Long-term survival estimates for imatinib versus interferon-alpha plus low-dose cytarabine for patients with newly diagnosed chronic-phase chronic myeloid leukemia.
BACKGROUND
The authors estimated survival among patients with chronic myeloid leukemia for a cost-effectiveness analysis of imatinib versus interferon-alpha plus low-dose cytarabine (IFN+LDAC).


METHODS
Two-year survival and cytogenetic response were determined using data from 553 patients who received first-line imatinib in the International Randomized Interferon versus ST571 Study (IRIS). Long-term survival was modeled on complete cytogenetic response (CCyR) after 2 years. Long-term survival for patients with a CCyR was modeled using data from a cohort study of 317 patients with CCyRs. Long-term survival for patients without a CCyR was modeled using data from a trial of 275 patients who were treated with IFN+LDAC. Computation of lifetime survival estimates for imatinib assumed a proportional hazards relation between survival for an age-matched and gender-matched cohort and survival for patients with and without a CCyR.


RESULTS
For IRIS patients receiving imatinib, the estimated survival was 95.8% and the CCyR rate was 73.8%. The average residual life expectancy was estimated to be 16.71 years for CCyR patients and 5.78 years for non-CCyR patients. The estimated life expectancy after treatment with imatinib was 15.30 years, compared with 9.07 years for patients who were treated with IFN+LDAC in previous studies.


CONCLUSIONS
Assuming the relation between CCyR and survival with interferon-alpha holds for imatinib, higher CCyR rates with imatinib therapy will result in an estimated 6.23 life-years gained compared with treatment with IFN+LDAC.
Anstrom
Kevin J
KJ
Center for Clinical and Genetic Economics, Duke Clinical Research Institute, Duke University Medical Center, Durham, North Carolina, USA.
Reed
Shelby D
SD
Allen
Andrew S
AS
Glendenning
G Alastair
GA
Schulman
Kevin A
KA
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001549:Benzamides; D015331:Cohort Studies; D003561:Cytarabine / Q000008:administration & dosage; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D016898:Interferon-alpha / Q000008:administration & dosage; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use*; D011379:Prognosis; D011743:Pyrimidines / Q000627:therapeutic use*; D016019:Survival Analysis; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D001549:Benzamides; D016898:Interferon-alpha; D010879:Piperazines; D011743:Pyrimidines; D003561:Cytarabine; D000068877:Imatinib Mesylate