This year, generic imatinib will be introduced in the United States and Europe and, according to a study published in the Journal of the National Cancer Institute, it will be the most cost-effective first-line tyrosine kinase inhibitor for chronic myeloid leukemia (CML). Researchers estimate that the per-person, per-month cost of imatinib will drop 60 to 90 percent due to the drug’s patent loss and the introduction of the generic form.
The study examined the five-year, cost-effectiveness of first-line imatinib versus physician’s choice from a U.S. commercial payer perspective. Their model assumed a 3 percent annual discounting (in 2013 U.S. dollars). The cost per quality-adjusted life-year (QALY; the study’s primary endpoint) was estimated based on per-person spending on chronic-phase CML from insurance claims data from 397 patients. The “willingness-to-pay” threshold was set at $100,000 per QALY.
The average per-person cost of treatment for branded imatinib was $79,000 per year, while other physician’s choice treatment options (dasatinib and nilotinib) ranged from $87,000 to $92,000 per year.
However, the mean annual cost of the drug itself was lower for imatinib than the other options: $59,000 for imatinib, $76,000 for dasatinib, and $75,000 for nilotinib. The authors added that, following the end of imatinib’s patent exclusivity, the total cost of imatinib-based treatment was expected to decrease to $46,000 per year.
Overall though, both treatment choices met the willingness-to-pay threshold compared with a no-alternative-treatment option.
The researchers noted some limitations of the study, including the fact that the model assumes perfect patient adherence and that data on additional TKI-switching among patients were lacking.
Source: Padula WV, Larson RA, Dusetzina SB, et al. Cost-effectiveness of tyrosine kinase inhibitor treatment strategies for chronic myeloid leukemia in chronic phase after generic entry of imatinib in the United States. J Natl Cancer Inst. 2016;108:djw003.