Cost-effectiveness analysis of trastuzumab in the adjuvant setting for treatment of HER2-positive breast cancer.
BACKGROUND
Adding trastuzumab to adjuvant chemotherapy provides significant clinical benefit in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer. A cost-effectiveness analysis was performed to assess clinical and economic implications of adding trastuzumab to adjuvant chemotherapy, based upon joint analysis of NSABP B-31 and NCCTG N9831 trials.


METHODS
A Markov model with 4 health states was used to estimate the cost utility for a 50-year-old woman on the basis of trial results through 4 years and estimates of long-term recurrence and death based on a meta-analysis of trials. From 6 years onward, rates of recurrence and death were assumed to be the same in both trastuzumab and chemotherapy-only arms. Incremental costs were estimated for diagnostic and treatment-related costs. Analyses were from payer and societal perspectives, and these analyses were projected to lifetime and 20-year horizons.


RESULTS
Over a lifetime, the projected cost of trastuzumab per quality-adjusted life year (QALY; discount rate 3%) gained was 26,417 dollars (range 9,104 dollars-69,340 dollars under multiway sensitivity analysis). Discounted incremental lifetime cost was 44,923 dollars, and projected life expectancy was 3 years longer for patients who received trastuzumab (19.4 years vs 16.4 years). During a 20-year horizon, the projected cost of adding trastuzumab to chemotherapy was 34,201 dollars per QALY gained. Key cost-effectiveness drivers were discount rate, trastuzumab price, and probability of metastasis. The cost-effectiveness result was robust to sensitivity analysis.


CONCLUSIONS
Trastuzumab for adjuvant treatment of early stage breast cancer was projected to be cost effective over a lifetime horizon, achieving a cost-effectiveness ratio below that of many widely accepted oncology treatments.
Garrison
Louis P
LP
Department of Pharmacy, University of Washington, Seattle, Washington, USA. lgarrisn@u.washington.edu
Lubeck
Deborah
D
Lalla
Deepa
D
Paton
Virginia
V
Dueck
Amylou
A
Perez
Edith A
EA
D000328:Adult; D000911:Antibodies, Monoclonal / Q000191:economics* / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000191:economics* / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy / Q000191:economics* / Q000378:metabolism; D017024:Chemotherapy, Adjuvant; D003362:Cost-Benefit Analysis; D018572:Disease-Free Survival; D004305:Dose-Response Relationship, Drug; D016527:Drug Costs; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008390:Markov Chains; D008875:Middle Aged; D009367:Neoplasm Staging; D019057:Quality-Adjusted Life Years; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D015996:Survival Rate; D000068878:Trastuzumab; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab