Evaluating transportability of overall survival estimates from US to UK populations receiving first-line treatment for advanced non-small cell lung cancer: a retrospective cohort study.

OBJECTIVES

The objective of this study is to explore how the UK versus the USA compare in patient characteristics, treatment patterns and overall survival (OS) of patients with advanced non-small cell lung cancer (aNSCLC) initiating first-line (1L) treatment.

DESIGN

Retrospective cohort study.

SETTING

Oncology treatment centres in the USA and UK.

PARTICIPANTS

People in the USA and UK diagnosed with aNSCLC and treated in the 1L setting between 2016 and 2018. The US cohort was obtained from a nationwide electronic health record-derived deidentified database. The UK cohort information was derived from a published study exploring the patient characteristics, treatments and outcomes of people with aNSCLC in the UK.

INTERVENTIONS

1L chemotherapy, immunotherapy monotherapy or targeted therapy.

PRIMARY OUTCOME MEASURE

The primary outcome was OS-defined as the time from treatment initiation to death from any cause.

RESULTS

There were 1003 patients in the UK and 3819 in the US cohorts receiving 1L therapy for aNSCLC. After standardising the US cohort to the UK cohort, median OS in the USA and UK was similar across 1L drug classes: chemotherapies (7.7 (95% CI 7.1 to 8.3) vs 8.1 (95% CI 7.4 to 8.9) months), immunotherapies (13.9 (95% CI 11.0 to 17.1) vs 14.0 (95% CI 10.7 to 20.6)) and targeted therapies (21.6 (95% CI 18.5 to 23.7) vs 20.2 (95% CI 16.0 to 30.5)). OS curves for 1L immunotherapy and targeted therapy were almost overlapping after standardisation. OS after around 12 months was higher in US patients compared with UK patients receiving 1L chemotherapy regimens. Of those receiving 1L chemotherapy, the proportion receiving any second-line therapy appeared higher for patients in the USA versus UK.

CONCLUSIONS

The results suggest that in aNSCLC patients receiving 1L treatment, US data have the potential to be used in technology evaluations to understand long-term OS where UK data are unavailable or sparse.