OBJECTIVES:  Adverse Events (AEs) associated with existing and future treatments in Non-Small Cell Lung Cancer (NSCLC) are frequent, and may impact should be accounted for in health economic models. In addition to utility decrements, appropriate costing of AE management is needed. In the case of NSCLC which affects 45 200 patients in France, published data are scarce and not always complete. It was therefore thought of importance to assess resource use and costs associated with AEs. METHODS:  When looking at the grade 3 and4 AEs appearing for at least 1% of patients in the clinical trials for erlotinib (TITAN, LUX-LUNG 8), ramucirumab plus docetaxel (REVEL), docetaxel and pembrolizumab (KEYNOTE 010) a list of 20 grade 3 and 4 AEs was identified as relevant for Health Economic analysis. Among them, 7 did not had cost data available in the literature. Three French oncology experts were consulted. A questionnaire was sent before the meeting with the experts, asking for, according to the grade, insight on resource use (hospitalisation, follow-up visits, diagnosis exams, treatments). Results were discussed during the meeting in order to reach a consensus. Total cost per AE, expressed in 2016 Euros, was then calculated from a national health insurance perspective based on public and private weighted tariffs and 2014 PMSI database. RESULTS: The mean AE cost was €206 for thrombocytopenia, €263 for ocular toxic effect, €2,332 for arthralgia, €3,282 for venous thromboembolism, €3,732 for pulmonary bleeding, €5,176 for dehydration, €5,751 for pneumonia, infiltration or pneumonitis. Hospitalization costs corresponded to 46% to 100% of total AE cost. These AE costs were in line with the costs of other grade ¾ AEs previously published for NSCLC therapies. CONCLUSIONS: Among the seven AEs, four appear to have an important economic impact, with a management cost of at least €3,000.