Poster Presentation Clinical Oncology Society of Australia 2014 Annual Scientific Meeting

Is bevacizumab in metastatic colorectal cancer effectiveness comparable to key Pharmaceutical Benefits Scheme submission clinical trials? Usage results from five large Queensland public hospitals (#394)

Suzannah Chapman 1 , Daniel McKavanagh 2 , Matthew Burge 1 , Jasotha Sanmugarajah 3 , Jeremy Long 4 , Paul Klages 5 , Ian McPherson 6 , Anita Connor 3 , Julia Hasker 4 , Euan Walpole 2 , Samantha Hollingworth 1
  1. School of Pharmacy, The University of Queensland, Brisbane, QLD, Australia
  2. Princess Alexandra Hospital, Woolloongabba, QLD, Australia
  3. Gold Coast University Hospital, Southport, QLD, Australia
  4. Nambour General Hospital, Nambour, QLD, Australia
  5. Royal Brisbane & Women’s Hospital, Brisbane, QLD, Australia
  6. Toowoomba Health Service, Toowoomba, QLD, Australia

Aims
Randomised clinical trial (RCT) evidence supporting bevacizumab use in metastatic colorectal cancer (mCRC) has shown variable benefits in terms of overall survival (OS; 17-24 months)1-6. In Australia, bevacizumab is government subsidised for treatment of mCRC in combination with first-line chemotherapy, however there is little published evidence of effectiveness for this approach in the Australian context. This project aimed to:
i. collate and analyse the use of bevacizumab in mCRC from the centralised electronic prescribing system (Charm®) at five large metropolitan and regional Queensland public hospitals, and;
ii. to compare this OS to trials used for reimbursement decisions.


Methods
Data was extracted from the Charm® database for mCRC patients assigned to bevacizumab therapy during the period 01/09/2009-31/08/2013. Descriptive statistical analyses including Kaplan-Meier curves were calculated.


Results
During the study period 490 bevacizumab-containing protocols for mCRC were planned, 3750 bevacizumab doses were ordered and 292 patients received at least one bevacizumab dose. 158 patients died. Median patient age was 63yrs, and 58% were male. Patients were distributed into eight different bevacizumab-containing protocol groups, with most (49%) prescribed bevacizumab with oxaliplatin- based chemotherapy. A small number of patients (4%) received treatment beyond disease progression. Median bevacizumab dose was 375mg (2-weekly) and 562.5mg (3-weekly). Median time on treatment was 256 days for the whole cohort. Median overall survival was 17.2 months from first bevacizumab dose.


Conclusions
Bevacizumab use in this cohort of mCRC patients was similar to published RCT results, based on patient and treatment characteristics. The median survival was slightly lower compared to OS in the trials (17-24 months)1-6, possibly explained by shorter follow-up and the methodology (retrospective audit vs controlled prospective trials).

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