OBJECTIVES: To investigate the characteristics of clinical trials conducted in 5 Asian countries over the past 2 years with a focus on: disease conditions, funding sources and age groups.  METHODS: ClinicalTrials.gov was searched for trials initiated after January 1, 2010 in the following countries: Indonesia, Korea, Malaysia, Taiwan and Thailand. The 10 most common conditions and trial sponsors were ranked and the percentage of trials in adults and children was calculated. These figures were compared between countries. RESULTS: During the time period, the following number of trials were identified (number; trials per 1,000,000 population): Taiwan (826; 35.6), Korea (1597; 32.7), Thailand (375; 5.4), Malaysia (132; 4.6) and Indonesia (47; 0.2). The most common trials in all countries were for chronic conditions. Trials on type 2 diabetes were the most common trials in Taiwan, Thailand, Malaysia and Indonesia (range: 3-18%), and were the 3rdmost common in Korea (2%). Breast cancer trials were also common in all 5 countries (range: 1-2%) and non-small cell lung cancer trials were common in 4 countries (range: 1-2%), except Indonesia. Funding for the trials was predominantly non-industry in Taiwan, Thailand and Korea (64%, 61% and 53% respectively), but predominantly industry in Malaysia and Indonesia (72% and 54% respectively). Over 40% of trials in Taiwan were sponsored by local medical institutions. Trials in adults alone were the most common in all countries: Korea (84%), Malaysia (84%), Taiwan (81%), Thailand (74%) and Indonesia (65%).  CONCLUSIONS: The number of trials per 1,000,000 population was much higher in Taiwan and Korea than in Thailand, Malaysia and Indonesia. Trials conducted in all these countries, however, show strong similarities in terms of the conditions studied; although there are some differences (e.g. funding sources) between the countries that suggest other factors influence clinical trials in these countries.