Assessing the real-world cost-effectiveness of adjuvant trastuzumab in HER-2/neu positive breast cancer.
BACKGROUND
Among women with surgically removed, high-risk HER-2/neu-positive breast cancer, trastuzumab has demonstrated significant improvements in disease-free and overall survival. The objective of this study is to evaluate the cost-effectiveness of the currently recommended 12-month adjuvant protocol of trastuzumab using a Markov modeling approach and real-world cost data.


METHODS
A 10-health-state Markov model tracked patients' quarterly transitions between health states in the local and advanced states of breast cancer. Clinical data were obtained from the joint analysis of the National Surgical Adjuvant Breast and Bowel Project and North Central Cancer Treatment Group, as well as from the metastatic study conducted by Norum et al. Clinical outcomes were adjusted for quality of life using utility estimates published in a systematic review. Real cost data were obtained from the British Columbia Cancer Agency and were evaluated from a payer perspective. Costs and utilities were discounted at 5% per year, respectively, for a 28-year time horizon.


RESULTS
In the base case analysis, treatment with a 12-month adjuvant trastuzumab regimen resulted in a gain of 1.38 quality-adjusted life years or 1.17 life years gained at a cost of $18,133 per patient. Thus, the cost per QALY gained for the base case is $13,095. Cost per LYG is $15,492.


CONCLUSIONS
Over the long term, treatment of HER-2/neu mutation positive breast cancer with a 12-month protocol of trastuzumab in the adjuvant setting is predicted to be cost-effective in a Canadian context.
Canadian Centre for Applied Research in Cancer Control, Vancouver, BC, V5Z 1L3 Canada.
Lindsay
L
Hedden
Susan
S
O'Reilly
Caroline
C
Lohrisch
Stephen
S
Chia
Caroline
C
Speers
Laurel
L
Kovacic
Suzanne
S
Taylor
Stuart
S
Peacock
D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000401:mortality; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D008390:Markov Chains; D009010:Monte Carlo Method; D019057:Quality-Adjusted Life Years; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D000068878:Trastuzumab
D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C508053:ERBB2 protein, human