Estimating heterogeneity of treatment effect in psychiatric clinical trials.

Currently, placebo-controlled clinical trials report mean change and effect sizes, which masks information about heterogeneity of treatment effects (HTE). Here, we present a method to estimate HTE and evaluate the null hypothesis (H0) that a drug has equal benefit for all participants (HTE=0). We developed measure termed 'estimated heterogeneity of treatment effect' or eHTE, which estimates variability in drug response by comparing distributions between study arms. This approach was tested across numerous large placebo-controlled clinical trials. In contrast with variance-based methods which have not identified heterogeneity in psychiatric trials, reproducible instances of treatment heterogeneity were found. For example, heterogeneous response was found in a trial of venlafaxine for depression (peHTE=0.034), and two trials of dasotraline for binge eating disorder (Phase 2, peHTE=0.002; Phase 3, 4mg peHTE=0.011; Phase 3, 6mg peHTE=0.003). Significant response heterogeneity was detected in other datasets as well, often despite no difference in variance between placebo and drug arms. The implications of eHTE as a clinical trial outcomes independent from central tendency of the group is considered and the important of the eHTE method and results for drug developers, providers, and patients is discussed.

Application of hypothetical strategies in acute pain.

Since the publication of ICH E9 (R1), "Addendum to statistical principles for clinical trials: on choosing appropriate estimands and defining sensitivity analyses in clinical trials," there has been a lot of debate about the hypothetical strategy for handling intercurrent events. Arguments against the hypothetical strategy are twofold: (1) the clinical question has limited clinical/regulatory interest; (2) the estimation may need strong statistical assumptions. In this article, we provide an example of a hypothetical strategy handling use of rescue medications in the acute pain setting. We argue that the treatment effect of a drug that is attributable to the treatment alone is the clinical question of interest and is important to regulators. The hypothetical strategy is important when developing non-opioid treatment as it estimates the treatment effect due to treatment during the pre-specified evaluation period whereas the treatment policy strategy does not. Two widely acceptable and non-controversial clinical inputs are required to construct a reasonable estimator. More importantly, this estimator does not rely on additional strong statistical assumptions and is considered reasonable for regulatory decision making. In this article, we point out examples where estimators for a hypothetical strategy can be constructed without any strong additional statistical assumptions besides acceptable clinical inputs. We also showcase a new way to obtain estimation based on disease specific clinical knowledge instead of strong statistical assumptions. In the example presented, we clearly demonstrate the advantages of the hypothetical strategy compared to alternative strategies including the treatment policy strategy and a composite variable strategy.

Identification of renal cyst cells of type I Nephronophthisis by single-nucleus RNA sequencing.

Background: Nephronophthisis (NPH) is the most common genetic cause of end-stage renal disease (ESRD) in childhood, and NPHP1 is the major pathogenic gene. Cyst formation at the corticomedullary junction is a pathological feature of NPH, but the mechanism underlying cystogenesis is not well understood. The isolation and identification of cystic cell subpopulation could help to identify their origins and provide vital clues to the mechanisms underlying cystogenesis in NPH. Methods: Single-nucleus RNA sequencing (snRNA-seq) was performed to produce an atlas of NPHP1 renal cells. Kidney samples were collected from WT (Nphp1 +/+) mice and NPHP1 (Nphp1 del2-20/del2-20) model mice. Results: A comprehensive atlas of the renal cellular landscape in NPHP1 was generated, consisting of 14 basic renal cell types as well as a subpopulation of DCT cells that was overrepresented in NPHP1 kidneys compared to WT kidneys. GO analysis revealed significant downregulation of genes associated with tubular development and kidney morphogenesis in this subpopulation. Furthermore, the reconstruction of differentiation trajectories of individual cells within this subpopulation confirmed that a specific group of cells in NPHP1 mice become arrested at an early stage of differentiation and proliferate to form cysts. We demonstrate that Niban1 is a specific molecular marker of cystic cells in both mice and human NPHP1. Conclusion: In summary, we report a novel subpopulation of DCT cells, marked by Niban1, that are classified as cystic cells in the NPHP1 mice kidney. These results offer fresh insights into the cellular and molecular basis of cystogenesis in NPH.

SIRIUS, Ultra-Scintillating Upconversion Breast Implant for Remote Orthotopic Photodynamic Therapy.

Present day strategies for delivery of wireless photodynamic therapy (PDT) to deep-seated targets are limited by the inadequacy of irradiance and insufficient therapeutic depth. Here we report the design and preclinical validation of a flexible wireless upconversion nanoparticle (UCNP) implant (SIRIUS) that is capable of large field, high intensity illumination for PDT of deep-seated tumors. The implant achieves this by incorporating submicrometer core-shell-shell NaYF4 UCNPs into its design, which significantly enhances upconversion efficiency and mitigates light loss from surface quenching. We demonstrate the efficacy of SIRIUS UCNP implant mediated PDT in preclinical breast cancer disease models. In our in vitro experiments, SIRIUS directed 5-Aminolevulinic Acid (5-ALA) based wireless PDT leads to significant reactive oxygen species (ROS) generation and tumor apoptosis in hormonal receptor+/HER2+ (MCF7) and triple-negative (MDA-MB-231) breast cancer cell lines. In our in vivo rodent model, SIRIUS-driven PDT is shown to be significant in regressing tumors when applied to orthotopically inoculated breast tumors. Following successful preclinical validation, we also describe a clinical prototype of UCNP breast implant with potential dual cosmetic and onco-therapeutic functions. SIRIUS is an upconversion breast implant for wireless PDT that fulfils all the design prerequisites necessary for seamless clinical translation.

Efficacy and safety of Sanfeng Tongqiao Diwan in patients with allergic rhinitis: a single-arm clinical trial in China.

Background: Traditional Chinese medicine (TCM) has a long history and its own characteristics in the treatment of allergic rhinitis. In this study, the efficacy and safety of patients with allergic rhinitis treated with Sanfeng Tongqiao Diwan were observed to support the clinical medication of patients with allergic rhinitis. Methods: A total of 61 patients with allergic rhinitis aged 12-70 years from the First Affiliated Hospital of Guangzhou Medical University were included in this study. All the patients were treated with Sanfeng Tongqiao Diwan for a period of 7 days. Return visits were carried out 24 hours after the first medication, the 4th day of medication, and the 7th day of medication, during which the efficacy and safety were assessed. Results: The effective rates of Sanfeng Tongqiao Diwan at 24 hours, 4 days, and 7 days were 49.2%, 60.7%, and 65.6%, respectively. Comparing the severity of various symptoms after treatment to baseline, significant differences were found in nasal secretion (2.95±0.67 vs. 2.26±1.30, P<0.001), stuffy nose (5.66±2.95 vs. 3.34±2.57, P<0.001), mucosa congestion (7.08±1.82 vs. 4.23±2.28, P<0.001), running nose (5.21±1.81 vs. 2.90±1.89, P<0.001), and sneezing (3.00±0 vs. 1.92±1.45, P<0.001). The full symptom scores showed progressive decline during treatment, measuring 20.21±5.13 at baseline and 12.02±6.47 at 7 days (P<0.001). Compared to the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) score of 64.61±30.27 at baseline, statistical significance (P<0.001) was found at 24 hours, 4 days, and 7 days, measuring 43.11±28.01, 40.74±28.6, and 39.97±40.48, respectively. The incidence rate of adverse events (AEs) was 3.3% (2/61), with no serious AEs. Conclusions: In this study, the use of Sanfeng Tongqiao Diwan is effective in the treatment of allergic rhinitis patients, especially in patients with severe symptoms. Although the treatment system of TCM is different from that of Western medicine, the application of TCM will provide a new direction for the treatment of chronic diseases. Follow-up studies with an increased sample size are required for verification.

Rural Post-Earthquake Resettlement Mode Choices: Empirical Case Studies of Sichuan, China.

Earthquakes occur frequently in rural areas of Sichuan, China, causing huge damage and high mortality. The built environment plays a significant role in providing residents with safe and resilient settlements in such areas. There is yet little research on how rural families in developing countries cope with geological disasters like earthquakes, and how built environmental factors would influence their resettlement choices which would directly affect their quality of life afterward. Urban planning activities should be accompanied by these insights to design and create human-centric resettlements accordingly. In this study, the resettlement choices after three major earthquakes in Sichuan were studied for this reason. Random sampling and face-to-face questionnaire surveys were combined with factor analysis and binary logistic regression to understand the resettlement modes desired by the residents and the influencing factors. The results show that residents who have lived in their current places long and whose houses were not built recently are more likely to choose the in-situ resettlement. Accessibility to employment and public services has a significant impact on residents' choice of in-situ resettlement or reallocated resettlement, and so does the previous resettlement experience. The research results can provide useful suggestions for Chinese rural area post-earthquake resettlement planning following a human-centric approach with empirical data.

[Analysis of SALL1 gene variant in a boy with Townes-Brocks syndrome without anal atresia].

OBJECTIVE: To explore the genetic basis for a child presented with renal failure and multi-cystic dysplastic kidney without anal atresia. METHODS: Peripheral blood sample of the child and his parents were collected and subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: The 40-day-old infant had presented with vomiting brown matter in a 7 days neonate and was transferred for kidney failure. Clinical examination has discovered renal failure, polycystic renal dysplasia, congenital hypothyroidism, bilateral thumb polydactyly, sensorineural hearing loss and preauricular dermatophyte. Genetic testing revealed that he has harbored a previously unreported c.824delT, p.L275Yfs*10 frameshift variant of SALL1 gene, which was confirmed by Sanger sequencing as de novo. CONCLUSION: The patient was diagnosed with Townes-Brocks syndrome due to the novel de novo variant of SALL1 gene. Townes-Brocks syndrome without anal atresia is rare. Above finding has also enriched the mutational spectrum of the SALL1 gene.

Baricitinib in patients with moderate-to-severe atopic dermatitis: Results from a randomized monotherapy phase 3 trial in the United States and Canada (BREEZE-AD5).

BACKGROUND: Baricitinib, an oral selective Janus kinase 1/Janus kinase 2 inhibitor, is being studied for moderate-to-severe atopic dermatitis (AD) in adults. OBJECTIVE: To evaluate the efficacy and safety of baricitinib monotherapy in a North American phase 3 trial (BREEZE-AD5/NCT03435081) of adults with moderate-to-severe AD who responded inadequately or were intolerant to topical therapy. METHODS: Patients (N = 440) were randomized 1:1:1 to once-daily placebo or baricitinib (1 mg or 2 mg). The primary endpoint was the proportion of patients achieving ≥75% reduction in the Eczema Area and Severity Index at week 16. A key secondary endpoint was the proportion of patients achieving a validated Investigator Global Assessment for AD score of 0 (clear)/1(almost clear) with ≥2-point improvement. RESULTS: At week 16, the proportion of patients achieving Eczema Area and Severity Index was 8%, 13%, and 30% (P < .001, 2 mg vs placebo) and those with a validated Investigator Global Assessment for AD score of 0/1 were 5%, 13%, and 24% (P < .001, 2 mg vs placebo) for placebo, baricitinib 1 mg, and baricitinib 2 mg, respectively. Safety findings were similar to those of other baricitinib AD studies. LIMITATIONS: Short-term clinical trial results may not be generalizable to real-world settings. CONCLUSION: Baricitinib was efficacious for patients with moderate-to-severe AD with no new safety findings over 16 weeks.

Safety of baricitinib in East Asian patients with moderate-to-severe active rheumatoid arthritis: An integrated analysis from clinical trials.

AIM: We evaluated the safety of baricitinib in an East Asian (EA) patient population with moderate-to-severely active rheumatoid arthritis (RA), through an integrated sub-analysis of data from the overall baricitinib RA clinical program. METHODS: Data from EA patients who received any dose of baricitinib from five completed studies (1 Phase 2, 4 Phase 3) and an ongoing long-term extension study were pooled up to 1 September, 2016. Exposure-adjusted incidence rates (EAIR) and incidence rates (IRs), both per 100 patient-years (PY), were calculated. RESULTS: This analysis included 740 EA patients with 1294 PY of total baricitinib exposure (maximum 3.5 years). Overall, 109 patients discontinued baricitinib due to adverse events (AEs); EAIR: 8.4. No deaths were reported in this cohort. Serious AEs were reported by 125 patients (EAIR: 9.7). Serious infections were the most common serious AEs (n = 53, IR: 4.15). IR of herpes zoster infection was 6.2; the majority of events were of mild-to-moderate severity. Three cases (IR: 0.23) of tuberculosis were reported. The IRs of malignancy (excluding non-melanoma skin cancer) was 0.99 and EAIR specifically of lymphoma was 0.1. The IR of major adverse cardiovascular events was 0.26, and deep vein thrombosis was reported in four patients (EAIR: 0.3). Two cases of gastrointestinal perforations (EAIR: 0.2) were reported. CONCLUSION: Integrated data show that baricitinib is well-tolerated in EA patients with moderate-to-severely active RA in the context of demonstrated efficacy, which is generally consistent with safety results of the overall study population.

Safety profile of baricitinib for the treatment of rheumatoid arthritis over a median of 3 years of treatment: an updated integrated safety analysis.

BACKGROUND: Baricitinib is an oral selective inhibitor of Janus kinase (JAK) 1 and JAK2, approved for the treatment of patients with active rheumatoid arthritis. Because baricitinib, like other disease-modifying antirheumatic drugs, is used chronically, continuous assessment of its long-term safety profile is important. Here we provide updated data supporting the existing safety profile of baricitinib in this patient population. METHODS: In this safety analysis, integrated data were included from nine phase 3, phase 2, and phase 1b clinical trials, and one long-term extension study with data up to 360 weeks, ending Feb 13, 2018. We analysed three integrated datasets, the largest of which was the all-bari-RA dataset, which includes patients who received any dose of baricitinib. We compared the safety of baricitinib with placebo on the basis of data from seven studies with baricitinib 4 mg and placebo and four studies with baricitinib 2 mg, including placebo to week 24 (placebo-controlled dataset). We did a dose-response assessment based on four studies with baricitinib 2 mg and 4 mg, including long-term extension data (2-4 mg extended dataset). We did an exploratory analysis of deaths and venous thromboembolic events in a subset of data from the all-bari-RA dataset that included patients who had ever taken baricitinib 2-mg or baricitinib 4-mg. We did an analysis for malignancies (excluding non-melanoma skin cancer) in the as-randomised population (patients not censored at rescue or dose change). FINDINGS: We collected data for 3770 patients who were given baricitinib for 10 127 patient-years of exposure in the all-bari-RA dataset (median 1115 days [IQR 426-1441], maximum 2520 days). The placebo-controlled dataset comprised 2836 patients, with 1215 in the placebo group, with 451 patient-years of exposure data; 479 in the baricitinib 2 mg group, with 186 patient-years of exposure data; and 1142 in the baricitinib 4 mg group, with 472 patient-years of exposure data. The 2-4 mg extended dataset comprised 958 patients, with 479 in both the 2 mg and 4 mg groups. No significant differences were seen for baricitinib 4 mg or 2 mg versus placebo, or for 4 mg versus 2 mg in the incidence of death, malignancy, serious infection, or major adverse cardiovascular events. Incidence of herpes zoster per 100 patient-years was higher for baricitinib (4 mg: 4·4 [95% CI 2·7-6·7]; 2 mg: 3·1 [1·1-6·8]) versus total placebo group (1·1 [0·4-2·5]), as were treatment-emergent infections (4 mg: 89·7 [81·3-98·6]; 2 mg: 84·0 [71·3-98·2] vs placebo 75·4 [67·6-83·9]). Consistent with previous reports, incidences in the all-bari-RA dataset for venous thromboembolic events was 0·5 (95% CI 0·4-0·6) per 100 patient-years, deep-vein thrombosis was 0·3 (0·2-0·5) per 100 patient-years, and pulmonary embolism was 0·2 (0·2-0·4) per 100 patient-years. Incidences of malignancy (excluding non-melanoma skin cancer) in the 2-4 mg extended dataset were 0·8 (0·4-1·5) per 100 patient-years for baricitinib 2 mg and 1·0 (0·5-1·7) per 100 patient-years for baricitinib 4 mg, without censoring patients who had dose changes or received rescue treatment. We found no indication of higher incidence of venous thromboembolic events in the baricitinib 4 mg group compared with the 2 mg group in the 2-4 mg extended dataset. INTERPRETATION: In this updated integrated analysis of patients with active rheumatoid arthritis exposed to baricitinib for a maximum of almost 7 years, baricitinib 2 mg and 4 mg maintained a similar safety profile to earlier analyses. No new safety signals were identified. Patients in the long-term extension study continue to be followed up to date. FUNDING: Eli Lilly and Company, under license from Incyte Corporation.

Safety and Efficacy of Baricitinib in Patients Receiving Conventional Synthetic Disease-Modifying Antirheumatic Drugs or Corticosteroids.

INTRODUCTION: This study assessed if concomitant use of conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) or corticosteroids altered the response or safety outcomes to baricitinib in rheumatoid arthritis (RA) patients. METHODS: Patients with ≥ 6 swollen/tender joints and no prior biologic DMARD were eligible for study inclusion. In RA-BUILD, csDMARD-inadequate responder (IR) patients were randomized to placebo or baricitinib (2 or 4 mg) once daily (QD). In RA-BEAM, methotrexate (MTX)-IR patients were randomized to placebo QD, baricitinib 4-mg QD, or adalimumab 40-mg biweekly. Patients continued background csDMARD (including MTX) therapy. This post hoc analysis of placebo and baricitinib 4-mg patients assessed the number and type of concomitant csDMARDS and concurrent corticosteroid use. RESULTS: From 716 placebo patients, 71, 21, and 6% were taking MTX alone, MTX + ≥ 1 csDMARD, and non-MTX csDMARDs, respectively; from 714 baricitinib patients, the rates were 74, 18, and 6%; 56% of placebo and 55% of baricitinib patients used corticosteroids at baseline (mean dose, 6.0 mg/day for both groups); patients continued use throughout the studies. The odds ratios for achieving American College of Rheumatology response at the 20% improvement level (ACR20) and Clinical Disease Activity Index (CDAI) ≤ 10 at week 12 favored baricitinib for most subgroups; no significant interactions were observed. Rates of adverse events were similar regardless of csDMARD group or corticosteroid use. There were numerically more serious adverse events in placebo patients taking corticosteroids (4.2 vs. 1.6%) and a higher rate of discontinuations in baricitinib patients taking corticosteroids (4.1 vs. 1.2%). CONCLUSIONS: Baricitinib was efficacious regardless of concomitant use of csDMARDs or corticosteroids; the incidence of adverse events was similar across all groups of patients. FUNDING: Eli Lilly and Company and Incyte Corporation.

Response to baricitinib therapy in patients with rheumatoid arthritis with inadequate response to csDMARDs as a function of baseline characteristics.

OBJECTIVE: We analysed the effects of baseline characteristics on the safety and efficacy of baricitinib in patients with rheumatoid arthritis (RA) with inadequate response to conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) from two phase III trials. METHODS: In RA-BEAM (NCT01710358), patients with inadequate response to methotrexate were randomised to placebo, baricitinib 4 mg or adalimumab 40 mg. RA-BUILD (NCT01721057) patients had inadequate response to ≥1 csDMARDs and were randomised to either placebo or once-daily baricitinib (2 or 4 mg). Both study populations were naïve to biologic DMARDs (bDMARDs). Primary end point for both studies was American College of Rheumatology 20% improvement (ACR20) response at week 12. Pooled data from the two trials were analysed post hoc based on select subgroups defined by age, previous csDMARD use, baseline RA disease activity, etc, with assessment of clinical and safety outcomes at week 12 and radiographic outcomes at week 24 for the baricitinib 4 mg and placebo-treated patients. RESULTS: Efficacy was observed with baricitinib 4 mg treatment irrespective of patient demographics and baseline disease characteristics. ORs primarily favoured baricitinib over placebo in the ACR20 response. In other outcomes such as Disease Activity Score for 28 joints based on high-sensitivity C reactive protein levels, Simplified Disease Activity Index score ≤11 and radiographic progression, baricitinib 4 mg showed better responses than placebo regardless of baseline characteristics. Safety events were more common in patients over 65 years, but similar between baricitinib 4 mg and placebo patients. CONCLUSION: Baseline characteristics did not substantially affect clinical response to baricitinib 4 mg in patients with RA with inadequate response to csDMARDs.

Lipid profile and effect of statin treatment in pooled phase II and phase III baricitinib studies.

OBJECTIVES: Lipid profiles are altered by active disease in patients with rheumatoid arthritis (RA) and may be further modified by treatment with Janus kinase inhibitors and other disease-modifying antirheumatic drugs. METHODS: Lipid data were analysed from phase II and III studies of 4 mg (n=997) and 2 mg (n=479) oral baricitinib administered once daily in patients with moderate-to-severe active RA. Lipoprotein particle size and number and GlycA were evaluated with nuclear magnetic resonance in one phase III study. The effect of statin therapy on lipid levels was evaluated in patients on statins at baseline and in patients who initiated statins during the study. RESULTS: Treatment with baricitinib was associated with increased levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides, but no significant change in LDL-C:HDL-C ratio. Lipid levels plateaued after 12 weeks of treatment. Baricitinib treatment increased large LDL and decreased small, dense LDL particle numbers and GlycA. Lipid changes from baseline were not significantly different between baseline statin users and non-users. In patients who initiated statin therapy during the study, LDL-C, triglycerides (baricitinib 4 mg only) and apolipoprotein B decreased to pre-baricitinib levels; HDL-C and apolipoprotein A-I levels remained elevated. CONCLUSIONS: Baricitinib was associated with increased LDL-C, HDL-C and triglyceride levels, but did not alter the LDL-C:HDL-C ratio. Evaluation of cardiovascular event rates during long-term treatment is warranted to further characterise these findings and their possible clinical implications. TRIAL REGISTRATION NUMBER: NCT00902486, NCT01469013, NCT01185353, NCT01721044, NCT01721057, NCT01711359, NCT01710358, NCT01885078.

Design considerations for handling dropouts in anti-depressant drug trials.

BACKGROUND: In clinical trials, statistical analysis often requires certain assumptions about missing data for a valid statistical inference. If the dropout rate is high, a wrong assumption about the missing data may compromise the validity of statistical inferences. PURPOSE: To mitigate the high dropout rates commonly observed in psychiatry clinical trials, we consider two design approaches for short-term controlled trials submitted in support of marketing applications for drug products for the major depressive disorder (MDD) indication: (1) shortening the trial duration and (2) treating time to treatment discontinuation as an alternative primary efficacy endpoint. METHODS: Subject-level efficacy data from 45 trials for drugs approved for an MDD indication between 1997 and 2014 were collected. We analyzed change from baseline in Hamilton Depression Rating Scale (HAMD-17) total score using the mixed model repeated measures approach. We compared the least squares means and the 95% confidence intervals of the treatment effect among three different trial durations, 4, 6, and 8weeks. We considered two definitions of discontinuation: (i) all-cause discontinuation, (ii) discontinuation due to lack of efficacy. We compared the two-sided log-rank p-values with the p-values from the protocol-specified primary analysis. CONCLUSIONS: Our findings suggest that MDD trials in the acute setting may be shortened to 6weeks provided that the treatment difference between drug and placebo on HAMD-17 total score reaches approximately 2units at Week 6. However, our exploratory analyses of available data do not support the use of time to treatment discontinuation as an alternative primary efficacy endpoint.

Using tolerance intervals for assessment of pharmaceutical quality.

In quality control of drug products, tolerance intervals are commonly used methods to assure a certain proportion of the products covered within a pre-specified acceptance interval. Depending on the nature of the quality attributes, the corresponding acceptance interval could be one-sided or two-sided. Thus, the tolerance intervals can also be one-sided or two-sided. To better utilize tolerance intervals for quality assurance, we reviewed the computation method and studied their statistical properties in terms of batch acceptance probability in this article. We also illustrate the application of one-sided and two-sided tolerance, as well as two one-sided tests through the examples of dose content uniformity test, delivered dose uniformity test, and dissolution test.

Multiple comparisons of repeated measured response: issues of assessment of prolongation of QT interval in thorough QT trials.

The primary objective of a thorough QT clinical trial is to demonstrate the lack of QT prolongation induced by the test treatment. The ICH E14 guidance defined drug-induced prolongation of QT interval as evidenced by an upper bound of the 95% one-sided confidence interval around the mean effect on QTc of 10 ms. Furthermore, it defined a negative thorough QT/QTc study as one in which the upper bound of the 95% one-sided confidence interval for the largest time-matched mean effect of the drug on the QTc interval excludes 10 ms. Conventionally, this objective is tested with the intersection-union test by testing the mean difference between the test treatment and placebo of QTc changes from baseline at each of the matched time points. The multiple-comparison nature of the test leads to higher false positive rate when comparisons are made repeatedly at multiple time points. Many approaches have been proposed in the last 5 years in order to improve the efficiency of the test. In this article, we survey and discuss some of the approaches.

Multiple comparisons of repeatedly measured response: issues of validation testing in thorough QT/QTc clinical trials.

In order to validate the results of a thorough QT/QTc clinical trial, ICH E14 recommended that a concurrent positive control treatment be included in the trial. Zhang (2008) recommended that the study results are validated if the positive control establishes assay sensitivity, i.e., has an effect on the mean QT/QTc interval of 5 ms or more. Zhang (2008) and Tsong et al. (2008) discussed the intersection-union test approach and an alternative global average test approach for testing assay sensitivity during the validation process. In this article, we further discuss the multiple comparison issues of the repeatedly measured QT difference between positive control treatment and placebo in the validation test. We describe and discuss several approaches for type I error rate adjustment that are applicable to the situation.

Statistical assessment of analytical method transfer.

Analytical method transfer is an important part of analytical method development and maintenance. The current common practice of analytical method transfer is based on the equivalence of the means between the original laboratory and the receiving laboratory. However, for some assays the most scientifically sound approach would be to show the equivalency of individual sample readings between the two laboratories. In this study, statistical approaches such as limit of agreement, total deviation index, and tolerance interval approach to address individual equivalence between laboratories are discussed. Using a tolerance interval approach that is equivalent to the two one-sided hypothesis testing is proposed. These approaches are compared with each other and also with the mean equivalence approach on their statistical properties. Examples are presented to illustrate each analysis approach and the comparisons.