Validity and score interpretation of the 12-item Psoriatic Arthritis Impact of Disease: an analysis of pooled data from two phase 3 trials of bimekizumab in patients with psoriatic arthritis.

OBJECTIVES: To investigate psychometric performance of the 12-item Psoriatic Arthritis Impact of Disease (PsAID-12) total and individual item scores in patients with psoriatic arthritis (PsA) and to estimate score change thresholds and scores corresponding to different levels of symptom/impact severity. METHODS: Data up to week 16 from 1252 patients with active PsA enrolled in two randomised controlled trials of bimekizumab (BE OPTIMAL (NCT03895203) and BE COMPLETE (NCT03896581)) were used to assess construct validity (correlations with other patient-reported outcomes), known-groups validity (based on Minimal Disease Activity index, Disease Activity Index for Psoriatic Arthritis and Psoriatic Arthritis Disease Activity Score), reliability (Cronbach's alpha and intraclass correlation coefficients (ICCs)) and responsiveness (sensitivity to change). Clinically meaningful within-patient improvement thresholds were estimated by anchor-based and distribution-based analyses, and symptom/impact severity thresholds were estimated by receiver operating characteristic curve analyses. RESULTS: The mean (SD) PsAID-12 total score at baseline was 4.19 (1.94). PsAID-12 scores demonstrated good convergent validity and good known-groups validity. Internal consistency reliability (Cronbach's alpha 0.95) and test-retest reliability (ICC ≥ 0.70) were also good. Responsiveness was acceptable (correlations ≥0.30 for most scores). Improvement thresholds were estimated at 1.5-2 points for the PsAID-12 total score and 2 or 3 points for item scores. Thresholds for different levels of symptom/impact severity could be derived for most PsAID-12 items. CONCLUSIONS: The PsAID-12 demonstrated robust psychometric properties in a large sample of patients with active PsA, supporting its use as a fit-for-purpose patient-reported outcome in this population. Furthermore, thresholds for score interpretation were derived.

Calibration and validation of modeled 5-year survival predictions among people with cystic fibrosis treated with the cystic fibrosis transmembrane conductance regulator modulator ivacaftor using United States registry data.

OBJECTIVES: Cystic fibrosis (CF) is a rare genetic disease characterized by life-shortening lung function decline. Ivacaftor, a CF transmembrane conductance regulator modulator (CFTRm), was approved in 2012 for people with CF with specific gene mutations. We used real-world evidence of 5-year mortality impacts of ivacaftor in a US registry population to validate a CF disease-progression model that estimates the impact of ivacaftor on survival. METHODS: The model projects the impact of ivacaftor vs. standard care in people with CF aged ≥6 years with CFTR gating mutations by combining parametric equations fitted to historical registry survival data, with mortality hazards adjusted for fixed and time-varying person-level characteristics. Disease progression with standard care was derived from published registry studies and the expected impact of ivacaftor on clinical characteristics was derived from clinical trials. Individual-level baseline characteristics of the registry ivacaftor-treated population were entered into the model; 5-year model-projected mortality with credible intervals (CrIs) was compared with registry mortality to evaluate the model's validity. RESULTS: Post-calibration 5-year mortality projections closely approximated registry mortality in populations treated with standard care (6.4% modeled [95% CrI: 5.3% to 7.6%] vs. 6.0% observed) and ivacaftor (3.4% modeled [95% CrI: 2.7% to 4.4%] vs. 3.1% observed). The model accurately predicted 5-year relative risk of mortality (0.53 modeled [0.47 to 0.60] vs. 0.51 observed) in people treated with ivacaftor vs. standard care. CONCLUSIONS: Modeled 5-year survival projections for people with CF initiating ivacaftor vs. standard care align closely with real-world registry data. Findings support the validity of modeling CF to predict long-term survival and estimate clinical and economic outcomes of CFTRm.

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.

Impact of Lenalidomide Treatment on Overall Survival in Patients With Lower-Risk, Transfusion-Dependent Myelodysplastic Syndromes.

BACKGROUND: For patients with lower-risk (LR) myelodysplastic syndromes (MDS), overall survival (OS) is rarely a primary clinical trial endpoint. Treatments such as lenalidomide can reduce red blood cell (RBC) transfusion burden (TB) and serum ferritin, but the long-term impact on OS remains undetermined. PATIENTS AND METHODS: Data from 3 trials evaluating lenalidomide in patients with LR-MDS (the phase 2 MDS-003 and phase 3 MDS-004 trials in del[5q]; the phase 3 trial MDS-005 in non-del[5q] patients) were pooled. Predictors of OS were assessed by multivariate analysis using time-dependent models for TB and RBC transfusion independence (RBC-TI), and a landmark analysis of RBC-TI at 17 weeks. Separate analyses using MDS-004 and MDS-005 data determined the relationship between OS and serum ferritin. RESULTS: Median follow-up for MDS-003, MDS-004, and MDS-005 was 3.2, 3.0, and 1.7 years, respectively. In multivariate analyses, transfusion of ≥6 RBC units over 8 weeks was a significant predictor of shorter OS vs. 0 units in the time-dependent TB model (hazard ratio [HR] 4.65; 95% confidence interval [CI] 3.32-6.52; P < .0001). RBC-TI achievement was associated with prolonged OS in the time-dependent (HR 0.48; 95% CI 0.37-0.62; P < .0001) and landmark model (HR 0.57; 95% CI 0.44-0.75; P < .0001). Increased serum ferritin was associated with shorter OS (P < .0001). CONCLUSION: This analysis of prospective trial data in patients with LR-MDS confirms lenalidomide may improve OS by reducing TB and serum ferritin. OS should be considered as an endpoint in future lower risk MDS 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 Data from the BE VIVID and BE READY Phase 3 Trials.

INTRODUCTION: Plaque psoriasis can significantly impact patients' quality of life. We assessed psychometric properties of the Psoriasis Symptoms and Impacts Measure (P-SIM), developed to capture patients' experiences of signs, symptoms and impacts of psoriasis. METHODS: Pooled, blinded, 16-week data from 1002 patients in the BE VIVID and BE READY bimekizumab phase 3 trials were analysed. The suitability of the P-SIM missing score rule (weekly scores considered missing if ≥ 4 daily scores were missing) was assessed. Test-retest reliability was evaluated using intraclass correlation coefficients (ICCs). Convergent validity was assessed between P-SIM and relevant patient-reported outcome (PRO) (Dermatology Life Quality Index [DLQI], DLQI item 1 [skin symptoms], Patient Global Assessment of Psoriasis) and clinician-reported outcome (ClinRO) scores (Psoriasis Area and Severity Index [PASI], Investigator's Global Assessment [IGA]) at baseline and week 16. Known-groups validity was assessed, comparing P-SIM scores between patient subgroups predefined using PASI/IGA scores. Sensitivity to change over 16 weeks was evaluated; responder definition (RD) thresholds were explored. RESULTS: The missing score rule used did not impact P-SIM scores. Test-retest reliability analyses demonstrated excellent score reproducibility (ICC 0.91-0.98). Inter-item correlations at baseline and week 16 were strong (> 0.5), apart from "choice of clothing" with "skin pain" and "burning" at baseline (both 0.49). All P-SIM scores were moderately to strongly correlated with other outcomes, demonstrating convergent validity, apart from ClinROs (PASI, IGA) at baseline that had low variability. P-SIM scores discriminated known groups at week 16, confirming known-groups validity. Changes from baseline to week 16 in P-SIM and other clinically relevant outcomes were strongly correlated (> 0.5; weaker with ClinROs), establishing sensitivity to change. Anchor-based RD analyses determined a four-point P-SIM item score decrease as indicative of marked clinically meaningful improvement. CONCLUSION: P-SIM scores demonstrated good reliability, validity and sensitivity to change. A four-point RD threshold could be used to assess 16-week treatment effects. TRIAL REGISTRATION: BE VIVID: NCT03370133; BE READY: NCT03410992.

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.

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 of Pomalidomide, Carfilzomib, and Daratumumab for the Treatment of Patients with Heavily Pretreated Relapsed-refractory Multiple Myeloma in the United States.

PURPOSE: Pomalidomide plus low-dose dexamethasone (POM-d), daratumumab monotherapy (DARA), and carfilzomib monotherapy (CAR) have been approved for use in the treatment of patients with heavily pretreated relapsed-refractory multiple myeloma (RRMM) in the US, based on findings from the MM-002, SIRIUS, and PX-171-003-A1 studies, respectively. The objective of this study was to assess the cost-effectiveness of POM-d, DARA, and CAR in this patient population from a US payer's perspective. METHODS: A cost-effectiveness model was developed to estimate the cost and health outcomes over a 3-year time horizon in 3 health states: progression-free, post-progression, and death. The main efficacy data source was a matching-adjusted indirect comparison using data from the aforementioned studies. Direct medical costs were considered, including: treatment acquisition and administration (initial line and subsequent line), pre- and post-medication, prophylaxis treatment, adverse event management, and health care resource utilization. Sensitivity analyses were conducted. A scenario analysis that assumed equal efficacy across all 3 treatments was conducted. Costs, life-years, and quality-adjusted life-years were estimated and discounted at 3% per annum. FINDINGS: Over 3 years, the use of POM-d was associated with similar life-years and quality-adjusted life-years gained compared with DARA and CAR (incremental: life-years, +0.02 and +0.07, respectively; quality-adjusted life-years, +0.01 and +0.05), and with a cost less than that of DARA (-$8,919) and similar to that of CAR (-$195). Sensitivity analyses illustrated that the results were sensitive to progression-free survival, treatment duration, and drug costs. An equal efficacy scenario resulted in cost-savings relative to those of both DARA and CAR (-$11,779 and -$12,595). IMPLICATIONS: POM-d may be a cost-effective treatment option relative to DARA or CAR in heavily pretreated patients with RRMM in the US.

Modeling economic implications of alternative treatment strategies for acute bacterial skin and skin structure infections.

OBJECTIVE: The economic implications from the US Medicare perspective of adopting alternative treatment strategies for acute bacterial skin and skin structure infections (ABSSSIs) are substantial. The objective of this study is to describe a modeling framework that explores the impact of decisions related to both the location of care and switching to different antibiotics at discharge. METHODS: A discrete event simulation (DES) was developed to model the treatment pathway of each patient through various locations (emergency department [ED], inpatient, and outpatient) and the treatments prescribed (empiric antibiotic, switching to a different antibiotic at discharge, or a second antibiotic). Costs are reported in 2012 USD. RESULTS: The mean number of days on antibiotic in a cohort assigned to a full course of vancomycin was 11.2 days, with 64% of the treatment course being administered in the outpatient setting. Mean total costs per patient were $8671, with inpatient care accounting for 58% of the costs accrued. The majority of outpatient costs were associated with parenteral administration rather than drug acquisition or monitoring. Scenarios modifying the treatment pathway to increase the proportion of patients receiving the first dose in the ED, and then managing them in the outpatient setting or prescribing an oral antibiotic at discharge to avoid the cost associated with administering parenteral therapy, therefore have a major impact and lower the typical cost per patient by 11-20%. Since vancomycin is commonly used as empiric therapy in clinical practice, based on these analyses, a shift in treatment practice could result in substantial savings from the Medicare perspective. CONCLUSIONS: The choice of antibiotic and location of care influence the costs and resource use associated with the management of ABSSSIs. The DES framework presented here can provide insight into the potential economic implications of decisions that modify the treatment pathway.

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.