PWE-249 Impact of switching from a brand to a generic macrogol on prescriptions and doses for patients with chronic constipation in the UK
Authors: V Bajaj, A Naidoo
Journal: Gut (2015)

<h3>Introduction</h3> Patients with constipation switching from a branded to a generic macrogol may require a higher number of prescriptions (i.e. scripts) and doses (defined as packs of 20 sachets). Repeated switching on the basis of cost savings alone can irritate patients and can erode trust and compliance (GPC 2013<sup>1</sup>). This analysis compares the number of prescriptions and doses for patients with chronic constipation who switched from a branded macrogol (MOVICOL<sup>®</sup>) to a generic macrogol (LAXIDO<sup>®</sup>), and those who switched back to the branded macrogol. <h3>Method</h3> Retrospective real world, longitudinal patient and prescribing data were collected from 397 GP practices (2,186 GPs and 13,567 patients in the database during the period Jan to Dec 2013) across the UK (sourced from Cegedim Strategic Data Ltd.). Two patient cohorts were selected for the analysis: (1) patients with chronic constipation prescribed the branded macrogol who switched to the generic; and (2) patients with chronic constipation prescribed the branded macrogol, who switched to the generic and returned to the brand. Patients in each cohort were tracked from initiation to end of treatment. The change in annualised prescriptions and doses per patient in each cohort were analysed using the one- and two-sided t-test for two-sample assuming unequal variances. <h3>Results</h3> Males and females aged ≥13 years were included in the analysis. <h3>Patient</h3> Cohort (1), N=3109, M=0.63, SD=8.29, chronic patients initiated on the brand and switched to the generic, showed on average an increased number of prescriptions (+8%) and doses (+13%) per patient per year. The +0.6 and +1.7 absolute increase in number of prescriptions and doses respectively were significant (p &lt; 0.05), and observed across all age groups (elderly [65+], middle-aged [36–64], young adult [19–35], and adolescent [13–18]). <h3>Patient</h3> Cohort (2), N=91, M=−3.41, SD=1.65, chronic patients initiated on the brand who switched to the generic (Switch 1) and switched back to the brand (Switch 2), showed on average a reduced number of prescriptions (−24%) and doses (−11%) per patient per year during Switch 2. In addition, the +5.0 and +4.9 absolute increase in number of prescriptions and doses at Switch 1 from the branded to generic macrogol was significant (p &lt; 0.05). <h3>Conclusion</h3> Amongst patients with chronic constipation, those who switched away from the branded to a generic macrogol required a significantly higher number of prescriptions and doses than they had been used to having. Conversely, patients who were switched back from the generic to the branded macrogol required fewer. Factors impacting changes in prescription for example, efficacy, convenience, and compliance require further investigation. <h3>Disclosure of interest</h3> V. Bajaj Employee of: Norgine Limited, A. Naidoo Employee of: Norgine Limited. <h3>Reference</h3> Prescribing in General Practice, General Practitioners Committee (GPC), BMA, May 2013