to the range observed for children aged 2 to <18 years. Pain intensity already improved 15 min after administration. In the multiple dose trial, amounts of supplemental opioid analgesic medication within the first 24 h after start of trial medication were low (placebo 0.02 mg/kg, tapentadol 0.05 mg/kg). All patients stopped treatment with the trial medication because opioid analgesics were no longer required. Treatment-emergent adverse events occurred in 42.1% (tapentadol OS single dose), 28.9% (tapentadol IV), and 75% of placebo and 54.5% of tapentadol patients (tapentadol OS multiple doses), none of them serious. CONCLUSION: Tapentadol showed a favorable PK and safety profile in children <2 years of age. Multiple tapentadol OS dosing is efficacious and generally well tolerated in children ≥2 years and might also be a useful treatment option for children <2 years in need of strong analgesics.

Localised neuropathic pain in the primary care setting: a cross-sectional study of prevalence, clinical characteristics, treatment patterns, quality of life and sleep performance.

BACKGROUND: Localised Neuropathic Pain (LNP) is challenging to diagnose and manage in primary care. OBJECTIVE: To describe clinical characteristics, treatment patterns, quality of life and sleep performance of patients with LNP and estimate its prevalence in primary care. METHODS: Cross-sectional study in 4 European countries. Patients were identified using a screening tool for LNP. Patients completed the EQ-5D VAS score and Chronic Pain Sleep Inventory (CPSI). RESULTS: There were 1030 LNP patients for analysis. They presented a median pain intensity of 6.0 (IQR 4.0-7.0) with a median duration of 30.9 months (IQR 12.0-75.3), despite 97% receiving pain treatment. Main sites affected were the limbs (62% upper/58% lower) and spine (41%). Main aetiologies were neuropathic low back pain (47%), post-surgical neuropathic pain (17%), and diabetic poly-neuropathy (12%). Thirty percent received a single analgesic (2% topical), while combinations comprised 43% systemic-systemic, 24% topical-systemic, 1% topical-topical. Medications included NSAIDs (45%), anticonvulsants (38%), WHO step 2 opioids (35%), and topical analgesics (27%). In the previous 6 months, 40% had switched treatment. The mean (SD) EQ-5D VAS score was 58 (22.3) and the mean (SD) EQ-5D summary score (UK tariff) was 0.62 (0.25). Patients had a CPSI mean index of 41/100, and sleeping pills were used by 33% of patients. The standardized prevalence of LNP by age and sex was 2.01% in the general population and 43.3% among chronic pain patients. CONCLUSIONS: Many LNP patients reported pain intensities of six on a ten-point scale in average for durations longer than 2.5 years, with quality of life and sleep performance affected, with frequent treatment combinations and switches, suggesting suboptimal pain management.

Inclusion of a priori information in genome-wide association analysis.

Genome-wide association studies (GWAS) continue to gain in popularity. To utilize the wealth of data created more effectively, a variety of methods have recently been proposed to include a priori information (e.g., biologically interpretable sets of genes, candidate gene information, or gene expression) in GWAS analysis. Six contributions to Genetic Analysis Workshop 16 Group 11 applied novel or recently proposed methods to GWAS of rheumatoid arthritis and heart disease related phenotypes. The results of these analyses were a variety of novel candidate genes and sets of genes, in addition to the validation of well-known genotype-phenotype associations. However, because many methods are relatively new, they would benefit from further methodological research to ensure that they maintain type I error rates while increasing power to find additional associations. When methods have been adapted from other study types (e.g., gene expression data analysis or linkage analysis), the lessons learned there should be used to guide implementation of techniques. Lastly, many open research questions exist concerning the logistic details of the origin of the a priori information and the way to incorporate it. Overall, our group has demonstrated a strong potential for identifying novel genotype-phenotype relationships by including a priori data in the analysis of GWAS, while also uncovering a series of questions requiring further research.

Tapentadol Prolonged Release for Severe Chronic Osteoarthritis Pain in the Elderly-A Subgroup Analysis of Routine Clinical Practice Data.

Background: Tapentadol prolonged release (PR) has been shown effective and generally well tolerated in a broad range of chronic pain conditions. This subgroup analysis investigated its benefits for elderly patients with severe chronic osteoarthritis (OA) pain in routine clinical practice. Patients and Methods. Data of all patients with chronic OA pain were extracted from the database of a prospective, 3-month noninterventional tapentadol PR trial. The data of elderly OA patients (>65 years of age; n = 752) were compared with the data of younger OA patients (≤65 years; n = 282). Results: Almost all patients (elderly 98.7% and younger patients 99.3%) had received long-term analgesic medication prior to the start of tapentadol PR treatment but presented with severe pain accompanied by considerable impairments in sleep quality and quality of life measures. Tapentadol PR provided effective pain relief in both patient groups, with slightly better outcomes in younger patients. However, the mean baseline pain intensity of 7.1 (SD 1.5) was reduced by 3.8 points (p ≤ 0.001), and sleep and quality of life measures had also markedly improved in the elderly: quality of sleep by 3 points, quality of life by 3.4 points, social activities by 3 points, and independence by 2.7 points (p ≤ 0.001 for all measures; 11-point scale). At the end of observation, 68% of the elderly had clinically relevant pain reductions of at least 50% (vs baseline), and 87.9% attained either their intended pain reduction target and/or an additional individual treatment target (both predefined during baseline examination). Only 8.4% of the elderly experienced adverse drug reactions, most frequently nausea (2.7% of patients) and dizziness (1.5%). Conclusion: Tapentadol PR provided effective and well-tolerated treatment of severe chronic OA pain for elderly patients in routine clinical practice. The favorable tolerability profile in particular suggests tapentadol PR as a treatment option before classical strong opioids are considered.

Tapentadol prolonged release for severe chronic osteoarthritis pain in the elderly: improvements in daily functioning and quality of life.

Background: Chronic osteoarthritis (OA) pain leads to severe impairments in physical functioning and quality of life. Patients & methods: Data of patients with severe chronic knee and/or hip OA pain were extracted from the database of a prospective, noninterventional trial to assess the benefits of tapentadol prolonged release (PR) in elderly patients (>65 years of age; n = 1162) compared with younger patients (≤65 years of age; n = 498). Results: Tapentadol PR treatment (up to 3 months) significantly reduced pain intensity and pain-related restrictions on daily functioning and significantly improved physical and mental quality of life in both patient groups. The incidence of adverse drug reactions was low. Conclusion: Tapentadol PR is a useful strong analgesic to improve pain intensity, physical functioning and quality of life in elderly OA patients.

Tapentadol Prolonged Release for Long-Term Treatment of Pain in Children.

PURPOSE: Investigation of the efficacy and safety of tapentadol prolonged release (PR) compared with morphine PR for long-term treatment of pain in children. PATIENTS AND METHODS: Children aged 6 to <18 years requiring long-term treatment with opioids were studied in a 12-month, 2-part, multi-center trial: Part 1, 14-day open-label, randomized, active-controlled, parallel group non-inferiority trial comparing twice daily tapentadol PR with morphine PR; Part 2, open-label treatment with tapentadol PR for up to 12 months or no treatment "safety observation period". Pain intensity was rated with visual analogue scale or Faces Pain Scale-Revised, and non-inferiority was assessed by comparison of "treatment responders" (those completing the 14-day treatment period and showing pre-defined changes in pain rating) in each group. RESULTS: Twenty-three of 48 centers enrolled 73 patients. In Part 1, 45 and 24 patients received tapentadol or morphine, respectively, of which 40 and 22 completed 14-day treatment. In Part 2, thirty-six and 58 patients entered the tapentadol PR or observation periods, respectively, with 20/36 completing at least 12 weeks of treatment; 10 of the 36 had received morphine in Part 1. Forty-four of the 58 patients in the safety observation period had received tapentadol. Tapentadol PR was non-inferior to morphine PR (lower limit of confidence interval above negative non-inferiority margin of -0.2) in Part 1. Rates of adverse events were as expected with nausea (22.2%) and constipation (15.6%) in the tapentadol PR group, and with vomiting (33.3%), nausea and constipation (each 16.7%) in the morphine PR group. No new safety issues were identified; the safety profile of tapentadol over the 12 months treatment and observation periods was comparable to that established in subjects >18 years old. CONCLUSION: Tapentadol PR was well tolerated and equivalent to morphine PR for both efficacy and safety in children (6 to <18 years old) requiring long-term treatment with opioids.

Tapentadol immediate release for moderate to severe acute post-surgery pain.

OBJECTIVE: To investigate efficacy and tolerability of tapentadol immediate release (IR) in the treatment of moderate to severe acute pain in three surgical pain models. DESIGN: Three randomized, double-blind, placebo- and active-controlled, multicenter, phase 3 trials were performed in total hip replacement surgery, abdominal hysterectomy, and bunionectomy with trial medications administered every 4-6 hours as needed for up to 72 hours. Tapentadol IR was included in all trials, oxycodone IR in the total hip replacement trial, and morphine IR in the abdominal hysterectomy and bunionectomy trials; active controls ensured assay sensitivity. MAIN OUTCOME MEASURES: The primary efficacy endpoint was the sum of pain intensity differences over the first 24 hours of treatment (SPID24) in the abdominal hysterectomy trial and SPID48 in the other two trials. Tolerability was assessed by adverse events reporting. RESULTS: A total of 330, 832, and 285 patients with total hip replacement, abdominal hysterectomy, and bunionectomy, respectively, were assessed for efficacy. All three trials demonstrated statistically significant improvements of tapentadol IR on the primary endpoint versus placebo and similar improvements compared to morphine IR or oxycodone IR. These findings were consistent with results of total pain relief assessments and patients' global impressions of change in their overall health status after 72 hours (abdominal hysterectomy, bunionectomy). The tolerability profile of tapentadol IR was as expected for a centrally acting analgesic in the post-surgery setting. CONCLUSIONS: Tapentadol IR has strong analgesic efficacy and is well tolerated in multiple post-surgery conditions of moderate to severe pain.

Pharmacokinetics, safety, and efficacy of tapentadol oral solution for treating moderate to severe pain in pediatric patients.

Background: This trial is part of the global pediatric clinical development program investigating the administration of the strong analgesic tapentadol in children and adolescents. Patients and methods: The single site, open-label phase 2 trial evaluated the pharmacokinetic profile of tapentadol and its major metabolite, tapentadol-O-glucuronide, as well as safety and tolerability and efficacy of a single dose of tapentadol oral solution (1 mg/kg) in patients (2 to <18 years) undergoing dental, ear, nose, or throat surgery. Blood sampling and pain intensity measurements were conducted using age-appropriate schedules and rating scales, respectively. Adverse events were monitored throughout the trial. Results: Sixty-six patients were treated. They were stratified by age: Group 1 (12 to <18 years), n=21; Group 2 (6 to <12 years), n=28; and Groups 3 (3 to <6 years) and 4 (2 to <3 years), n=17. Serum tapentadol concentrations observed in these pediatric patients were within the range observed in adults after administration of a single tapentadol immediate-release dose (50-100 mg), whereas those of the metabolite tapentadol-O-glucuronide were within the same range or lower than in adults who received comparable single doses of tapentadol. Pain intensity improved over time across all age groups. The most common treatment-emergent adverse events were nausea (24.2%), vomiting (16.7%), dizziness (9.1%), and headache (6.1%). Conclusion: A single dose of tapentadol oral solution (1 mg/kg) administered to pediatric patients (2 to <18 years) resulted in serum tapentadol concentrations within the targeted range shown to be safe and efficacious in adults. Tapentadol demonstrated good tolerability and safety; within the limitations of the trial design, improvements in postsurgical pain intensity were observed across the age groups. Tapentadol may provide a new treatment option in the management of moderate to severe pediatric pain.

Efficacy and safety of tapentadol prolonged release formulation in the treatment of elderly patients with moderate-to-severe chronic osteoarthritis knee pain: a pooled analysis of two double-blind, randomized, placebo-, and active-controlled trials.

OBJECTIVE: To compare efficacy and safety of tapentadol prolonged release (PR) vs oxycodone controlled release (CR) in younger patients (<65 years of age) and in elderly patients (≥65 and ≥75 years of age) in the treatment of moderate-to-severe chronic osteoarthritis (OA) knee pain. METHODS: Data from two double-blind, randomized, placebo-, and oxycodone CR-controlled phase 3 trials were pooled and stratified by age. Primary efficacy end-points were change from baseline in average pain intensity at week 12 (US end-point) and over the entire maintenance period (non-US end-point). RESULTS: A total of 1357 patients <65 years, 653 patients ≥65 years, and 176 patients ≥75 years of age were assessed. The comparison between tapentadol PR and oxycodone CR showed numerically better pain relief under tapentadol PR for both primary end-points in all three age groups. More favorable improvements were also observed for patient global impression of change, the Short Form-36 physical component score, and EuroQoL-5Dimensions health status index. In the elderly, incidences of dizziness and somnolence were comparable between active treatments, but incidences of nausea, vomiting, and constipation were considerably lower under tapentadol PR. Treatment completion rates were lowest under oxycodone CR; > 50% of elderly oxycodone CR patients named side-effects as the main reason for discontinuation. CONCLUSIONS: Tapentadol PR was effective in the treatment of moderate-to-severe chronic OA pain in elderly and younger patients. Compared to oxycodone CR, the overall and the gastrointestinal tolerability profile in particular were better in all tapentadol PR groups, regardless of age.

Review of Post-Marketing Safety Data on Tapentadol, a Centrally Acting Analgesic.

INTRODUCTION: Tapentadol is a centrally acting analgesic that has been available for the management of acute and chronic pain in routine clinical practice since 2009. METHODS: This is the first integrated descriptive analysis of post-marketing safety data following the use of tapentadol in a broad range of pain conditions relating to the topics overall safety, dose administration above approved dosages, administration during pregnancy, serotonin syndrome, respiratory depression, and convulsion. The data analyzed pertain to spontaneous reports from healthcare and non-healthcare professionals and were put in the context of safety information known from interventional and non-interventional trials. RESULTS: The first years of routine clinical practice experience with tapentadol have confirmed the tolerability profile that emerged from the clinical trials. Moreover, the reporting of expected side effects such as respiratory depression and convulsion was low and no major risks were identified. The evaluation of available post-marketing data did not confirm the theoretical risk of serotonin syndrome nor did it reveal unexpected side effects with administration of higher than recommended doses. CONCLUSION: More than 8 years after its first introduction, the favorable overall safety profile of tapentadol in the treatment of various pain conditions is maintained in the general population. FUNDING: Grünenthal GmbH.

Gene-set meta-analysis of lung cancer identifies pathway related to systemic lupus erythematosus.

INTRODUCTION: Gene-set analysis (GSA) is an approach using the results of single-marker genome-wide association studies when investigating pathways as a whole with respect to the genetic basis of a disease. METHODS: We performed a meta-analysis of seven GSAs for lung cancer, applying the method META-GSA. Overall, the information taken from 11,365 cases and 22,505 controls from within the TRICL/ILCCO consortia was used to investigate a total of 234 pathways from the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. RESULTS: META-GSA reveals the systemic lupus erythematosus KEGG pathway hsa05322, driven by the gene region 6p21-22, as also implicated in lung cancer (p = 0.0306). This gene region is known to be associated with squamous cell lung carcinoma. The most important genes driving the significance of this pathway belong to the genomic areas HIST1-H4L, -1BN, -2BN, -H2AK, -H4K and C2/C4A/C4B. Within these areas, the markers most significantly associated with LC are rs13194781 (located within HIST12BN) and rs1270942 (located between C2 and C4A). CONCLUSIONS: We have discovered a pathway currently marked as specific to systemic lupus erythematosus as being significantly implicated in lung cancer. The gene region 6p21-22 in this pathway appears to be more extensively associated with lung cancer than previously assumed. Given wide-stretched linkage disequilibrium to the area APOM/BAG6/MSH5, there is currently simply not enough information or evidence to conclude whether the potential pleiotropy of lung cancer and systemic lupus erythematosus is spurious, biological, or mediated. Further research into this pathway and gene region will be necessary.

Integration of a priori gene set information into genome-wide association studies.

In genome-wide association studies (GWAS) genetic markers are often ranked to select genes for further pursuit. Especially for moderately associated and interrelated genes, information on genes and pathways may improve the selection. We applied and combined two main approaches for data integration to a GWAS for rheumatoid arthritis, gene set enrichment analysis (GSEA) and hierarchical Bayes prioritization (HBP). Many associated genes are located in the HLA region on 6p21. However, the ranking lists of genes and gene sets differ considerably depending on the chosen approach: HBP changes the ranking only slightly and primarily contains HLA genes in the top 100 gene lists. GSEA includes also many non-HLA genes.

Case-control studies with affected sibships.

Related cases may be included in case-control association studies if correlations between related individuals due to identity-by-descent (IBD) sharing are taken into account. We derived a framework to test for association in a case-control design including affected sibships and unrelated controls. First, a corrected variance for the allele frequency difference between cases and controls was directly calculated or estimated in two ways on the basis of the fixation index FST and the inbreeding coefficient. Then the correlation-corrected association test including controls and affected sibs was carried out. We applied the three strategies to 20 candidate genes on the Genetic Analysis Workshop 15 rheumatoid arthritis data and to 9187 single-nucleotide polymorphisms of replicate one of the Genetic Analysis Workshop 15 simulated data with knowledge of the "answers". The three strategies used to correct for correlation give only minor differences in the variance estimates and yield an almost correct type I error rate for the association tests. Thus, all strategies considered to correct the variance performed quite well.