Cost-Effectiveness of BTKis in Medicare Patients With CLL in First-Line and Relapsed/Refractory Settings
Introduction
Ibrutinib, acalabrutinib, and zanubrutinib are bruton tyrosine Kinase tnhibitors (BTKis) approved for the treatment of chronic lymphocytic leukemia (CLL). This study presents an updated cost-effectiveness analysis of ibrutinib compared with acalabrutinib and zanubrutinib under the new Centers for Medicare & Medicaid Services–negotiated maximum fair price (MFP).
Methods
A semi-Markov simulation model estimated clinical outcomes, adverse events, and costs of ibrutinib at the MFP compared with acalabrutinib and zanubrutinib at their current wholesale acquisition costs (WACs) in both first-line (1L) and relapsed/refractory (R/R) CLL. The model incorporated treatment-related care during both progression-free and post-progression periods, as well as subsequent treatment, progression-free survival, overall survival, and safety and tolerability data from a US Medicare perspective. Clinical outcomes were measured in terms of quality-adjusted life years (QALYs) and equal-value life years gained (evLYG). Costs were reported as per patient per month (PPPM) over a 1-year time horizon (TH). Incremental cost-effectiveness ratios (ICER)s and evLYG were calculated for ibrutinib compared with acalabrutinib and zanubrutinib. Scenario analyses incorporating match-adjusted indirect comparisons and head-to-head clinical trials were conducted to test the robustness of key findings. One-way and probabilistic sensitivity analyses were also performed.
Results
In the base case analysis, evLYGs over a 1-year TH were 0.78 for ibrutinib and 0.77 for both acalabrutinib and zanubrutinib in 1L CLL. For R/R CLL, evLYGs were 0.75, 0.75, and 0.76, respectively. Total costs over 1 year in 1L CLL and R/R CLL were $122 757 and $124 652 for ibrutinib, $179 101 and $183 514 for acalabrutinib, and $179 161 and $178 679 for zanubrutinib. Incremental costs versus ibrutinib in 1L CLL and R/R CLL, respectively, were -$56 344 and -$58 862 for acalabrutinib and -$56 404 and -$54 027 for zanubrutinib. ICERs in 1L CLL for ibrutinib were dominant (less expensive with similar or better outcomes) compared with acalabrutinib and zanubrutinib. In R/R CLL, acalabrutinib and zanubrutinib at their current WACs were not cost-effective relative to ibrutinib MFP at a willingness-to-pay threshold of $150 000/QALY. PPPM costs for ibrutinib, acalabrutinib, and zanubrutinib were $10 431, $15 336, and $15 369 for 1L CLL and $11 017, $16 112, and $15 543 for R/R CLL, respectively. PPPY costs for ibrutinib, acalabrutinib, and zanubrutinib were $125 170, $184 030, and $184 427 for 1L CLL treatment and $132 205, $193 345, and $186 517 for R/R CLL treatment, respectively. To be cost-effective versus ibrutinib in 1L CLL over a 1-year TH, a discount of 33% relative to WAC would be required for either acalabrutinib or zanubrutinib. For R/R CLL, the required acalabrutinib and zanubrutinib discounts are 36% and 31%, respectively. Results were robust across scenario, one-way sensitivity, and probabilistic sensitivity analyses.
