ABSTRACT
BACKGROUND: Proprotein convertase subtilisin/kexin type 9 inhibitors, such as evolocumab, are cholesterol-lowering drugs effective in lowering lipid levels in high-risk patients with primary hypercholesterolemia or mixed dyslipidemia. OBJECTIVE: This study assessed the cost effectiveness of evolocumab in combination with lipid-lowering therapies (LLTs) compared with LLTs alone, from a public healthcare perspective in the Kingdom of Saudi Arabia (KSA). METHODS: A Markov cohort state transition model was used, incorporating efficacy estimates from the FOURIER clinical trial and baseline cardiovascular event rates observed in clinical practice. Other model inputs were extracted from the literature and Saudi sources. RESULTS: In patients with clinically evident atherosclerotic cardiovascular disease and baseline low-density lipoprotein cholesterol ≥ 70 or ≥ 100 mg/dL, adding evolocumab to a maximally tolerated statin, with or without ezetimibe, was associated with incremental cost-effectiveness ratios (ICERs) of Saudi Arabian riyal (SAR) 109,274 ($US60,708) per quality-adjusted life-year (QALY) gained and SAR75,163 ($US41,757) per QALY gained, respectively. The ICER was SAR22,391 ($US12,440) per QALY gained in patients with heterozygous familial hypercholesterolemia. Sensitivity analysis results were robust to changes in model parameters and fell below the willingness-to-pay threshold of up to three times gross domestic product per capita in 2019 (SAR264,813 [$US147,118]). CONCLUSION: Evolocumab can be considered a cost-effective treatment option for patients with atherosclerotic cardiovascular disease or heterozygous familial hypercholesterolemia in the KSA.
ABSTRACT
OBJECTIVE: The objective of this study was to evaluate the cost effectiveness of lubiprostone, prucalopride, placebo and immediate referral to secondary care in chronic idiopathic constipation (CIC) in an economic model that was used by the UK National Institute for Health and Care Excellence (NICE) in developing guidance. METHODS: We developed a cohort state-transition model to reflect the treatment pathway in CIC from the UK NHS and personal social services perspective. Time on treatment was determined by a treatment continuation rule using data from an indirect comparison and survival curves fitted to long-term data. Quality of life was defined by whether CIC was resolved or unresolved, using published values. Costs were determined by drug acquisition costs, invasive procedures and healthcare resource use (associated with resolved or unresolved CIC), using published UK sources. Deterministic and probabilistic sensitivity analyses were conducted. RESULTS: Over a 10-year time horizon, lubiprostone was more costly and more effective than placebo and immediate referral to secondary care, with incremental cost-effectiveness ratios (ICERs) of £58,979 and £21,152. Lubiprostone dominated prucalopride in the base case and with a time horizon of 1 year. The main sensitivity for the comparison against placebo was the assumptions around placebo cost and efficacy. The main sensitivity for the comparison against prucalopride was the endpoint used in the indirect comparison. CONCLUSION: Lubiprostone may be cost effective compared with prucalopride or immediate referral but not compared with placebo in the base case. The implementation of the guidance issued by NICE should increase quality of life for patients with CIC and provide a further treatment option.
ABSTRACT
AIMS: The primary aim of this study was to perform a mapping of the EORTC-QLQ-C30 scores to EQ-5D-3L for the SIRFLOX study; a large dataset of patients with previously untreated liver-only or liver-dominant metastatic colorectal cancer (mCRC). A secondary aim was to compare the predictive validity of existing mappings from EORTC-QLQ-C30 to EQ-5D-3L conducted in other cancers. METHODS AND MATERIALS: Questionnaires (completed within 529 patients) were used in a linear mixed regression to model EQ-5D-3L utility values (scored using the UK tariff) as a function of the five function scores, nine symptom scores, and the global score from the EORTC-QLQ-C30 questionnaire. A Tobit regression was also performed. The mean EQ-5D-3L values for the SIRFLOX trial were calculated and compared with predicted EQ-5D-3L values derived using published mapping algorithms. RESULTS: The linear mixed regression model provided a satisfactory mapping between the EORTC-QLQ-C30 and the EQ-5D-3L, whilst the Tobit model did not perform as well. When utilities from the SIRFLOX data were calculated with previously published mapping studies, three out of five studies performed well (< 10% mean difference). LIMITATIONS: The main limitation of the study was the lack of meaningful observations post-progression (67 paired observations). For this reason, this study was unable to test whether the mapping holds by disease stage. Additionally, although the study adds to the literature of mappings to the EQ-5D-3L, it is not known how results would differ using the EQ-5D-5L. CONCLUSION: This study is the first of its kind in liver-only or liver-dominant mCRC, and mCRC in general. The mapping constructed showed a good fit to the data and provides practitioners with an additional mapping between EORTC-QLQ-C30 to EQ-5D-3L using a large dataset (529 patients, 707 paired observations). The study also confirmed the generalizability of mappings published by Proskorovsky, Kontodimopoulos, and Longworth to liver-only or liver-dominant mCRC.
