Verification of imatinib cost-effectiveness in advanced gastrointestinal stromal tumor in British Columbia (VINCE-BC study).
BACKGROUND
This cost-effectiveness analysis of imatinib in British Columbia Cancer Agency (BCCA) patients with advanced gastrointestinal stromal tumors (GIST) was performed to justify funding.


METHODS
A pragmatic, retrospective review identified BCCA patients with advanced GIST who received imatinib or historical treatment during successive, pre-specified time periods. Primary outcome was the cost-effectiveness (CE) of imatinib based on median overall survival (MOS). Secondary outcomes were cost-effectiveness based on median progression-free survival (PFS) and comparison to literature efficacy. This study took the BCCA perspective. Sensitivity analyses varying effectiveness over the 95% confidence interval (CI), cost to its extremes, discounting level at 0, 3, and 5%, and substituting life expectancy for MOS were performed.


RESULTS
Forty-six and 47 patients in the imatinib and historical groups respectively showed MOS with imatinib to be 66.7 months (95%CI 61.7- infinity) compared to 7.7 (95%CI 6.0-12.6) in the historical group. Median-PFS were 45.3 months (95%CI 24.4-infinity) and 5.6 (95%CI 3.5-8.5) respectively. Imatinib effectiveness was similar to literature reports. The annual incremental CE ratio for imatinib was $15,882 CDN per median life year gained and $23,603 CDN per median year of PFS.


CONCLUSIONS
Imatinib for advanced GIST seems cost-effective in BC.


RESULTS
were robust across a range of sensitivity analyses.
Mabasa
Vincent H
VH
Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, B.C., Canada.
Taylor
Suzanne Cm
SC
Chu
Christina Cy
CC
Moravan
Veronika
V
Johnston
Karissa
K
Peacock
Stuart
S
Knowling
Meg
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000191:economics* / Q000627:therapeutic use*; D001549:Benzamides; D001955:British Columbia; D003362:Cost-Benefit Analysis; D018572:Disease-Free Survival; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000188:drug therapy* / Q000191:economics*; D006801:Humans; D000068877:Imatinib Mesylate; D008017:Life Expectancy; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000009:adverse effects / Q000191:economics* / Q000627:therapeutic use*; D011743:Pyrimidines / Q000009:adverse effects / Q000191:economics* / Q000627:therapeutic use*; D012189:Retrospective Studies
D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate