Therapeutic Potential of Afatinib in NRG1 Fusion-Driven Solid Tumors: A Case Series.

NRG1 fusions activate ErbB signaling and have been identified as oncogenic drivers in multiple solid tumor types. Afatinib is a pan-ErbB family inhibitor authorized for the treatment of advanced non-small cell lung cancer that may be effective in NRG1 fusion-driven tumors. This report summarizes six previously unpublished cases of NRG1 fusion-driven cancers treated with afatinib, including five with metastatic lung cancer and one with metastatic colorectal cancer. Several patients showed a prolonged response of >18 months with afatinib treatment. This case series adds to the evidence suggesting a potential role for afatinib in this area of unmet medical need.