Cost-Effectiveness of Liposomal vs Conventional Cytarabine-Daunorubicin for AML

In a study comparing the cost-effectiveness of liposomal cytarabine-daunorubicin (CPX-351) with conventional cytarabine-daunorubicin in the treatment of acute myeloid leukemia (AML), Jan Bewersdorf, MD, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, and colleagues found that CPX-351 may not be cost-effective under the current pricing.

In this video, Dr Bewersdorf discusses these findings, which were presented at the 2021 ASH Annual Meeting.

Transcript:

Hello. My name is Jan Philipp Bewersdorf, and I'm a fellow in medical oncology and hematology at Memorial Sloan Kettering Cancer Center in New York. I'm very grateful for the opportunity to discuss our study on the cost-effectiveness of liposomal cytarabine and daunorubicin, also known as CPX-351, compared to conventional cytarabine/daunorubicin in the treatment of acute myeloid leukemia, or AML. This work has been recently presented as an oral presentation at the 2021 ASH Annual Meeting.

By means of background, in light of increasing healthcare expenses in general and in oncology in particular, there has been increasing interest in the health economic implications of recent drug approvals, both in the United States and globally.

In this particular study, we analyze the cost-effectiveness of a liposomal formulation of cytarabine and daunorubicin, also known as CPX-351, compared to conventional cytarabine and daunorubicin in the treatment of older patients with newly diagnosed secondary AML.

CPX-351 has been approved in the United States by the FDA for the treatment of all adult patients with newly diagnosed secondary AML based on a phase III trial that showed an overall survival benefit of this novel formulation compared to standard 7+3. However, this randomized trial only enrolled patients between 60 and 75 years of age.

We used this randomized trial to conduct a partitioned survival analysis model. Model inputs, such as patient and disease characteristics, costs, utilities, and treatment patterns, were derived from the original trial or previously published literature estimates.

Given the overall older patient population in the trial, as well as in our model, we adopted a Medicare perspective for our cost estimates and used a 10 year time horizon to account for a limited life expectancy of older patients with secondary AML.

In our model, we found that CPX-351 and 7+3 were associated with lifetime costs of about $415,000 and $256,000, respectively, resulting in an incremental cost of $157,000 with CPX-351 over a 10 year time horizon.Based on an incremental gain of 0.49 quality adjusted life years with CPX-351, the incremental cost effectiveness ratio, or ICER, of the base case scenario was about $320,000/QALY, suggesting that CPX-351 is not cost-effective in this model.

We next conducted several sensitivity analyses and found that our model was most sensitive to the proportion of patients proceeding to allogeneic hematopoietic cell transplant.

However, none of the variables included in our model was able to lower the ICER below the conventional willingness to pay threshold of $150,000/QALY. Only a reduction in the average sales price of CPX-351 by about 80% would yield a reduction in the ICER to below the willingness to pay threshold of $150,000/QALY.

Finally, we conducted various probabilistic sensitivity analyses and found that 7+3 was favored in 99.98% of 10,000 iterations against the willingness to pay threshold of $150,000/QALY.

Therefore, we conclude that CPX-351 is unlikely to be cost-effective under the current pricing model in a similar population of older patients with secondary AML, and only a substantial reduction in the average sales price is able to make it cost-effective.

Studies such as ours are important to highlight the health economic implications of novel drugs and lend support to ongoing efforts aiming to curb drug prices. However, it's important to note that our findings only apply to a patient population similar to those included in the randomized phase III trials as well as in our model.

Thank you very much for your attention.