Use of ALK-tyrosine kinase inhibitors (ALK TKI) in clinical practice, overall survival, and treatment duration - a Swedish nationwide retrospective study

Background The real-world treatment and outcomes of patients with anaplastic lymphoma kinase positive (ALK+) advanced non-small cell lung cancer treated with ALK Tyrosine Kinase Inhibitor (TKI) drugs in Sweden is not well described. Material and methods A retrospective population-based cohort study was conducted using Swedish national registers. All patients with a filled prescription for an ALK TKI between January 2012 and October 2020 were included. The sequencing of ALK TKI and duration of treatment (DOT) were described, and overall survival (OS) was estimated using the Kaplan-Meier method. Patients were stratified based on treatment with frontline chemotherapy, presence of CNS metastases prior to the first ALK TKI, and generation of ALK TKI agent. Results Among the total of 579 patients, 549 (95%) underwent a therapy sequence in line with current clinical practice with 204 (37%) patients receiving frontline chemotherapy. Single-line ALK TKI was given to 366 patients (crizotinib: 211; alectinib: 146; ceritinib: 9), whereas 128 patients received two different ALK TKI (frontline crizotinib: 100, alectinib: 24, ceritinib: 4); 40 patients received three lines and 15 patients four ALK TKI lines or more. With frontline chemotherapy, the mean (standard deviation) DOT was 1.07 (1.25) years for the entire TKI therapy sequence compared to 1.23 (1.28) years with frontline ALK TKI. The median (95% confidence interval) OS was 1.83 (1.48-2.13) years for the entire cohort, 1.44 (0.89-1.98) years for patients given frontline chemotherapy, and 2.02 (1.60-2.58) years for patients given frontline ALK TKI. Conclusion This study provides a unique overview of the patient population treated with ALK TKI in Sweden and reveals the treatment patterns applied in real clinical practice. More research is needed when longer follow-up data are available for later-generation ALK TKI, to fully understand ALK TKI sequencing and its effect on patient survival in a real-world setting.Funding Agencies|Pfizer