OBJECTIVES: This study examined the recent trend in use and costs of antineoplastic agents for treatment of eye malignancies in Taiwan from 2009 to 2012. We also forecasted use and costs of targeted therapies up to and including year 2016 based on the current patterns. DESIGN: Retrospective observational study focusing on the usage of targeted therapies for treatment of eye malignancy. SETTING: The monthly claims data for eye malignancy-related antineoplastic agents were retrieved from Taiwan's National Health Insurance Research Database (2009-2012). MAIN OUTCOME MEASURES: We calculated the number of prescriptions and costs for each class of medications, and analysed their time trends. In addition, using a time series design with ARIMA models, we estimated the market share by prescription volume and the proportion of costs for targeted therapies for year 2016. RESULTS: The market share by prescription volume of targeted therapies grew from 1.56% in 2009 to 9.98% in 2012 among all antineoplastic agents, and the proportion of costs for targeted therapies rose from 15.12% in 2009 to 58.88% in 2012. Especially, the proportion of costs for protein kinase inhibitors grew from 25.62% to 45.28% among all antineoplastic agents between 2010 and 2012. The market share by prescription volume and the proportion of costs for targeted therapies for treatment of eye malignancies were predicted to reach 27.33% and 91.39% by the fourth quarter in 2016, respectively. CONCLUSIONS: This is the first study that examined and forecasted use and costs of targeted therapies for treatment of eye malignancies in Taiwan. Our findings indicate that, compared with other classes of drugs, targeted therapies are having a more and more relevant share among all treatment strategies for eye malignancies in Taiwan, and due to their high costs they are likely to cause great economic burden.