Background: New drugs including cancer drugs and orphan drugs are becoming increasingly more expensive. Risk sharing arrangements (RSAs) could manage the risk based on both financial impact and the health outcome of new drugs if reimbursed. To improve patients’ access to new drugs under uncertainties, many developed countries have adopted RSAs. In this study, we aimed to understand the effects of RSAs in South Korea on patients’ access.Methods: We reviewed current status of RSA drugs in South Korea. The number of appraisals and time gap between market approval and reimbursement per RSA drug were considered to quantify improvement of patients’ access as they showed how rapidly decisions on reimbursement of RSA drugs were derived. Then, we applied a comparative analysis to determine whether the RSA drugs in South Korea were reimbursed in the UK, Italy, and Australia. Most data for this study were obtained from websites of the governmental department/agencies responsible for appraisal of drug reimbursement in each country. And literatures related to RSAs were investigated as well.Results: The eligibility for Korean RSAs had two key components - drugs for cancer and rare diseases and not having other alternative treatments. As of the first half of 2019, there were 39 RSA drugs reimbursed in South Korea, the majority of which were financial-based schemes. Refund and expenditure cap were the representative types (89.7%). After introduction of RSAs, the time gap and number of appraisals were decreased. Based on the indications of RSA drugs, the level of drug coverage in South Korea was found lower than Italy, similar to the UK, and higher than Australia.Conclusions: RSAs in South Korea significantly enhanced patients’ access to new drugs and led to the alleviation of patients’ out-of-pocket expenses. The drug coverage of South Korea had a level comparable to that of other countries. This study provides implications for countries that have a dual mission of containing pharmaceutical expenditure and improving access to new drugs.