Cost-effectiveness of axicabtagene ciloleucel versus lisocabtagene maraleucel for adult patients with relapsed or refractory large B-cell lymphoma after two or more lines of systemic therapy in the US

AIMS

This study evaluated from a US payer perspective the cost-effectiveness of two chimeric antigen receptor T (CAR T) cell therapies, axicabtagene ciloleucel (axi-cel) versus lisocabtagene maraleucel (liso-cel), for the treatment of adult patients with relapsed or refractory (r/r) large B-cell lymphoma (LBCL) following two or more systemic therapy lines.

METHODS

We developed a 3-state (i.e., pre-progression, post-progression, death) partitioned survival model to estimate patients' lifetime outcomes. Mixture cure models were used for survival extrapolation to account for long-term remission. Survival inputs were based on a matching-adjusted indirect comparison (MAIC) that reweighted the ZUMA-1 population (receiving axi-cel) to match patient characteristics in TRANSCEND-NHL-001 (assessing liso-cel). Costs included apheresis, drug acquisition, and administration for conditioning chemotherapy and CAR T therapies, monitoring, transplant, hospitalization, adverse events, routine care, and terminal care, per published literature and databases. Utilities were derived from ZUMA-1 and literature. Deterministic and probabilistic sensitivity analyses were conducted.

RESULTS

In the base case, axi-cel was associated with more QALYs (7.76 vs. 5.94) and greater costs overall ($611,440 vs. $597,174) than liso-cel, at $7,843/QALY gained. The incremental costs (+$14,266) were largely driven by higher routine care costs (+$18,596) due to longer survival and hospitalization (+$10,993) but partially offset by reduced costs of CAR T acquisition (‒$11,300) and terminal care (‒$4,025). Sensitivity analyses consistently suggested robustness of base-case results.

LIMITATIONS

This study relied on an MAIC in which trial design differences and unobserved confounders could not be accounted for. Future real-world studies for recently approved CAR T are warranted to validate our results. Due to a lack of data, we assumed equivalent use of transplants and treatment for B-cell aplasia between the two therapies based on clinicians' opinions.

CONCLUSIONS

In the US, axi-cel is a potentially cost-effective treatment option compared with liso-cel for adult patients with r/r LBCL after two or more systemic therapy lines.

Using the 'new' statistics in nursing research

This paper argues that quantitative methods are under-used in nursing research. Although this is often because the qualitative approach is the most appropriate, it may also be because nurse researchers are not fully aware of modern, sophisticated data analysis techniques and have tended to use simple statistical techniques that often make the quantitative analysis of complex data very difficult and produce simplistic and unsatisfactory answers. The paper briefly discusses probability and survival modelling techniques suitable for use in complex nursing research situations and argues that these methods may help to bridge the qualitative-quantitative gap. Although these techniques are mathematically complex, they are easily applied in practice using dedicated computer programs. The paper describes their application using one such program, GLIM 4.

Evidence for curvilinearity in the cancer incidence dose-response in the Japanese atomic bomb survivors

The recently released data on cancer incidence in the Japanese atomic bomb survivors are analysed using a variety of relative risk models which take account of errors in estimates of dose to assess the dose-response at low doses. For all solid cancers analysed together there is a significant positive dose-response (at the one-sided 2.5% significance level) if all survivors who received < 0.5 Sv are considered, but the significance vanishes if doses of < 0.2 Sv are considered. If a relative risk model with a threshold (the dose-response being assumed linear above the threshold) is fitted to the solid cancer data, a threshold of more than about 0.2 Sv is inconsistent with the data, whereas these data are consistent with there being no threshold. Linear-quadratic models and linear-quadratic models with an exponential cell-sterilization term provide no better fit than the linear model. For the three main radiation-inducible leukaemia subtypes analysed together (acute lymphatic leukaemia, acute myeloid leukaemia and chronic myeloid leukaemia) there is a significant positive dose-response (at the one-sided 2.5% significance level) if all survivors who received < 0.5 Sv are considered, but the significance vanishes if doses of < 0.2 Sv are considered. If a relative risk model with a threshold (the dose-response being assumed linear above the threshold) is fitted to the leukaemia data, a thresh-old of more than about 0.3 Sv is inconsistent with the data. In contrast with the solid cancer data, the best estimate for the threshold level in the leukaemia data is significantly different from zero, even when allowance is made for a possible quadratic term in the dose-response, albeit at borderline levels of statistical significance (p = 0.04). There is little evidence for curvature in the leukaemia dose-response from 0.2 Sv upwards. However, the possible underestimation of the errors in the estimates of the dose threshold as a result of confounding and uncertainties not taken into account in the analysis, together with the lack of biological plausibility of a threshold, makes the interpretation of this finding questionable.