Lorlatinib induced proteinuria: A case report.

INTRODUCTION: Lorlatinib is an oral anaplastic lymphoma kinase (ALK) and C-ros oncogene (ROS1) tyrosine kinase inhibitor with excellent central nervous system (CNS) penetrability. It is currently approved for use as second line therapy for those with ALK positive non-small cell lung cancer (NSCLC). Given its CNS penetrating effects, lorlatinib has shown to cause CNS adverse events such as seizures, hallucinations, and changes in cognitive function. To our knowledge proteinuria has not been previously described with this medication. CASE REPORT: We report a case lorlatinib induced proteinuria in a patient receiving lorlatinib as second line treatment for ROS1 rearranged NSCLC.Management & Outcome: The patient's dose was reduced from 100 mg to 75 mg and further down to to 50 mg daily. At that point the proteinuria improved. Other adverse events attributable to the medication, specifically hallucinations and peripheral neuropathy also improved. DISCUSSION: Our case demonstrates objective evidence for proteinuria induced by lorlatinib, which may also be dose dependent.