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Methods to extend the strong internal validity of randomized controlled trials to reliably estimate treatment effects in target populations are gaining attention. This paper enumerates steps recommended for undertaking such extended inference, discusses currently viable choices for each one, and provides recommendations. We demonstrate a complete extended inference from a clinical trial studying a pharmaceutical treatment for Alzheimer's disease (AD) to a realistic target population of European residents diagnosed with AD. This case study highlights approaches to overcoming practical difficulties and demonstrates limitations of reliably extending inference from a trial to a real-world population. [ABSTRACT FROM AUTHOR]

Regulatory agencies typically evaluate the efficacy and safety of new interventions and grant commercial approval based on randomized controlled trials (RCTs). Other major healthcare stakeholders, such as insurance companies and health technology assessment agencies, while basing initial access and reimbursement decisions on RCT results, are also keenly interested in whether results observed in idealized trial settings will translate into comparable outcomes in real world settings—that is, into so‐called "real world" effectiveness. Unfortunately, evidence of real world effectiveness for new interventions is not available at the time of initial approval. To bridge this gap, statistical methods are available to extend the estimated treatment effect observed in a RCT to a target population. The generalization is done by weighting the subjects who participated in a RCT so that the weighted trial population resembles a target population. We evaluate a variety of alternative estimation and weight construction procedures using both simulations and a real world data example using two clinical trials of an investigational intervention for Alzheimer's disease. Our results suggest an optimal approach to estimation depends on the characteristics of source and target populations, including degree of selection bias and treatment effect heterogeneity. [ABSTRACT FROM AUTHOR]

Objective To report patient-reported outcomes of patients with PsA treated with ixekizumab up to 52 weeks. Methods In SPIRIT-P1, biologic-naïve patients with active PsA were randomized to ixekizumab 80 mg every 4 weeks (IXEQ4W; N = 107) or every 2 weeks (IXEQ2W; N = 103) following a 160 mg starting dose, adalimumab 40 mg every 2 weeks (ADA; N = 101) or placebo (PBO; N = 106) during the initial 24-week double-blind treatment period. At week 24 (week 16 for inadequate responders), ADA (8-week washout before starting ixekizumab) and PBO patients were re-randomized to IXEQ2W or IXEQ4W. Patients receiving ixekizumab at week 24 received the same dose during the extension period (EP) to week 52. Patients completed measures including the Dermatology Life Quality Index (DLQI), Itch Numeric Rating Scale, 36-Item Short Form Health Survey version 2, European Quality of Life 5 Dimensions Visual Analogue Scale and Work Productivity and Activity Impairment Questionnaire-Specific Health Problem. Results The IXEQ4W, IXEQ2W and ADA groups reported significant improvements in DLQI at week 24; 22% (PBO), 53% (IXEQ4W), 63% (IXEQ2W) and 54% (ADA) of patients reported DLQI scores of 0/1. The IXEQ4W, IXEQ2W and ADA groups reported significant improvements in Itch Numeric Rating Scale, 36-Item Short Form Health Survey version 2 physical component summary and some domain scores, and European Quality of Life 5 Dimensions Visual Analogue Scale at weeks 12 and 24; and in three of four Work Productivity and Activity Impairment Questionnaire-Specific Health Problem domains at week 24. Results are also presented through week 52 for the EP. Conclusion In biologic-naïve patients with active PsA, ixekizumab significantly improved skin symptoms, health-related quality of life and work productivity. Trial Registration ClinicalTrials.gov, http://clinicaltrials.gov, NCT01695239; EU Clinical Trials Register, https://www.clinicaltrialsregister.eu, EudraCT2011-002326-49 [ABSTRACT FROM AUTHOR]

Background: To assess the measurement properties of two single-item patient-reported outcome (PRO) measures that assessed the length of time (in minutes) and severity of morning joint stiffness (MJS) experienced each day.Methods: Data from two Phase 3, randomized placebo-controlled (and active-controlled [RA-BEAM]), clinical studies assessing the safety and efficacy of baricitinib in adults with moderately to severely active rheumatoid arthritis (RA) were used to evaluate the psychometric properties of the Duration of MJS and Severity of MJS PROs.Results: Test-retest reliability of Duration of MJS and Severity of MJS was supported through large intraclass correlation coefficients among stable patients (coefficient range for both studies: 0.88 to 0.93). In support of construct validity, moderate correlations were evidenced between Duration of MJS and other related patient- and clinician-reported assessments of RA symptoms and patient functioning, whereas moderate-to-strong correlations were evidenced between these same patient- and clinician-reported assessments and Severity of MJS. Statistically significant differences between the median and mean values of Duration of MJS and Severity of MJS for differing categories of RA disease severity supported known-groups validity. Finally, large and statistically significant differences in change scores from Day 1 to Week 12 for patients defined as responders versus non-responders using the American College of Rheumatology 20 criteria supported the responsiveness of both PROs.Conclusion: Duration of MJS and Severity of MJS PROs demonstrated reliability, validity, and responsiveness in adults with moderately to severely active RA, supporting the measurement of these key symptoms in clinical trials. [ABSTRACT FROM AUTHOR]

Background: To assess the reliability, validity, and responsiveness to treatment change of the single-item measure, Severity of Worst Tiredness, in patients with rheumatoid arthritis (RA).Methods: Data from two Phase 3, randomized, placebo-controlled (RA-BUILD; and active-controlled [RA-BEAM]), clinical studies of the efficacy of baricitinib in adults with moderately to severely active RA were used. The psychometric properties of the single-item measure, Severity of Worst Tiredness, were assessed, including test-retest reliability, convergent and discriminant validity, known-groups validity, and responsiveness, using other patient- and clinician-reported outcomes frequently assessed in RA patients.Results: Test-retest reliability of the Severity of Worst Tiredness was supported through large intraclass correlation coefficients (0.89 ≤ ICC ≤ 0.91). Moderate-to-large correlations were observed between this patient-reported outcome (PRO) and other related patient- and clinician-reported assessments of RA symptoms and patient functioning, supporting construct validity of the measure (│r│ ≥ 0.41). The instrument also displayed known-groups validity through statistically significant differences between mean values of the Severity of Worst Tiredness defined using other indicators of RA severity. Finally, responsiveness was supported by large and statistically significant differences in change scores from Day 1 to Week 12 for patients comparing responders and nonresponders using the American College of Rheumatology 20 (ACR20) criteria.Conclusion: The Severity of Worst Tiredness PRO demonstrated adequate reliability, validity, and responsiveness in clinical trials of adults with moderately to severely active RA and is fit for purpose in this patient population. [ABSTRACT FROM AUTHOR]

Objective: To assess the safety and efficacy of ixekizumab, a monoclonal antibody that inhibits interleukin-17A, in a double-blind phase III trial enrolling patients with active psoriatic arthritis (PsA).Methods: Patients naive to biologic therapy with active PsA were randomised to subcutaneous injections of placebo (N=106), adalimumab 40 mg once every 2 weeks (active reference; N=101), ixekizumab 80 mg once every 2 weeks (IXEQ2W) (N=103), or ixekizumab 80 mg once every 4 weeks (IXEQ4W) (N=107). Both ixekizumab regimens included a 160-mg starting dose. The primary objective was to assess the superiority of IXEQ2W or IXEQ4W versus placebo as measured by the proportion of patients achieving an American College of Rheumatology 20 (ACR20) response at week 24.Results: Significantly more patients treated with ixekizumab achieved an ACR20 response with IXEQ2W (62.1%) or IXEQ4W (57.9%) than placebo (30.2%) (p≤0.001; non-responder imputation method). Disease activity and functional disability were significantly improved with both ixekizumab doses versus placebo at weeks 12 and 24, and there was significantly less progression of structural damage at week 24 (p≤0.01). Clearance of plaque psoriasis was greater with ixekizumab than placebo (p≤0.001). Efficacy results with adalimumab, the active reference arm, showed significant improvements versus placebo. Treatment-emergent adverse events were more frequent with ixekizumab (65.7-66.4%) and adalimumab (64.4%) than placebo (47.2%) (p<0.05).Conclusions: In biologic-naive patients with active PsA, ixekizumab treatment resulted in improvements in disease activity and physical function, as well as in the inhibition of structural damage progression. Overall, adverse events were more frequent in all active groups compared with placebo.Trial Registration Number: NCT01695239; EudraCT2011-002326-49; Results. [ABSTRACT FROM AUTHOR]