Investigating the Cost-Effectiveness of Durvalumab

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When it comes to the treatment of unresectable locally advanced stage III non–small cell lung cancer (NSCLC), the standard of care process features definitive chemoradiotherapy, followed by maintenance immunotherapy with durvalumab. In these instances, the obstacle is durvalumab’s cost of use in health systems, along with access, health system approvals, and patient eligibility.

There are phase III trials that positively support its use—including five-year long-term outcomes that measured progression-free survival and overall survival—but these haven’t come to fruition.

Keeping this in mind, a study published in JAMA Network Open¹ sought to address one main question: From the viewpoint of numerous payers, is maintenance durvalumab therapy a cost-effective option for the treatment of unresectable stage III non–small cell lung cancer?

From June 1, 2022, through Dec. 27, 2023, investigators conducted a cost-effectiveness analysis according to four country perspectives from the United States, Brazil, Singapore, and Spain.

Using clinical data from the PACIFIC, ADAURA, ALEX, KEYNOTE-189, and REVEL randomized clinical trials (using five-year outcomes data) encompassing consolidative chemoradiotherapy, followed by one year of maintenance durvalumab immunotherapy, or only consolidative chemoradiotherapy, they designed a Markov decision-analytic model. In both arms, patients received standard-of-care therapy at the first (POD1), along with second (POD2) instances of disease progression as defined by EGFR, ALK, and PD-L1 tumor proportion score biomarker status on a 10-year perspective.

This model simulated 1,000 patients over 30-day spans, which after that time, patients would switch state-to-state; if a patient was progressing on PACIFIC’s durvalumab or placebo treatment arms, this would be the first instance of disease progression (POD1), so it would be followed by a transition to the treatment arm of either ALEX, FLAURA, or KEYNOTE-189.

That was where the analysis of the various countries came in. The investigators acquired country-specific costs on drug acquisition, diagnosis, supportive care, drug administration, monitoring, and end-of-life costs.

When it came to the US base-case model, treatment with durvalumab was associated with an increased cost of $114, 394 and improved effectiveness of 0.50 quality-adjusted life years (QALYs) compared with placebo, leading to an incremental cost-effectiveness ratio (ICER) of $228,788 per QALY.

Base-case models also noted that ICERs were $141 ,146, $153 ,461, and $125,193 for Brazil, Singapore, and Spain respectively. Also, durvalumab price adjustments to the PACIFIC data boosted cost-effectiveness in Singapore, with an ICER of $45,164. This model was most sensitive to the efficacy durvalumab.

Although the study presented its share of strengths—such as its use of several lines of therapy, timeframe, and a biomarker-guided treatment paradigm—there were various limitations to the analysis, with one primary restriction being that the study was tied to utilities estimates within the immunotherapy period; there was no sort of agreement pertaining to any updated functions that are able to suggest treatment using immune checkpoint inhibitors.

The investigators concluded that, “In this economic evaluation, durvalumab was not cost-effective in our model in any of the four countries studied despite being highly efficacious in the maintenance setting after consolidative chemoradiotherapy for unresectable stage III NSCLC. In Singapore, the institution of an industry-sponsored access program greatly decreased drug costs, thereby converting durvalumab into a cost-effective therapy.”

Reference

1. Kareff SA, Han S, Haaland B, et al. International Cost-Effectiveness Analysis of Durvalumab in Stage III Non–Small Cell Lung Cancer. JAMA Netw Open. 2024;7(5):e2413938. doi:10.1001/jamanetworkopen.2024.13938