Monitoring for and Characterizing Crizotinib Progression: A Chart Review of ALK-Positive Non-Small Cell Lung Cancer Patients

Introduction: Crizotinib is recommended as first-line therapy for ALK-positive non-small cell lung cancer (NSCLC), but within a year of treatment initiation many patients develop resistance. With the recent approval of second-generation ALK inhibitors, this study assessed how physicians monitor for and diagnose progression and how they alter treatment following progression on crizotinib.

Methods: A panel of oncologists from the United States were surveyed regarding their monitoring practices and criteria for diagnosing progression on crizotinib. The physicians also retrospectively provided data (March-June 2016) from the medical charts of their adult patients with locally advanced or metastatic ALK-positive NSCLC who progressed on crizotinib after the approval (April 2014) of the first second-generation ALK inhibitor, ceritinib.

Results: A total of 28 physicians responded to the survey. Data was abstracted on 74 patients. In the physician survey, most physicians (71%) reported monitoring for radiographic progression every 3-4 months. When new lesions were detected, physician response varied. Following a symptomatic isolated lesion, most physicians (75%) would add local therapy and resume crizotinib. Following multiple symptomatic lesions, 96% and 64% of physicians would switch to a new therapy depending on whether the lesions were extracranial or isolated to the brain, respectively. For the patient cohort, physician-defined progression on crizotinib was diagnosed after a median of 10 months, and within 30 days of diagnosis, 86% of patients discontinued crizotinib. Among all patients who discontinued crizotinib, 77% switched to ceritinib, 14% to chemotherapy, and 1% to alectinib. The remaining 7% did not receive additional systemic antineoplastic therapy.

Conclusion: The findings from this physician survey and retrospective chart review study suggest that physician response to the development of new lesions in crizotinib-treated ALK-positive NSCLC patients varies with location and extent of the lesions. Once patients were considered to have progressed, most of them were immediately switched to ceritinib.

Funding: Novartis Pharmaceuticals Corporation.