Prucalopride for the treatment of women with chronic constipation in whom standard laxative regimens have failed to provide adequate relief

Abstract

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of prucalopride for the treatment of women with chronic constipation in whom standard laxative regimens have failed to provide adequate relief. The ERG report is based on the manufacturer's submission (MS) to the National Institute for Health and Clinical Excellence as part of the single technology appraisal process. In the submission, quality-of-life data [Patient Assessment of Constipation Quality of Life (PAC-QOL) and Patient Assessment of Constipation Symptoms (PAC-SYM) questionnaires] from trials of prucalopride were extrapolated to EQ-5D (European Quality of Life-5 Dimensions) data and used to inform effectiveness in an economic model. Response rates to prucalopride were derived from observed response rates in trials, defined as the proportion of patients achieving an average of three or more spontaneous complete bowel movements over the 4- or 12-week trial periods. Adult (18-64 years) and elderly (≥ 65 years) patients were considered separately in the model. Cost-effectiveness was determined from estimated improvements in EQ-5D and anticipated response rates, adjusted for baseline severity of chronic constipation. The ERG considered that the patients participating in these trials were not representative of those in the licensed indication. They were not all refractory to laxatives, and baseline EQ-5D scores showed a large spread in quality of life, with many patients experiencing little baseline dissatisfaction. The mapping of quality-of-life data from trials (PAC-QOL and PAC-SYM data) to EQ-5D was unclear and invalidated. The assumption of the long-term effectiveness and safety of prucalopride to 1 year was considered unjustified. There was no justification or sources given for coefficients used to predict effectiveness in the economic model, and no costs other than the cost of prucalopride were incorporated into the model. Owing to the many areas of uncertainty, particularly the effectiveness of prucalopride in the licensed patient group and its long-term effectiveness and safety, it was considered that the MS provided no evidence for whether prucalopride is effective or not in women with laxative-refractory chronic constipation. Further subgroup analysis of the actual patient group of interest may have better guided decision-making. However, long-term efficacy data, with validated estimates of quality of life incorporated in a well-founded model, would be important for an evidence-based judgement to be made.