Clinical and cost-effectiveness of epoprostenol, iloprost, bosentan, sitaxentan and sildenafil for pulmonary arterial hypertension within their licensed indications: a systematic review and economic evaluation.

OBJECTIVE(S): To investigate the clinical and cost-effectiveness of epoprostenol, iloprost, bosentan, sitaxentan and sildenafil for the treatment of adults with pulmonary arterial hypertension (PAH) within their licensed indications. DATA SOURCES: Major electronic databases (including the Cochrane Library, MEDLINE and EMBASE) were searched up to February 2007. Further data were obtained from dossiers submitted to NICE by the manufacturers of the technologies. REVIEW METHODS: The systematic clinical and economic reviews were conducted according to accepted procedures. Model-based economic evaluations of the cost-effectiveness of the technologies from the perspective of the UK NHS and personal social services were carried out. RESULTS: In total, 20 randomised controlled trials (RCTs) were included in this assessment, mostly of 12-18 weeks duration and comparing one of the technologies added to supportive treatment with supportive treatment alone. Four published economic evaluations were identified. None produced results generalisable to the NHS. There was no consensus in the industry submissions on the most appropriate model structure for the technology assessment. Improvement in 6-minute walk distance (6MWD) was seen with intravenous epoprostenol in primary pulmonary hypertension (PPH) patients with mixed functional class (FC) (mainly III and IV, licensed indication) compared with supportive care (58 metres; 95% CI 6-110). For bosentan compared with supportive care, the pooled result for improvement in 6MWD for FCIII patients with mixed PAH (licensed indication) was 59 metres (95% CI 20-99). For inhaled iloprost, sitaxentan and sildenafil no stratified data for improvement in 6MWD were available. The odds ratio (OR) for FC deterioration at 12 weeks was 0.40 (95% CI 0.13-1.20) for intravenous epoprostenol compared with supportive care. The corresponding values for inhaled iloprost (FCIII PPH patients; licensed indication), bosentan, sitaxentan (FCIII patients with mixed PAH; licensed indication) and sildenafil (FCIII patients with mixed PAH; licensed indication) were 0.29 (95% CI 0.07-1.18), 0.21 (95% CI 0.03-1.76), 0.18 (95% CI 0.02-1.64) and [Commercial-in-confidence information has been removed] respectively. The incremental cost-effectiveness ratios (ICERs) for the technologies plus supportive care compared with supportive care alone, determined by independent economic evaluation, were 277,000 pounds/quality-adjusted life-year (QALY) for FCIII and 343,000 pounds/QALY for FCIV patients for epoprostenol, 101,000 pounds/QALY for iloprost, 27,000 pounds/QALY for bosentan and 25,000 pounds/QALY for sitaxentan. For the most part sildenafil plus supportive care was more effective and less costly than supportive care alone and therefore dominated supportive care. In the case of epoprostenol the ICERs were sensitive to the price of epoprostenol and for bosentan and sitaxentan the ICERs were sensitive to running the model over a shorter time horizon and with a lower cost of epoprostenol. Two RCTs directly compared the technologies against each other with no significant differences observed between the technologies. Combinations of technologies were investigated in four RCTs, with some showing conflicting results. CONCLUSION(S): All five technologies when added to supportive treatment and used at licensed dose(s) were more effective than supportive treatment alone in RCTs that included patients of mixed FC and types of PAH. Current evidence does not allow adequate comparisons between the technologies nor for the use of combinations of the technologies. Independent economic evaluation suggests that bosentan, sitaxentan and sildenafil may be cost-effective by standard thresholds and that iloprost and epoprostenol may not. If confirmed, the use of the most cost-effective treatment would result in a reduction in costs for the NHS. Long-term, double-blind RCTs of sufficient sample size that directly compare bosentan, sitaxentan and sildenafil, and evaluate outcomes including survival, quality of life, maintenance on treatment and impact on the use of resources for NHS and personal social services are needed.

The responsiveness and validity of the CAMPHOR Utility Index.

The aim of the present study was to validate and determine the minimal important difference (MID) and responsiveness of the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) Utility Index, a new tool enabling cost utility analyses. CAMPHOR, 6-min walking test (6MWT) and New York Heart Association (NYHA) data for 869 pulmonary hypertension patients (545 (63%) female; mean+/-SD age 56.6+/-15.4 yrs) from three centres were analysed. Utility was correlated with 6MWT data and calculated by NYHA class to assess validity. Effect sizes were calculated for those with two CAMPHOR assessments. Distribution and anchor-based MIDs were calculated. Analyses were carried out in patients receiving bosentan in order to determine whether or not those remaining in NYHA class III following treatment improved. The Utility Index distinguished between adjacent NYHA classes and correlated with 6MWT results. CAMPHOR subscales and utility were as responsive as the 6MWT (effect sizes ranged 0.31-0.69 for the CAMPHOR and 0.16-0.34 for the 6MWT). The within-group MID for the Utility Index was estimated to be approximately 0.09. Patients remaining in NYHA class III experienced, on average, a significant improvement (CAMPHOR Utility Index and functioning), which exceeded the MID. The CAMPHOR Utility Index is valid and responsive to change. Patients can experience significant and important improvements even if they do not improve on the basis of traditional outcomes, such as NYHA functional class.

Semi-quantitative assessment of tricuspid regurgitation on contrast-enhanced multidetector CT.

AIM: To assess whether the early regurgitation of intravenous contrast medium into the inferior vena cava (IVC) and/or hepatic veins on computed tomography (CT), indicates tricuspid regurgitation (TR), and if so, whether it be used to grade severity. MATERIALS AND METHODS: We identified 86 consecutive patients that had been investigated for possible pulmonary endarterectomy at Papworth Hospital. From these, 61 patients were selected in whom CT, transthoracic echocardiography, and right heart catheterization (RHC) had been performed within 6 weeks. Using an arbitrary visual scale, the degree of TR assessed by intravenous contrast-enhanced CT was compared with echocardiography. Results were analysed using a kappa weighted statistical test. In addition, CT and echocardiographic assessments of TR severity were correlated with pulmonary artery pressure measurements obtained by RHC (Spearman's rank correlation coefficient). RESULTS: CT assessment of TR had a sensitivity of 90.4% and a specificity of 100% in detecting echocardiographic TR. For TR graded as more than trivial by echocardiography, sensitivity of CT was 100%. With respect to RHC data, the correlation between severity assessment of TR between CT and echocardiography using the Kappa weighted coefficient was 0.56 (moderately good agreement). With respect to RHC data, the correlation between mean pulmonary pressure and TR grading on CT and echocardiography was r = 0.685 (p < 0.001) and r = 0.727 (p < 0.001), respectively. CONCLUSION: Early opacification of the IVC or hepatic veins on first-pass contrast-enhanced CT almost invariably indicates TR. There is moderately good agreement between CT and echocardiographic assessment of the severity of TR. Both CT and echocardiographic grading of TR correlate well with RHC measurements of pulmonary artery pressure.

Role of computed tomographic scanning of the thorax prior to bronchoscopy in the investigation of suspected lung cancer.

BACKGROUND: Fibreoptic bronchoscopy (FOB) is the usual initial investigation of choice in patients with suspected endobronchial carcinoma, but it is often non-diagnostic. Once a positive diagnosis has been made, many patients undergo staging by computed tomographic (CT) scanning to assess the extent of the disease and its suitability for radical treatment. To determine whether initial CT scanning before FOB is a cost effective way of reducing subsequent unnecessary or unhelpful invasive diagnostic procedures, a study was undertaken in 171 patients with suspected endobronchial carcinoma. METHODS: A randomised two group study was performed with all patients undergoing an initial CT staging scan. In group A the CT scans were reviewed before FOB, allowing cancellation or a change to an alternative invasive procedure if considered appropriate. In group B all patients proceeded to FOB with the bronchoscopist blinded to the result of the CT scan until after the procedure. RESULTS: In group A six of 90 patients (7%) required no further investigations as the CT scan was either normal, consistent with benign disease, or consistent with widespread metastatic disease. Of the remainder, bronchoscopy was diagnostic in 50 of 68 (73%) in group A compared with 44 of 81 (54%) in group B (p = 0.015). Overall, a positive diagnosis was made after a single invasive investigation in 64 of 84 patients (76%) in group A compared with only 45 of 81 patients (55%) in group B (p = 0.005). Only seven of 90 patients (8%) in group A required more than one invasive investigation compared with 15 of 81 patients (18.5%) in group B. In patients with malignancy, bronchoscopy was more likely to be diagnostic in group A (50 of 56 patients (89%)) than in group B (44 of 62 (71%); p = 0. 012), and the diagnosis was more frequently made on the initial invasive investigation (group A, 63 of 70 (90%); group B, 44 of 62 (71%); p = 0.004). Because of the lower number of invasive procedures performed in group A than in group B, the cost of performing CT scans before FOB in all patients in group A would have equated to a projected cost of performing CT scans in 60% of patients after FOB in group B. CONCLUSIONS: Performing initial CT thoracic scans before bronchoscopy in patients with suspected endobronchial malignancy is a cost effective way of improving diagnostic yield from invasive diagnostic procedures and occasionally may obviate the need for any further investigation.