Vicky R Copley

Comparing new treatments for idiopathic pulmonary fibrosis – a network meta-analysis

BackgroundThe treatment landscape for idiopathic pulmonary fibrosis, a devastating lung disease, is changing. To investigate the effectiveness of treatments for idiopathic pulmonary fibrosis we undertook a systematic review, network meta-analysis and indirect comparison.MethodsWe searched MEDLINE, EMBASE and The Cochrane library for relevant studies. Randomised controlled trials of pirfenidone, nintedanib or N-acetylcysteine were eligible. Predefined processes for selecting references, extracting data and assessing study quality were applied. Our network meta-analysis of published data used a fixed effect model. For forced vital capacity measures a standardised mean difference approach was used and converted to odds ratios for interpretation.ResultsOf 1076 references, 67 were retrieved and 11 studies included. Studies were of reasonable size, populations were similar, and the overall quality was good. Only two treatments, pirfenidone (odds ratio 0.62, 95% credible interval 0.52, 0.74) and nintedanib (0.41, 95% credible interval 0.34, 0.51) produced a statistically significant slowing in the rate of forced vital capacity decline compared with placebo. In an indirect comparison, results indicate that nintedanib is statistically significantly better than pirfenidone in slowing forced vital capacity decline (odds ratio 0.67, 95% credible interval 0.51, 0.88). Results were stable in scenario analysis and random effects models. Indirect comparisons of mortality were not statistically significant between nintedanib and pirfenidone.ConclusionsTwo treatments show beneficial effects and when compared indirectly nintedanib appears to have superior benefit on forced vital capacity. Limitations to indirect comparisons should be considered when interpreting these results, however, our findings can be useful to inform treatment decisions.

The effectiveness and cost-effectiveness of treatments for idiopathic pulmonary fibrosis: systematic review, network meta-analysis and health economic evaluation

BackgroundIdiopathic pulmonary fibrosis (IPF) is a life-limiting lung disease with considerable impact on patients and carers as the disease progresses. Currently few treatments are available. We aimed to evaluate the clinical and cost-effectiveness of available treatments for IPF.MethodsSystematic reviews of clinical effectiveness, quality of life and cost effectiveness were undertaken. Eleven bibliographic databases were searched from inception to July 2013 and studies were assessed for eligibility against a set of pre-defined criteria. Two reviewers screened references, extracted data from included studies and appraised their quality. An advisory group was consulted about the choice of interventions. A narrative review was undertaken and where feasible fixed effect and random effects meta-analysis were undertaken including a network meta-analysis (NMA).A decision-analytic Markov model was developed to estimate cost-effectiveness of pharmacological treatments for IPF. Following best practice recommendations, the model perspective was of the national health service and personal social services, a discount rate of 3.5% for costs and health benefits was applied and outcomes were expressed as cost per quality adjusted life-year gained. Parameter values were obtained from the NMA and systematic reviews. Sensitivity analyses were undertaken.ResultsFourteen studies were included in the review of clinical effectiveness, of which one evaluated azathioprine, three N-acetylcysteine [NAC] (alone or in combination), four pirfenidone, one nintedanib, one sildenafil, one thalidomide, two pulmonary rehabilitation, and one a disease management programme. Study quality was generally good. Evidence suggests that some effective treatments are available. In NMA only nintedanib and pirfenidone show statistically significant improvements. The model results show increased survival for five pharmacological treatments (NAC triple therapy, inhaled NAC, nintedanib, pirfenidone, and sildenafil) compared with best supportive care, at increased cost. Only inhaled NAC was cost-effective at current willingness to pay thresholds but it may not be clinically effective.ConclusionsFew interventions have any statistically significant effect and the cost-effectiveness of treatments is uncertain. A lack of studies on palliative care approaches was identified and there is a need for further research into pulmonary rehabilitation and thalidomide in particular. A well conducted RCT on inhaled NAC therapy should also be considered.

The clinical effectiveness and cost-effectiveness of treatments for idiopathic pulmonary fibrosis: a systematic review and economic evaluation

BACKGROUND Idiopathic pulmonary fibrosis (IPF) is a life-limiting lung disease that generally affects people over 60 years old. The main symptoms are shortness of breath and cough, and as the disease progresses there is a considerable impact on day-to-day life. Few treatments are currently available. OBJECTIVES To conduct a systematic review of clinical effectiveness and an analysis of cost-effectiveness of treatments for IPF based on an economic model informed by systematic reviews of cost-effectiveness and quality of life. DATA SOURCES Eleven electronic bibliographic databases, including MEDLINE, EMBASE, Web of Science, and The Cochrane Library and the Centre for Reviews and Dissemination databases, were searched from database inception to July 2013. Reference lists of relevant publications were also checked and experts consulted. METHODS Two reviewers independently screened references for the systematic reviews, extracted and checked data from the included studies and appraised their risk of bias. An advisory group was consulted about the choice of interventions until consensus was reached about eligibility. A narrative review with meta-analysis was undertaken, and a network meta-analysis (NMA) was performed. A decision-analytic Markov model was developed to estimate cost-effectiveness of pharmacological treatments for IPF. Parameter values were obtained from NMA and systematic reviews. Univariate and probabilistic sensitivity analyses were undertaken. The model perspective is NHS and Personal Social Services, and discount rate is 3.5% for costs and health benefits. RESULTS Fourteen studies were included in the review of clinical effectiveness, of which one evaluated azathioprine, three N-acetylcysteine (NAC) (alone or in combination), four pirfenidone, one BIBF 1120, one sildenafil, one thalidomide, two pulmonary rehabilitation, and one a disease management programme. Study quality was generally good, with a low risk of bias. The current evidence suggests that some treatments appear to be clinically effective. The model base-case results show increased survival for five pharmacological treatments, compared with best supportive care, at increased cost. General recommendations cannot be made of their cost-effectiveness owing to limitations in the evidence base. LIMITATIONS Few direct comparisons of treatments were identified. An indirect comparison through a NMA was performed; however, caution is recommended in the interpretation of these results. In relation to the economic model, there is an assumption that pharmacological treatments have a constant effect on the relative rate of per cent predicted forced vital capacity decline. CONCLUSIONS Few interventions have any statistically significant effect on IPF and a lack of studies on palliative care approaches was identified. Research is required into the effects of symptom control interventions, in particular pulmonary rehabilitation and thalidomide. Other research priorities include a well-conducted randomised controlled trial on inhaled NAC therapy and an updated evidence synthesis once the results of ongoing studies are reported. STUDY REGISTRATION This study is registered as PROSPERO CRD42012002116. FUNDING The National Institute for Health Research Health Technology Assessment programme.