Antipsychotic medicines: 24 month review of quetiapine 25 mg
Page last updated: 3 March 2017
Drug utilisation sub-committee (DUSC)
September 2016
Abstract
Purpose
To review the utilisation of PBS listed antipsychotic medicines, including changes in use of 25 mg quetiapine in the 24 months after the restriction was altered to remove repeats from PBS prescriptions.
Listing on the Pharmaceutical Benefits Scheme (PBS)
Quetiapine was listed on 1 November 2000 for schizophrenia, with extensions to the listing to include bipolar disorder from December 2007 and August 2009.
From 1 January 2014, the number of repeats for the listing of 25 mg strength of quetiapine was reduced from five to zero. The clinical criteria for the listing were also changed to include ‘The treatment must be for dose titration purposes’. The PBAC recommended this change because there was evidence of off-label and non-subsidised use of the 25mg strength of quetiapine. A reduction in repeats from five to zero was considered to be sufficient for dose titration in bipolar disease and schizophrenia, and would encourage regular prescriber review for patients treated for non-subsidised indications.
Data Source / methodology
Patient counts and patient level analysis data were extracted from the Department of Human Services (DHS) prescription database for prescriptions supplied from the January 2004 to May 2016. Aggregated prescription data were extracted from the DUSC database (which contains estimates of private and under co-payment prescriptions) for prescriptions supplied from January 2004 to March 2016.
Key Findings
- Growth in the use of typical and atypical antipsychotics had declined. In 2015 there were 438,292 prevalent patients compared to 428,130 in 2014, a year-on-year growth rate of 2.4%. This compared with a year-on-year growth of 4.6% between 2013 and 2014. The slowing in the growth of the prevalent population was mainly attributed to negative growth in the incident population. There were 85,678 patients initiated on an antipsychotic during 2015, which was 1% less than the number of incident patients presenting in 2014 (n=86,552).
- The intervention to change the listing of the 25 mg strength of quetiapine to allow no repeats from 1 January 2014 had been effective in supporting its intended use as a titrating dose for PBS-listed indications.
- Expenditure on all antipsychotics in 2015 was $293.6 million. This was significantly less compared to prior years, largely arising from price reductions which were applied from October 2014.
