Abstract Oncogenic rearrangements of the anaplastic lymphoma receptor tyrosine kinase (ALK gene) have recently been described in 3% to 5% of lung adenocarcinomas. Kinds of fusion partners of ALK have been reported in non-small-cell lung cancer (NSCLC), with echinoderm microtubule-associated protein-like 4 (EML4)-ALKbeing the most prevalent one. Several tyrosine kinase inhibitors have been approved for treating patients with advanced-stage ALK-positive, NSCLC by Food and Drugs Administration (FDA). Comprehensive genomic profiling performed by means of next-generation sequencing assay demonstrated a novel myosin phosphatase-Rho-interacting protein gene (MPRIP)-ALK fusion in our case, in which a translocation involving chromosomes 2 and 9 has taken place. The rearrangement was verified by reverse transcription reverse transcription polymerase chain reaction (RT-PCR) and Sanger sequencing. ALK immunohistochemistry demonstrated strong staining in patient’s tumor sample as extracted from formalin-fixed paraffin-embedded (FFPE) sections. We expressed MPRIP-ALK cDNA construct in non-cancer cell line Ba/F3 which showed IL-3-independent growth compared the growth stop of cells carrying empty vector, moreover, hyper-activation of the protein ALK, ERK, AKT were detected in Ba/F3 cells with MPRIP-ALK over-expressed. Furthermore, the colonies and activations of ALK downstream signaling pathways could be inhibited by crizotinib. The patient received standard chemotherapy on the first-line. She experienced progressive disease after 7 months, and commenced on crizotinib (250mg, twice per day) from March 2018. The patient showed significant improvement in cough, dorsalgia, and polypnea within one week. Partial response was gained after one month treatment and confirmed at the third month. She still remains on the crizotinib treatment without disease relapse up to now. In this study, we report a novel ALK rearrangement in a patient with NSCLC by RNA-seq. Our in vivo and in vitro studies have shown that the novel MPRIP-ALK fusion is a driver gene and can be targetable by crizotinib. Citation Format: Wenfeng Fang, Jiadi Gan, Feng Lu, Yangyang Deng, Liang Chen, Yunpeng Yang, Li Zhang. MPRIP-ALK,a novel ALK rearrangement that responds to ALK inhibitor in non-small-cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3460.