Psychometric evaluation of the NTDT-PRO questionnaire for assessing symptoms in patients with non-transfusion-dependent beta-thalassaemia

OBJECTIVES

The non-transfusion-dependent beta-thalassaemia-patient-reported outcome (NTDT-PRO) questionnaire was developed for assessing anaemia-related tiredness/weakness (T/W) and shortness of breath (SoB) among patients with NTDT. Psychometric properties were evaluated using blinded data from the BEYOND trial (NCT03342404).

DESIGN

Analysis of a phase 2, double-blind, randomised, placebo-controlled trial.

SETTING

USA, Greece, Italy, Lebanon, Thailand and the UK.

PARTICIPANTS

Adults (≥18 years) (N=145) with NTDT who had not received a red blood cell transfusion within 8 weeks prior to randomisation, with mean baseline haemoglobin level ≤100 g/L.

MEASURES

NTDT-PRO daily scores from baseline until week 24, and scores at select time points for the 36-Item Short Form Health Survey version 2 (SF-36v2), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) and Patient Global Impression of Severity (PGI-S).

RESULTS

Cronbach's alpha at weeks 13-24 was 0.95 and 0.84 for the T/W and SoB domains, respectively, indicating acceptable internal consistency reliability. Among participants self-reporting no change in thalassaemia symptoms via the PGI-S between baseline and week 1, intraclass correlation coefficients were 0.94 and 0.92 for the T/W and SoB domains, respectively, indicating excellent test-retest reliability. In a known-groups validity analysis, least-squares mean T/W and SoB scores at weeks 13-24 were worse in participants with worse scores for the FACIT-F Fatigue Subscale (FS), SF-36v2 vitality or PGI-S. Indicating responsiveness, changes in T/W and SoB domain scores were moderately correlated with changes in haemoglobin levels, and strongly correlated with changes in SF-36v2 vitality, FACIT-F FS, select FACIT-F items and the PGI-S. Improvements in least-squares mean T/W and SoB scores were higher in participants with greater improvements in scores on other PROs measuring similar constructs.

CONCLUSIONS

The NTDT-PRO demonstrated adequate psychometric properties to assess anaemia-related symptoms in adults with NTDT and can be used to evaluate treatment efficacy in clinical trials.

Psychometric Validation of the Psoriasis Symptoms and Impacts Measure (P-SIM): A Novel Patient-Reported Outcome Instrument for Patients with Plaque Psoriasis, Using Reported Data from the BE RADIANT Phase 3b Trial

Introduction

This analysis assessed the psychometric properties of the Psoriasis Symptoms and Impacts Measure (P-SIM), a novel patient-reported outcome (PRO) tool designed to capture patient experiences of the signs, symptoms and impacts of psoriasis.

Methods

Blinded data from the BE RADIANT phase 3b trial of bimekizumab were analysed. In BE RADIANT, patients were randomised 1:1 to bimekizumab 320 mg every 4 weeks (Q4W) or secukinumab 300 mg (weekly until Week 4, then Q4W). Three items (itching, skin pain and scaling) of the P-SIM were electronically assessed throughout the trial and were scored from 0 to 10 (none to very severe signs/symptoms/impacts). Test–retest reliability was determined using intraclass correlations. Convergent validity was assessed between P-SIM and other relevant PRO and clinician-reported outcome (ClinRO) scores. Known-groups validity was assessed by comparing mean P-SIM item scores between patient subgroups based on the Psoriasis Area and Severity Index (PASI)/Investigator’s Global Assessment (IGA) scores. Responsiveness was assessed via correlations between changes from baseline in P-SIM item scores and other relevant PRO and ClinRO scores. Anchor-based responder analyses and empirical cumulative distribution function (eCDF) curves determined responder thresholds.

Results

The three P-SIM items yielded high intraclass coefficients (> 0.70). By Week 48, the three P-SIM items had moderate (> 0.30 and ≤ 0.50) to strong (> 0.50) correlations with other PROs and weaker correlations with ClinROs, demonstrating good convergent validity. For almost all known-group comparisons, statistically significant between-subgroup score differences were seen across all three P-SIM items. Changes from baseline in the P-SIM and other relevant outcomes were above the acceptable threshold of ≤ 0.30, demonstrating sensitivity to change. Anchor-based analyses determined a ≥ four-point reduction from baseline to indicate marked clinically meaningful improvement for the P-SIM.

Conclusion

These results support the validity, reliability and sensitivity to change of the P-SIM in assessing key symptoms (itching, skin pain and scaling) in patients with moderate to severe plaque psoriasis.

Trial registration

NCT03536884.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-021-01836-1.

Modeling long-term health outcomes of patients with cystic fibrosis homozygous for F508del-CFTR treated with lumacaftor/ivacaftor

BACKGROUND

Lumacaftor/ivacaftor combination therapy is efficacious and generally safe for patients with cystic fibrosis (CF) homozygous for the F508del-CF transmembrane conductance regulator (CFTR) mutation. However, long-term survival benefits of lumacaftor/ivacaftor (LUM/IVA) cannot yet be quantified. Simulation models can provide predictions about long-term health outcomes. In this study, we aimed to project long-term health outcomes of LUM/IVA plus standard care (SC) in patients with CF homozygous for F508del-CFTR.

METHODS

This modeling study was an individual patient simulation in US patients aged ⩾6 years with CF, homozygous for F508del-CFTR. The primary outcome was projected survival among (a) a cohort of patients who ever initiated LUM/IVA, accounting for treatment discontinuations, and (b) a cohort of patients who remain on continuous LUM/IVA. Patient characteristics and model parameters were derived from clinical trials: VX14-809-109, VX13-809-011B, TRAFFIC/TRANSPORT, and PROGRESS; published literature; and the US CF Foundation Patient Registry.

RESULTS

Lumacaftor/ivacaftor + SC is expected to increase median survival by 6.1 years versus SC alone, accounting for treatment discontinuations. The incremental median predicted survival versus SC assuming initiation of LUM/IVA at ages 6, 12, 18, and 25 years was 17.7, 12.6, 8.0, and 3.8 years, respectively. Assuming lifetime treatment with LUM/IVA, incremental median survival was predicted to be 7.8 years longer in the LUM/IVA + SC cohort. Initiating LUM/IVA at ages 6, 12, 18, and 25 years and assuming lifetime treatment resulted in incremental median predicted survival of 23.4, 18.2, 11.0, and 4.8 years, respectively.

CONCLUSIONS

Lumacaftor/ivacaftor is projected to increase survival for patients with CF. Initiation at an early age and treatment persistence result in further increments in projected survival.

Cost-effectiveness analyses in multiple sclerosis: a review of modelling approaches

The growing number of disease-modifying treatments (DMTs) for patients with multiple sclerosis (MS) and the high acquisition costs of these DMTs are likely to increase the demand for information on their cost effectiveness. To improve the comparability and applicability of the findings from future cost-effectiveness analyses, it would be useful to have a clear understanding of the methodological challenges of modelling the cost effectiveness of DMTs in MS and the different approaches taken by such studies to date. In contrast to previous review studies, this review focuses on long-term time horizon (≥10 years) simulation-based cost-effectiveness analyses with homogeneous contexts of analysis (i.e. those with similar study objectives, comparators, and target populations) published over the past decade. By doing so, it provides a clearer picture of how modelling approaches taken in the existing studies truly differ across studies, and reveals major areas for improvement in conducting future cost-effectiveness analyses of DMTs for patients with MS.